Shai Friedland
Professor of Medicine (Gastroenterology and Hepatology)
Medicine - Gastroenterology & Hepatology
Clinical Focus
- Endoscopy
- Gastroenterology
Academic Appointments
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Professor - University Medical Line, Medicine - Gastroenterology & Hepatology
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Member, Wu Tsai Neurosciences Institute
Professional Education
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Fellowship: Stanford University Division of Gastroenterology and Hepatology (2002) CA
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Medical Education: University of California San Diego School of Medicine (1996) CA
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Residency: Stanford University Internal Medicine Residency (1999) CA
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Internship: Stanford University Internal Medicine Residency (1997) CA
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Board Certification: American Board of Internal Medicine, Gastroenterology (2002)
Current Research and Scholarly Interests
1. Gastrointestinal Endoscopy- Techniques and Outcomes
2. Noninvasive colorectal cancer screening
3. Medical device development in gastroenterology
Clinical Trials
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Fluorescent Probe VGT-309 to ID Cancerous Colorectal Lesions During Augmented Colonoscopy
Recruiting
The purpose of this study is to determine the safety and feasibility of VGT-309 for the visualization of colorectal tumors in real-time using near-infrared (NIR) fluorescence endoscopy. In addition, signatures of 50+ biomarkers will be evaluated in biopsies using CODEX multi-plexing.
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Advanced Gastrointestinal Endoscopic Imaging
Not Recruiting
To develop new methods to detect malignant and premalignant conditions of the gastrointestinal tract.
Stanford is currently not accepting patients for this trial. For more information, please contact Cancer Clinical Trials Office, MD, 650-498-7061.
2024-25 Courses
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Independent Studies (5)
- Directed Reading in Medicine
MED 299 (Aut, Win, Spr, Sum) - Early Clinical Experience in Medicine
MED 280 (Aut, Win, Spr, Sum) - Graduate Research
MED 399 (Aut, Win, Spr, Sum) - Medical Scholars Research
MED 370 (Aut, Win, Spr, Sum) - Undergraduate Research
MED 199 (Aut, Win, Spr, Sum)
- Directed Reading in Medicine
All Publications
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A prospective randomized controlled trial of water exchange plus cap versus water exchange colonoscopy in unsedated Veterans.
Gastrointestinal endoscopy
2024
Abstract
BACKGROUND AND AIMS: Water exchange (WE) and cap-assisted colonoscopy (CAC) separately reduced pain during insertion in unsedated patients. We hypothesized that compared with WE, WECAC could significantly lower real-time maximum insertion pain (RTMIP).METHODS: Veterans without escort were recruited, randomized, blinded, and examined at three United States Veterans Affairs sites. The primary outcome was RTMIP, highest segmental pain (0 = no pain, 10 = most severe pain) during insertion.RESULTS: Randomization [WECAC (n = 143) and WE (n = 137)] produced even distribution of a racially diverse group of males and females of low socioeconomic status. Intention-to-treat analysis reported results of WECAC (listed first) and WE (listed second): cecal intubation [93%, 94.2%]; mean (SD) of RTMIP [2.9 (2.5), 2.6 (2.4)]; the proportion with no pain (28.7%, 27.7%); the insertion time [18.6 (15.6), 18.8 (15.9) min]; overall ADR (55.2%, 62.8%), all P values were > 0.05. When RTMIP was binarized as "no pain" (0) vs. "some pain" (1-10), or "low pain" (0-7) vs. "high pain" (8-10), different significant predictors (see text) of RTMIP were identified.CONCLUSIONS: Unsedated colonoscopy was appropriate for unescorted Veterans. WE alone was sufficient. Adding a cap did not reduce RTMIP. Patient specific factors and application of WE with insertion suction of infused water contributed to high and low RTMIP, respectively. For unesorted patients, selecting those with low anxiety, avoiding low body mass index, history of depression or self-reported poor health and adhering to the steps of WE can minimize RTMIP to ensure success of unsedated colonoscopy.
View details for DOI 10.1016/j.gie.2024.07.010
View details for PubMedID 39053653
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EVALUATION OF THE SAFETY AND FEASIBILITY OF OUTPATIENT COLORECTAL ENDOSCOPIC SUBMUCOSAL DISSECTION
MOSBY-ELSEVIER. 2024: AB505-AB506
View details for Web of Science ID 001278323002056
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LONG TERM OUTCOMES OF NON-CURATIVE ENDOSCOPIC SUBMUCOSAL DISSECTION FOR COLORECTAL LESIONS
MOSBY-ELSEVIER. 2024: AB469-AB470
View details for Web of Science ID 001278323001422
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OUTCOMES OF ENDOSCOPIC SUBMUCOSAL DISSECTION FOR SUPERFICIAL ESOPHAGEAL SQUAMOUS NEOPLASMS: A MULTICENTER NORTH AMERICAN EXPERIENCE
MOSBY-ELSEVIER. 2024: AB992-AB993
View details for Web of Science ID 001278323004037
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NORTH AMERICAN EXPERIENCE OF ENDOSCOPIC SUBMUCOSAL DISSECTION OF DISTAL RECTAL LESIONS EXTENDING TO THE DENTATE LINE - A LARGE SCALE MULTICENTER STUDY
MOSBY-ELSEVIER. 2024: AB470-AB471
View details for Web of Science ID 001278323001423
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Real Time Maximum Insertion Pain in Unsedated Colonoscopy - Water Exchange vs Water Exchange Plus Cap: A Multi-Site, Multi-Investigator Randomized Controlled Trial in Veterans
LIPPINCOTT WILLIAMS & WILKINS. 2023: S541
View details for Web of Science ID 001091849301286
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Evaluation of Computer Aided Detection During Colonoscopy Among Veterans: A Randomized Clinical Trial
LIPPINCOTT WILLIAMS & WILKINS. 2023: S264
View details for Web of Science ID 001091849300360
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Artificial Intelligence-Assisted Colonoscopy in Real World Clinical Practice: A Systematic Review and Meta-Analysis
LIPPINCOTT WILLIAMS & WILKINS. 2023: S264-S265
View details for Web of Science ID 001091849300361
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Low Delayed Bleeding and High Complete Closure Rate of Mucosal Defects with the Novel Through-The-Scope Dual Action Tissue Clip After Endoscopic Resection of Large Non-Pedunculated Colorectal Lesions.
Gastrointestinal endoscopy
2023
Abstract
Complete closure following endoscopic resection (ER) of large non-pedunculated colorectal lesions (LNPCLs) can reduce delayed bleeding but is challenging with conventional through-the-scope (TTS) clips alone. The novel dual action tissue (DAT) has clip arms that open and close independent of each other, facilitating tissue approximation. We aimed to evaluate the rate of complete closure and delayed bleeding with the DAT clip after ER of LNPCLs.Multicenter prospective cohort study of all patients who underwent defect closure with the DAT clip following endoscopic mucosal resection (EMR) or submucosal dissection (ESD) of LNPCLs ≥ 20 mm from July 2022 to May 2023. Delayed bleeding was defined as bleeding event requiring hospitalization, blood transfusion or any intervention within 30 days after the procedure. Complete closure was defined as apposition of mucosal defect margins without visible submucosal areas < 3 mm along the closure line.A total of 107 patients (median age 64 years; 42.5% women) underwent EMR (n=63) or ESD (n=44) of LNPCLs (median size 40 mm; 74.8% right colon) followed by defect closure. Complete closure was achieved in 96.3% (n=103) with a mean of 1.4±0.6 DAT and 2.9±1.8 TTS clips. Delayed bleeding occurred in one patient (0.9%) without requiring additional interventions.The use of the DAT clip in conjunction with TTS clips achieved high complete defect closure after ER of large LNPCLs and was associated with a 0.9% delayed bleeding rate. Future comparative trials and formal cost-analyses are needed to validate these findings.
View details for DOI 10.1016/j.gie.2023.07.025
View details for PubMedID 37481003
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Strategies to manage the difficult colonoscopy.
World journal of gastrointestinal endoscopy
2023; 15 (7): 491-495
Abstract
During endoscopy, an endoscopist is inevitably faced with the occasional "difficult colonoscopy," in which the endoscopist finds it challenging to advance the endoscope to the cecum. Beyond optimization of technique, with minimized looping, minimal insufflation, sufficient sedation, and abdominal splinting when needed, sometimes additional tools may be needed. In this review, we cover available techniques and technologies to help navigate the difficult colonoscopy, including the ultrathin colonoscope, rigidizing overtube, balloon-assisted colonoscopy and the abdominal compression device.
View details for DOI 10.4253/wjge.v15.i7.491
View details for PubMedID 37547242
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Multicenter evaluation of recurrence in endoscopic submucosal dissection and endoscopic mucosal resection in the colon: A Western perspective.
World journal of gastrointestinal endoscopy
2023; 15 (6): 458-468
Abstract
BACKGROUND: While colon endoscopic mucosal resection (EMR) is an effective technique, removal of larger polyps often requires piecemeal resection, which can increase recurrence rates. Endoscopic submucosal dissection (ESD) in the colon offers the ability for en bloc resection and is well-described in Asia, but there are limited studies comparing ESD vs EMR in the West.AIM: To evaluate different techniques in endoscopic resection of large polyps in the colon and to identify factors for recurrence.METHODS: The study is a retrospective comparison of ESD, EMR and knife-assisted endoscopic resection performed at Stanford University Medical Center and Veterans Affairs Palo Alto Health Care System between 2016 and 2020. Knife-assisted endoscopic resection was defined as use of electrosurgical knife to facilitate snare resection, such as for circumferential incision. Patients ≥ 18 years of age undergoing colonoscopy with removal of polyp(s) ≥ 20 mm were included. The primary outcome was recurrence on follow-up.RESULTS: A total of 376 patients and 428 polyps were included. Mean polyp size was greatest in the ESD group (35.8 mm), followed by knife-assisted endoscopic resection (33.3 mm) and EMR (30.5 mm) (P < 0.001). ESD achieved highest en bloc resection (90.4%) followed by knife-assisted endoscopic resection (31.1%) and EMR (20.2%) (P < 0.001). A total of 287 polyps had follow-up (67.1%). On follow-up analysis, recurrence rate was lowest in knife-assisted endoscopic resection (0.0%) and ESD (1.3%) and highest in EMR (12.9%) (P = 0.0017). En bloc polyp resection had significantly lower rate of recurrence (1.9%) compared to non-en bloc (12.0%, P = 0.003). On multivariate analysis, ESD (in comparison to EMR) adjusted for polyp size was found to significantly reduce risk of recurrence [adjusted hazard ratio 0.06 (95%CI: 0.01-0.57, P = 0.014)].CONCLUSION: In our study, EMR had significantly higher recurrence compared to ESD and knife-assisted endoscopic resection. We found factors including resection by ESD, en bloc removal, and use of circumferential incision were associated with significantly decreased recurrence. While further studies are needed, we have demonstrated the efficacy of ESD in a Western population.
View details for DOI 10.4253/wjge.v15.i6.458
View details for PubMedID 37397977
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COMPARING THROUGH-THE-SCOPE HELIX TACK AND SUTURE DEVICE (TTSS) WITH THROUGH-THE-SCOPE CLIPS (TTSC) IN MUCOSAL DEFECT CLOSURE FOLLOWING COLORECTAL ENDOSCOPIC SUBMUCOSAL DISSECTION (ESD): A PROPENSITY SCORE-MATCHED ANALYSIS
MOSBY-ELSEVIER. 2023: AB736-AB737
View details for Web of Science ID 001038022801558
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INITIAL MULTICENTER PROSPECTIVE EXPERIENCE ON A NOVEL DUAL ACTION TISSUE CLIP FOR COMPLETE CLIP CLOSURE AFTER RESECTION OF LARGE NON-PEDUNCULATED COLORECTAL POLYPS (LNPCPS)
MOSBY-ELSEVIER. 2023: AB501-AB502
View details for Web of Science ID 001038022801181
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ENDOSCOPIC SUBMUCOSAL DISSECTION OF ESOPHAGEAL ADENOCARCINOMA DEEMED PATHOLOGICALLY CURATIVE RESULTS IN FEW RECURRENCES AT LONG-TERM SURVEILLANCE: A NORTH AMERICAN STUDY
MOSBY-ELSEVIER. 2023: AB1018-AB1019
View details for Web of Science ID 001038022802336
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Use of anchor pronged clips to close complex polyp resection defects.
VideoGIE : an official video journal of the American Society for Gastrointestinal Endoscopy
2023; 8 (6): 245-246
Abstract
Video 1Demonstration of anchored pronged clips to close complex polyp resection defects.
View details for DOI 10.1016/j.vgie.2023.02.002
View details for PubMedID 37303703
View details for PubMedCentralID PMC10251435
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OUTCOMES OF ENDOSCOPIC SUBMUCOSAL DISSECTION FOR PREVIOUSLY ATTEMPTED COLORECTAL LESIONS: AN INTERNATIONAL MULTICENTER EXPERIENCE
MOSBY-ELSEVIER. 2023: AB430-AB431
View details for Web of Science ID 001038022801059
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ENDOSCOPIC SUBMUCOSAL DISSECTION OF ESOPHAGEAL ADENOCARCINOMA DEEMED PATHOLOGICALLY CURATIVE RESULTS IN FEW RECURRENCES AT LONG-TERM SURVEILLANCE: A NORTH AMERICAN STUDY
MOSBY-ELSEVIER. 2023: AB1105-AB1106
View details for Web of Science ID 001038022802459
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INITIAL MULTICENTER PROSPECTIVE EXPERIENCE ON A NOVEL DUAL ACTION TISSUE CLIP FOR COMPLETE CLIP CLOSURE AFTER RESECTION OF LARGE NON-PEDUNCULATED COLORECTAL POLYPS (LNPCPS)
MOSBY-ELSEVIER. 2023: AB416-AB417
View details for Web of Science ID 001038022801034
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Evaluation of computer aided detection during colonoscopy in the community (AI-SEE): a multicenter randomized clinical trial.
The American journal of gastroenterology
2023
Abstract
There has been increasing interest in artificial intelligence in gastroenterology. To reduce miss rate during colonoscopy, there has been significant exploration in computer aided detection (CADe) devices. In this study, we evaluate the use of CADe in colonoscopy in community-based, non-academic practices.Between September 28, 2020 and September 24, 2021, a randomized controlled trial (AI-SEE) was performed evaluating the impact of CADe on polyp detection in 4 community-based endoscopy centers in the USA. Patients were block randomized to undergoing colonoscopy with or without CADe (EndoVigilant). Primary outcomes measured were adenomas per colonoscopy (APC) and adenomas per extraction (APE; the percentage of polyps removed that are adenomas). Secondary endpoints included serrated polyps per colonoscopy, non-adenomatous, non-serrated polyps per colonoscopy, adenoma and serrated polyp detection rate, and procedural time.A total of 769 patients were enrolled (387 with CADe), with similar patient demographics between the two groups. There was no significant difference in adenomas per colonoscopy in the CADe and non-CADe groups (0.73 vs 0.67, p=0.496). While use of CADe did not improve identification of serrated polyps per colonoscopy (0.08 vs 0.08, p=0.965), use of CADe increased identification of non-adenomatous, non-serrated polyps per colonoscopy (0.90 vs 0.51, p<0.0001), resulting in a lower APE in the CADe group. Adenoma detection rate (35.9 vs 37.2%, p=0.774) and serrated polyp detection rate (6.5 vs 6.3%, p=1.000) were similar in the CADe and non-CADe group. Mean withdrawal time was longer in the CADe compared to non-CADe group (11.7 vs 10.7 minutes, p=0.003). However, when no polyps were identified, there was similar mean withdrawal time (9.1 vs 8.8 minutes, p=0.288). There were no adverse events.Use of CADe did not result in a statistically significant difference in the number of adenomas detected. Additional studies are needed to better understand why some endoscopists derive substantial benefits from CADe and others do not. ClinicalTrials.gov number, NCT04555135.
View details for DOI 10.14309/ajg.0000000000002239
View details for PubMedID 36892545
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Clinical performance of a multimodal screening blood test for advanced adenomas and CRC in an average-risk cohort of 1,038 participants.
LIPPINCOTT WILLIAMS & WILKINS. 2023: 75
View details for Web of Science ID 001093994600181
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Factors Associated With Advanced Histological Diagnosis and Upstaging After Endoscopic Submucosal Dissection of Superficial Gastric Neoplasia
TECHNIQUES AND INNOVATIONS IN GASTROINTESTINAL ENDOSCOPY
2023; 25 (1): 2-10
View details for DOI 10.1016/j.tige.2022.07.002
View details for Web of Science ID 001054280600001
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A NOVEL THROUGH-THE-SCOPE HELIX TACK AND SUTURE DEVICE FOR MUCOSAL DEFECT CLOSURE FOLLOWING COLORECTAL ENDOSCOPIC SUBMUCOSAL DISSECTION (ESD): A MULTICENTER STUDY.
Endoscopy
2022
Abstract
Complete closure of large mucosal defects following colorectal ESD with through-the-scope clips (TTSC) is oftentimes not possible. We aimed to report an early experience of using a novel through-the-scope suturing system (TTSS) for closing large mucosal defects after colorectal ESD.We performed a retrospective, multi-center cohort study of consecutive patients who underwent attempted prophylactic defect closure using TTSS after colorectal ESD. The primary outcome was technical success in achieving complete defect closure, defined as (<5mm) residual mucosal defect in the closure line using TTSS with or without adjuvant TTSC.Eighty-two patients with a median defect size of 30 mm [25-40] were included. Technical Success was achieved in 92.7% (n=76) using TTSS only in 44(53.7%) and a combination of TTSS to approximate the widest segment followed by complete closure with TTSCs in 32(39%) patients. Incomplete/partial closure, failure of appropriate TTSS deployment, and need for over-the-scope salvage closure methods were observed in 7.3%(n=6). One intraprocedural bleed, 1 delayed bleed, and 3 intraprocedural perforations were observed. There were no adverse events related to the placement of TTSS.TTSS is an effective and safe tool for the closure of large mucosal defects after colorectal ESD and is an alternative when complete closure with TTSC alone is not possible.
View details for DOI 10.1055/a-1970-5528
View details for PubMedID 36323330
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Use of a novel dual-action clip for closure of complex endoscopic resection defects.
VideoGIE : an official video journal of the American Society for Gastrointestinal Endoscopy
2022; 7 (11): 389-391
Abstract
Video 1Use of dual-action clips and clips with added atraumatic teeth to close complex endoscopic resection defects.
View details for DOI 10.1016/j.vgie.2022.08.005
View details for PubMedID 36407049
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De Novo Diagnosis of Lymphocytic Colitis After SARS-CoV-2 Vaccination.
ACG case reports journal
2022; 9 (9): e00849
Abstract
SARS-CoV-2 mRNA vaccines are safe and effective for most patients. Gastrointestinal complications reported after vaccination have included gastroparesis and inflammatory bowel disease flares. In this study, we present a unique case of lymphocytic colitis that occurred in a healthy middle-aged man after Moderna SARS-CoV-2 mRNA vaccination. This reveals an unexpected complication of a mRNA vaccine that presented as worsening diarrhea after vaccination in a dose-dependent pattern. Caregivers should be aware of lymphocytic colitis as a possible complication of the Moderna vaccine and monitor those patients closely for symptom resolution.
View details for DOI 10.14309/crj.0000000000000849
View details for PubMedID 36134123
View details for PubMedCentralID PMC9485468
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De Novo Diagnosis of Lymphocytic Colitis After SARS-CoV-2 Vaccination
ACG CASE REPORTS JOURNAL
2022; 9 (9)
View details for DOI 10.14309/crj.0000000000000849
View details for Web of Science ID 000850933900003
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Evaluation of differential contribution of a circulating epithelial cell signal component in a multimodal colorectal neoplasia assay.
LIPPINCOTT WILLIAMS & WILKINS. 2022: E15527
View details for Web of Science ID 000863680303012
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Randomized controlled trial investigating use of submucosal injection of EverLift in rates of complete resection of non-pedunculated 4-9mm polyps.
International journal of colorectal disease
2022
Abstract
INTRODUCTION: Currently, cold snare polypectomy (CSP) without submucosal injection is recommended for removing polyps<10mm. Use of viscous submucosal agents has not been previously evaluated in CSP. We investigate the potential role of EverLift (GI Supply, Pennsylvania) in CSP.METHODS: The study is a single-center prospective randomized non-inferiority clinical trial evaluating CSP of non-pedunculated 4-9mm polyps, with or without submucosal injection of EverLift. Patients 18-80years of age presenting for colonoscopy were recruited. Eligible polyps underwent block randomization to CSP with or without EverLift. Following CSP, two biopsies were performed at the CSP site margin. The primary non-inferiority outcome was complete resection rate, defined by absence of residual polyp in the margin biopsies (non-inferiority margin-10%).RESULTS: A total of 291 eligible polyps underwent CSP, with 142 removed using EverLift. There was similar polyp size and distribution of pathology between the two groups. Overall, there was a low rate of positive margins with (1.4%) or without submucosal injection (2.8%), with no significant difference in complete resection (difference 1.28%, 95% CI:-2.66 to 5.42%), demonstrating non-inferiority of EverLift injection. Use of EverLift significantly increased CSP time (109.8 vs 38.8s, p<0.0001) and frequency of use of hemostatic clips (13.4 vs 3.6%, p=0.002).CONCLUSION: Submucosal injection of EverLift was non-inferior to CSP of 4-9mm polyps without injection and increased time for resection as well as use of hemostatic clips to control acute bleeding. Our results suggest that polypectomy of 4-9mm polyps can be safely performed without submucosal injection of EverLift.
View details for DOI 10.1007/s00384-022-04136-4
View details for PubMedID 35507047
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RANDOMIZED CONTROLLED TRIAL INVESTIGATING COLD SNARE AND FORCEPS POLYPECTOMY AMONG SMALL POLYPS IN RATES OF COMPLETE RESECTION: THE TINYPOLYP TRIAL
W B SAUNDERS CO-ELSEVIER INC. 2022: S142-S143
View details for Web of Science ID 000826446200345
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Randomized controlled Trial Investigating cold snare aNd forceps polypectomY among small POLYPs in rates of complete resection: the TINYPOLYP Trial.
The American journal of gastroenterology
2022
Abstract
BACKGROUND: Optimizing complete resection during colonoscopy is important as residual neoplastic tissue may play a role in interval cancers. The United States Multi-Society Task Force recommends diminutive (<5mm) and small (6-9mm) polyps be removed by cold snare polypectomy (CSP). However, evidence is less clear whether CSP retains significant advantage over cold forceps polypectomy (CFP) for polyps <3mm.METHODS: This study is a single-center prospective non-inferiority randomized clinical trial evaluating CFP and CSP for nonpedunculated polyps <3mm. Patients >18 years of age undergoing colonoscopy for any indication were recruited. During each colonoscopy, polyps underwent block randomization to removal with CFP or CSP. Following polypectomy, two biopsies were taken from the polypectomy margin. The primary non-inferiority outcome was complete resection rate, defined by absence of residual polyp in the margin biopsies.RESULTS: A total of 179 patients were included. Patients had similar distribution in age, sex, race/ethnicity, as well as indication of procedure. A total of 279 polyps <3mm were identified, with 138 in the CSP group and 141 in the CFP group. Mean polypectomy time was longer for CSP compared to CFP (42.3 vs 23.2 seconds, p<0.001), though a higher proportion of polyps removed by CFP were removed in more than one piece compared to CSP (15.6 vs 3.6%, p<0.001). There were positive margin biopsies in 2 cases per cohort, with complete resection rate of 98.3% in both groups. There was no significant difference in cohorts in complete resection rates (difference in complete resection rates was 0.057%, 95% CI: -4.30 to 4.53%), demonstrating non-inferiority of CFP compared to CSP.CONCLUSIONS: Use of CFP was non-inferior to CSP in the complete resection of nonpedunculated polyps <3mm. CSP required significantly more time to perform compared to CFP. CFP should be considered an acceptable alternative to CSP for removal of polyps <3mm.
View details for DOI 10.14309/ajg.0000000000001799
View details for PubMedID 35467557
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Clinical evaluation of a real-time artificial intelligence-based polyp detection system: a US multi-center pilot study.
Scientific reports
2022; 12 (1): 6598
Abstract
Artificial intelligence (AI) has increasingly been employed in multiple fields, and there has been significant interest in its use within gastrointestinal endoscopy. Computer-aided detection (CAD) can potentially improve polyp detection rates and decrease miss rates in colonoscopy. However, few clinical studies have evaluated real-time CAD during colonoscopy. In this study, we analyze the efficacy of a novel real-time CAD system during colonoscopy. This was a single-arm prospective study of patients undergoing colonoscopy with a real-time CAD system. This AI-based system had previously been trained using manually labeled colonoscopy videos to help detect neoplastic polyps (adenomas and serrated polyps). In this pilot study, 300 patients at two centers underwent elective colonoscopy with the CAD system. These results were compared to 300 historical controls consisting of consecutive colonoscopies performed by the participating endoscopists within 12months prior to onset of the study without the aid of CAD. The primary outcome was the mean number of adenomas per colonoscopy. Use of real-time CAD trended towards increased adenoma detection (1.35 vs 1.07, p=0.099) per colonoscopy though this did not achieve statistical significance. Compared to historical controls, use of CAD demonstrated a trend towards increased identification of serrated polyps (0.15 vs 0.07) and all neoplastic (adenomatous and serrated) polyps (1.50 vs 1.14) per procedure. There were significantly more non-neoplastic polyps detected with CAD (1.08 vs 0.57, p<0.0001). There was no difference in≥10mm polyps identified between the two groups. A real-time CAD system can increase detection of adenomas and serrated polyps during colonoscopy in comparison to historical controls without CAD, though this was not statistically significant. As this pilot study is underpowered, given the findings we recommend pursuing a larger randomized controlled trial to further evaluate the benefits of CAD.
View details for DOI 10.1038/s41598-022-10597-y
View details for PubMedID 35449442
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Endoscopic submucosal dissection for colorectal dysplasia in inflammatory bowel disease: a US multicenter study.
Endoscopy international open
2022; 10 (4): E354-E360
Abstract
Background and study aims In patients with inflammatory bowel disease (IBD), endoscopically visible lesions with distinct borders can be considered for endoscopic resection. The role of endoscopic submucosal dissection (ESD) for these lesions is not well defined because of a paucity of data. We aimed to evaluate the outcomes of colorectal ESD of dysplastic lesions in patients with IBD across centers in the United States. Patients and methods This was a retrospective analysis of consecutive patients with IBD who were referred for ESD of dysplastic colorectal lesions at nine centers. The primary endpoints were the rates of en bloc resection and complete (R0) resection. The secondary endpoints were the rates of adverse events and lesion recurrence. Results A total of 45 dysplastic lesions (median size 30mm, interquartile range [IQR] 23 to 42 mm) in 41 patients were included. Submucosal fibrosis was observed in 73 %. En bloc resection was achieved in 43 of 45 lesions (96 %) and R0 resection in 34 of 45 lesions (76 %). Intraprocedural perforation occurred in one patient (2.4 %) and was treated successfully with clip placement. Delayed bleeding occurred in four patients (9.8 %). No severe intraprocedural bleeding or delayed perforation occurred. During a median follow-up of 18 months (IQR 13 to 37 months), local recurrence occurred in one case (2.6 %). Metachronous lesions were identified in 11 patients (31 %). Conclusions ESD, when performed by experts, is safe and effective for large, dysplastic colorectal lesions in patients with IBD. Despite the high prevalence of submucosal fibrosis, en bloc resection was achieved in nearly all patients with IBD undergoing ESD. Careful endoscopic surveillance is necessary to monitor for local recurrence and metachronous lesions after ESD.
View details for DOI 10.1055/a-1783-8756
View details for PubMedID 35433226
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Cold Snare Resection of Small Colorectal Adenomas: The Second Time's a Charm.
Digestive diseases and sciences
2021
View details for DOI 10.1007/s10620-021-07293-8
View details for PubMedID 34731361
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Over-the-Scope Clip in the Treatment of Gastrointestinal Leaks and Perforations.
Clinical endoscopy
2021; 54 (6): 798-804
Abstract
While perforations, postoperative fistulas, and leaks have traditionally led to surgical or interventional radiology consultation for management, the introduction of the over-the-scope clip has allowed increased therapeutic possibilities for endoscopists. While primarily limited to case reports and series, the over-the-scope clip successfully manages gastrointestinal bleeding, perforations, as well as postoperative leaks and fistulas. Retrospective studies have demonstrated a relatively high success rate and a low complication rate. Given the similarity to variceal banding equipment, the learning curve with the over-the-scope clip is rapid. However, given the higher risk of procedures involving the use of the over-the-scope clip, it is essential to obtain the scope in a stable position and grasp sufficient tissue with the cap using a grasping tool and/or suction. From our experience, while closure may be successful in lesions sized up to 3 cm, successful outcomes are obtained for lesions sized <1 cm. Ultimately, given the limited available data, prospective randomized trials are needed to better evaluate the utility of the over-the-scope clip in various clinical scenarios, including fistula and perforation management.
View details for DOI 10.5946/ce.2021.250
View details for PubMedID 34872236
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Predicting Histological Diagnosis After Endoscopic Submucosal Dissection With Demographic Characteristics and Endoscopic Lesion Characteristics: An Analysis of a Large Cohort in North America
LIPPINCOTT WILLIAMS & WILKINS. 2021: S496
View details for Web of Science ID 000717526102047
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Evaluation of EverLift in the Performance of Cold Snare Polypectomy (CSP) for 4-9mm Polyps
LIPPINCOTT WILLIAMS & WILKINS. 2021: S130-S131
View details for Web of Science ID 000717526100297
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Use of the Rigidizing Overtube in Assisting Endoscopic Submucosal Dissection Among Patients With Ulcerative Colitis
LIPPINCOTT WILLIAMS & WILKINS. 2021: S880
View details for Web of Science ID 000717526103439
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Is Submucosal Injection Helpful in Cold Snare Polypectomy for Small Colorectal Polyps?
Clinical endoscopy
2021
Abstract
Background/Aims: Cold snare polypectomy (CSP) is an effective method of polyp removal for small colorectal polyps. However, the effect of submucosal injection in cold snare endoscopic mucosal resection (CS-EMR) for small polyps is unclear. Therefore, this study aimed to evaluate the effect of submucosal injection in CS-EMR for small polyps.Methods: Between 2018 and 2019, 100 consecutive small colorectal polyps (5-10 mm) were identified in 58 patients. The first 50 consecutive polyps were removed by CS-EMR, and the remaining 50 were removed by CSP. Demographic data, clinical data, endoscopic findings, procedure times, complication rates, and pathology data were collected.Results: No difference in the complete resection rate was observed between the CS-EMR and CSP groups. A total of 9 polyps showed post-polypectomy bleeding (7 had immediate bleeding, 1 had delayed bleeding, and 1 had both immediate and delayed bleeding). No difference in the bleeding rate was observed between the two groups. In multivariate analysis, warfarin (odds ratio [OR], 42.334; 95% confidence interval [CI], 1.006-1,781.758) and direct-acting oral anticoagulants (OR, 35.244; 95% CI, 3.853-322.397) showed a significantly increased risk of bleeding.Conclusions: The effect of submucosal injection in CSP was not significant for small colorectal polyps.
View details for DOI 10.5946/ce.2020.226
View details for PubMedID 33557513
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Development and clinical validation of a blood test for early detection of colorectal adenomas and cancer.
LIPPINCOTT WILLIAMS & WILKINS. 2021
View details for DOI 10.1200/JCO.2021.39.3_suppl.50
View details for Web of Science ID 000636712800105
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Endoscopic Full-Thickness Resection of Polyps Involving the Appendiceal Orifice: A Multicenter International Experience.
Endoscopy
2021
Abstract
Endoscopic resection of lesions involving the appendiceal orifice (AO) remains a challenge. We aim to report the outcomes of full-thickness resection device (FTRD) for the resection of appendiceal lesions and identify factors associated with the occurrence of appendicitis.This is a retrospective study at 18 tertiary-care centers (12 U.S., Canada 1, 5 Europe) between 11/2016 and 8/2020. Consecutive patients who underwent resection of AO lesions using the FTRD were included. The primary outcome was the rate of R0 margin resection in neoplastic lesions, defined as negative lateral and deep margins on post-resection histologic evaluation. Secondary outcomes included the rates of; technical success (en bloc resection), clinical success (technical success without need for further surgical interventions), post-resection appendicitis, and polyp recurrence.A total of 66 patients (mean age 64 yr., 29 F) underwent resection of colonic lesions (mean size 14.5 (6.2) mm) involving the AO, with 40 (61%) deep extending into the appendiceal lumen. Technical success was achieved in 59/66 (89%) cases, out of which, 56 were found to be neoplastic lesions on post-resection pathology. Clinical success was achieved in 53/66 (80%). R0 resection was achieved in 52/56 (93%) cases. Out of the 58 patients of whom EFTR was completed and had no prior history of appendectomy, appendicitis was reported in 10 (17%) cases, with 6 (60%) requiring surgical appendectomies. Follow-up colonoscopy was completed in 41 cases with evidence of recurrence in 5 (12.2%).FTRD is a promising non-surgical alternative for resecting appendiceal lesions but appendicitis occurs in 1 out of 6 cases.
View details for DOI 10.1055/a-1345-0044
View details for PubMedID 33395714
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Early Esophageal Cancer: What the Gastroenterologist Needs to Know.
Gastroenterology clinics of North America
2021; 50 (4): 791-808
Abstract
Endoscopic findings in early esophageal cancer are often subtle and require careful inspection and meticulous endoscopic examination. When dysplasia is suspected, we recommend performing 1 or 2 targeted biopsies of the abnormal area and review with a pathologist specialized in evaluating gastrointestinal diseases. In the case of adenocarcinoma, after resection of any visible cancer, residual Barrett's can be treated by ablation. Endoscopic resection can offer the opportunity for patients to avoid surgery. Further studies are needed to evaluate the optimal management of circumferential and near-circumferential lesions as well as tools and techniques to facilitate the performance of endoscopic submucosal dissection and endoscopic mucosal resection.
View details for DOI 10.1016/j.gtc.2021.07.004
View details for PubMedID 34717871
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Predictive factors for adenoma detection rates: a video study of endoscopist practices.
Endoscopy international open
2021; 9 (2): E216–E223
Abstract
Background and study aims In 2015, the American Society for Gastrointestinal Endoscopy (ASGE) and American College of Gastroenterology (ACG) Task Force on Quality in Endoscopy deemed adenoma detection rate (ADR) the most important quality measure for colonoscopy. There has been much interest in factors that can increase ADR. To date, however, few studies have looked at what intra-procedural endoscopist practices are associated with improving ADR. We conducted a retrospective review of colonoscopy videos to evaluate intra-procedural practices that could be associated with ADR. Methods Videos were recorded of colonoscopies performed between September and December 2017 at the Palo Alto Veterans Affairs Health Care System. Colonoscopies for screening and surveillance were included for video review. Factors assessed included withdrawal time, intra-procedural cleaning, inspection technique, and other variables (colon distention, removal of equivocal/hyperplastic polyps). A series of multiple regression analyses was conducted on variables of interest before running a final model of significant predictors. Results A total of 130 videos were reviewed from nine endoscopists whose ADRs ranged between 37.5 % and 73.7 %. The final regression model was significant (F = 15.35, df = 2, P = 0.0044), R 2 = 0.8365) with close inspection of behind folds and quality of cecal inspection being the factors highly correlated with predicting ADR. Withdrawal and inspection times, colonic wall distention, removal of equivocal/hyperplastic polyps, quality of rectal inspection, suctioning, and washing were factors moderately correlated with predicting ADR. Conclusions We found that behind-fold inspection and a meticulous cecal inspection technique were predictive of a high ADR.
View details for DOI 10.1055/a-1321-0990
View details for PubMedID 33553584
View details for PubMedCentralID PMC7857972
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Use of a rigidizing overtube for altered-anatomy ERCP.
VideoGIE : an official video journal of the American Society for Gastrointestinal Endoscopy
2020; 5 (12): 664–66
View details for DOI 10.1016/j.vgie.2020.08.003
View details for PubMedID 33319136
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Ideal Method for Small Bowel Preparation before Video Capsule Endoscopy.
Clinical endoscopy
2020
View details for DOI 10.5946/ce.2020.264
View details for PubMedID 33153251
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Use of a rigidizing overtube to complete an incomplete colonoscopy.
VideoGIE : an official video journal of the American Society for Gastrointestinal Endoscopy
2020; 5 (11): 583–85
View details for DOI 10.1016/j.vgie.2020.06.014
View details for PubMedID 33204926
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Efficacy of Endoscopic Submucosal Dissection for Superficial Gastric Neoplasia in a Large Cohort in North America.
Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association
2020
Abstract
BACKGROUND & AIMS: Endoscopic submucosal dissection (ESD) is a widely accepted treatment option for superficial gastric neoplasia in Asia, but there are few data on outcomes of gastric ESD from North America. We aimed to evaluate the safety and efficacy of gastric ESD in North America.METHODS: We analyzed data from 347 patients who underwent gastric ESD at 25 centers, from 2010 through 2019. We collected data on patient demographics, lesion characteristics, procedure details and related adverse events, treatment outcomes, local recurrence, and vital status at the last follow up. For the 277 patients with available follow-up data, the median interval between initial ESD and last clinical or endoscopic evaluation was 364 days. The primary endpoint was the rate of en bloc and R0 resection. Secondary outcomes included curative resection, rates of adverse events and recurrence, and gastric cancer-related death.RESULTS: Ninety patients (26%) had low-grade adenomas or dysplasia, 82 patients (24%) had high-grade dysplasia, 139 patients (40%) had early gastric cancer, and 36 patients (10%) had neuroendocrine tumors. Proportions of en bloc and R0 resection for all lesions were 92%/82%, for early gastric cancers were 94%/75%, for adenomas and low-grade dysplasia were 93%/ 92%, for high-grade dysplasia were 89%/ 87%, and for neuroendocrine tumors were 92%/75%. Intraprocedural perforation occurred in 6.6% of patients; 82% of these were treated successfully with endoscopic therapy. Delayed bleeding occurred in 2.6% of patients. No delayed perforation or procedure-related deaths were observed. There were local recurrences in 3.9% of cases; all occurred after non-curative ESD resection. Metachronous lesions were identified in 14 patients (6.9%). One of 277 patients with clinical follow up died of metachronous gastric cancer that occurred 2.5 years after the initial ESD.CONCLUSIONS: ESD is a highly effective treatment for superficial gastric neoplasia and should be considered as a viable option for patients in North America. The risk of local recurrence is low and occurs exclusively after non-curative resection. Careful endoscopic surveillance is necessary to identify and treat metachronous lesions.
View details for DOI 10.1016/j.cgh.2020.06.023
View details for PubMedID 32565290
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NOVEL RIGIDIZING OVERTUBE FOR ENTEROSCOPE/COLONOSCOPE STABILIZATION AND LOOP PREVENTION
MOSBY-ELSEVIER. 2020: AB238–AB239
View details for Web of Science ID 000545678400474
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THE RISK FACTORS OF BLEEDING IN COLD SNARE POLYPECTOMY FOR SMALL COLON POLYPS AND THE EFFECTS OF SUBMUCOSAL INJECTION
MOSBY-ELSEVIER. 2020: AB524–AB525
View details for Web of Science ID 000545678401186
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ENDOSCOPIC FULL-THICKNESS RESECTION OF POLYPS INVOLVING THE APPENDICEAL ORIFCE: FIRST MULTICENTER INTERNATIONAL STUDY
MOSBY-ELSEVIER. 2020: AB45–AB46
View details for Web of Science ID 000545678400087
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COLORECTAL ENDOSCOPIC SUBMUCOSAL DISSECTION FOR DYSPLASIA AND SUPERFICIAL NEOPLASMS IN INFLAMMATORY BOWEL DISEASE: A MULTICENTER STUDY FROM NORTH AMERICA
MOSBY-ELSEVIER. 2020: AB475
View details for Web of Science ID 000545678401084
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A sensitive and quantitative multimodal blood test for the detection of colorectal adenomas and cancer: Correlation with size and number of polyps.
AMER SOC CLINICAL ONCOLOGY. 2020
View details for Web of Science ID 000560368301077
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Long-term outcomes of per-oral endoscopic myotomy compared to laparoscopic Heller myotomy for achalasia: a single-center experience.
Surgical endoscopy
2020
Abstract
INTRODUCTION: Many centers have reported excellent short-term efficacy of per-oral endoscopic myotomy (POEM) for the treatment of achalasia. However, long-term data are limited and there are few studies comparing the efficacy of POEM versus Heller Myotomy (HM).AIMS: To compare the long-term clinical efficacy of POEM versus HM.METHODS: Using a retrospective, parallel cohort design, all cases of POEM or HM for achalasia between 2010 and 2015 were assessed. Clinical failure was defined as (a) Eckardt Score>3 for at least 4weeks, (b) achalasia-related hospitalization, or (c) repeat intervention. All index manometries were classified via Chicago Classification v3. Pre-procedural clinical, manometric, radiographic data, and procedural data were reviewed.RESULTS: 98 patients were identified (55 POEM, 43 Heller) with mean follow-up of 3.94years, and 5.44years, respectively. 83.7% of HM patients underwent associated anti-reflux wrap (Toupet or Dor). Baseline clinical, demographic, radiographic, and manometric data were similar between the groups. There was no statistical difference in overall long-term success (POEM 72.7%, HM 65.1% p=0.417, although higher rates of success were seen in Type III Achalasia in POEM vs Heller (53.3% vs 44.4%, p<0.05). Type III Achalasia was the only variable associated with failure on a univariate COX analysis and no covariants were identified on a multivariate Cox regression. There was no statistical difference in GERD symptoms, esophagitis, or major procedural complications.CONCLUSION: POEM and HM have similar long-term (4-year) efficacy with similar adverse event and reflux rates. POEM was associated with greater efficacy in Type III Achalasia.
View details for DOI 10.1007/s00464-020-07450-6
View details for PubMedID 32157405
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Novel rigidizing overtube for colonoscope stabilization and loop prevention (with video).
Gastrointestinal endoscopy
2020
Abstract
Loop formation can impede scope advancement, destabilize the tip and cause pain. Strategies to mitigate looping include torque-based reduction maneuvers, variable stiffness shafts and abdominal splinting. In some cases, these strategies are insufficient and there is need for novel instruments. Loop formation is of particular concern in colonoscopy, but it can also impact performance of other endoscopic procedures such as enteroscopy and altered-anatomy ERCP. In this case series we demonstrate the utility of a novel rigidizing overtube (Pathfinder, Neptune Medical, Burlingame, Calif, USA) in colonoscopy and other endoscopic procedures where loop management is critical.We describe our initial experience with the Pathfinder overtube in 29 patients. The overtube is 85 centimeters long and can accommodate a pediatric colonoscope. In its native state, the overtube is extremely flexible. Once the overtube is advanced to the desired location, application of a vacuum to the device causes the device to become 15 times stiffer. The endoscope can then be advanced through the overtube without loop formation in the region that the overtube traverses.The overtube was used in 29 patients to assist with difficult procedures. The patients were predominantly male (N=18; 62.1%), with median age 66 (interquartile range 57-72). One patient received an upper endoscopy (3.4%), 24 received colonoscopy (82.8%), and 4 received enteroscopy (13.8%). The overtube was used in 12 for incomplete colonoscopy (41.4%), 6 for depth (20.7%), and 11 for stability (37.9%). Colonoscopy was performed in the setting of screening (N=3), surveillance given polyp history (N=7), referrals for polyp removal (N=10), workup of iron deficiency anemia (N=2), and incomplete colonoscopy (N=1). The lower endoscopy cases had a median cecal intubation time of 5 minutes and had interquartile range (4.25 - 7 minutes). Enteroscopy was performed in 4 patients. (1) The distal 60 cm of the ileum was examined with a pediatric colonoscope to exclude ileitis. (2) The overtube was used to stabilize a 6 mm endoscope to traverse a tight Crohn's ileocolonic stricture. (3) Altered-anatomy ERCP was performed using an enteroscope through the overtube to reach a hepaticojejunostomy. (4) Upper enteroscopy was performed and the mid-jejunum was reached. We present 4 cases that demonstrate the use of the overtube. There were no adverse events.Initial experience with a novel rigidizing overtube suggests that this tool can be useful in colonoscopy and other endoscopic procedures that are affected by looping.
View details for DOI 10.1016/j.gie.2020.07.054
View details for PubMedID 32739483
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Endoscopic submucosal dissection (ESD) for Barrett's esophagus (BE)-related early neoplasia after standard endoscopic management is feasible and safe.
Endoscopy international open
2020; 8 (4): E498–E505
Abstract
Background and study aims There is little data on the feasibility and safety of endoscopic submucosal dissection (ESD) as a salvage treatment for Barrett's esophagus (BE)-related neoplasia after standard endoscopic treatments. Patients and methods A multicenter retrospective analysis on patients who underwent ESD for BE was performed. The primary endpoint was effectiveness of obtaining en-bloc resection in salvage as compared to non-salvage treatments. Results Median age was 71 (IQR 55 - 79) years. Twelve (37%) of 32 patients underwent salvage ESD. Median resection time was 100 (IQR 60 - 136) minutes. En-bloc resection was achieved in 31 patients (97 %). Complete R0 resection was obtained in 75 % in the salvage group and 80 % in the non-salvage group ( P = 1.00). In seven patients (22 %), the pre-ESD diagnosis was upgraded on post-ESD histopathology (1 low-grade dysplasia to high grade dysplasia [HGD], 4 HGD to early esophageal carcinoma (EAC), and 2 intramucosal EAC to invasive EAC). No perforations occurred in either group. Two late adverse events occurred, both in the salvage group ( P = 0.133). Delayed bleeding occurred in a patient who had just resumed warfarin and stricture occurred in a patient who had a circumferential resection requiring serial dilation and stent placement. Conclusions Our cohort study demonstrated that ESD as salvage therapy for BE related neoplasia is feasible and safe, achieving similar high rates of en-bloc resection and complete R0 resection as in treatment-naïve patients. Referral to an expert center performing ESD should be considered for patients with recurrence or progression following endoscopic mucosal resection or ablation therapy.
View details for DOI 10.1055/a-0905-2465
View details for PubMedID 32258371
View details for PubMedCentralID PMC7089792
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Water-assisted colonoscopy: an international modified Delphi review on definitions and practice recommendations.
Gastrointestinal endoscopy
2020
Abstract
Since 2008, a plethora of research studies has compared the efficacy of water-assisted (aided) colonoscopy (WAC) and underwater resection (UWR) of colorectal lesions with standard colonoscopy. We reviewed and graded the research evidence with potential clinical application. We conducted a modified Delphi consensus among experienced colonoscopists on definitions and practice of water immersion (WI), water exchange (WE), and UWR.Major databases were searched to obtain research reports that could potentially shape clinical practice related to WAC and UWR. Pertinent references were graded (Grading of Recommendations, Assessment, Development and Evaluation). Extracted data supporting evidence-based statements were tabulated and provided to respondents. We received responses from 55 (85% surveyed) experienced colonoscopists (37 experts and 18 nonexperts in WAC) from 16 countries in 3 rounds. Voting was conducted anonymously in the second and third round, with ≥80% agreement defined as consensus. We aimed to obtain consensus in all statements.In the first and the second modified Delphi rounds, 20 proposed statements were decreased to 14 and then 11 statements. After the third round, the combined responses from all respondents depicted the consensus in 11 statements (S): definitions of WI (S1) and WE (S2), procedural features (S3-S5), impact on bowel cleanliness (S6), adenoma detection (S7), pain score (S8), and UWR (S9-S11).The most important consensus statements are that WI and WE are not the same in implementation and outcomes. Because studies that could potentially shape clinical practice of WAC and UWR were chosen for review, this modified Delphi consensus supports recommendations for the use of WAC in clinical practice.
View details for DOI 10.1016/j.gie.2020.10.011
View details for PubMedID 33069706
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The Mettle to Use the Petals: Using Over-the-Scope Rings to Optimize Endoscopic Submucosal Dissection.
Digestive diseases and sciences
2020
View details for DOI 10.1007/s10620-020-06596-6
View details for PubMedID 32909123
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Risk of ambulatory colonoscopy in patients with cirrhosis: a propensity-score matched cohort study.
Endoscopy international open
2020; 8 (10): E1495–E1501
Abstract
Background and study aims Patients with cirrhosis demonstrate alterations in physiology, hemodynamics, and immunity which may increase procedural risk. There exist sparse data regarding the safety of performing ambulatory colonoscopy in patients with cirrhosis. Patients and methods From a population-based sample of three North American states (California, Florida, and New York), we collected data on 3,590 patients with cirrhosis who underwent ambulatory colonoscopy from 2009 to 2014. We created a control cohort propensity score-matched for cirrhotic severity who did not undergo colonoscopy (N = 3,590) in order to calculate the attributable risk for adverse events. The primary endpoint was the rate of unplanned hospital encounters (UHEs) within 14 days of colonoscopy (or from a synthetic index date for the control cohort). Predictors for UHE were assessed in multivariable regression. Results The attributable risk for any UHE following colonoscopy was 3.1 % (confidence interval [CI] 2.1-4.1 %, P < 0.001). There was increased risk for infection (0.9 %, CI 0.7-1.1 %), spontaneous bacterial peritonitis (0.1 %, CI 0.0-0.3 %), decompensation of ascites (0.3 %, CI 0.2-0.4 %), and cardiovascular event (0.4 %, CI 0.3-0.5 %). There was no increased attributable risk for gastrointestinal bleeding, perforation, or development of the hepatorenal syndrome. The presence of ascites at time of procedure was the only predictor for UHE in the fully-adjusted model (OR 2.6, CI 1.9-3.5, P < 0.001). Conclusions There is a moderate though detectable increase in risk for adverse event following ambulatory colonoscopy in patients with cirrhosis. The presence of ascites in particular portends higher risk. These data may guide clinicians when counseling patients with cirrhosis on the choice of colorectal cancer screening modality.
View details for DOI 10.1055/a-1242-9958
View details for PubMedID 33043119
View details for PubMedCentralID PMC7541192
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Full-thickness resection device (FTRD) for treatment of upper gastrointestinal tract lesions: the first international experience.
Endoscopy international open
2020; 8 (10): E1291–E1301
Abstract
Background and study aims The Full-Thickness Resection Device (FTRD) provides a novel treatment option for lesions not amenable to conventional endoscopic resection techniques. There are limited data on the efficacy and safety of FTRD for resection of upper gastrointestinal tract (GIT) lesions. Patients and methods This was an international multicenter retrospective study, including patients who had an endoscopic resection of an upper GIT lesion using the FTRD between January 2017 and February 2019. Results Fifty-six patients from 13 centers were included. The most common lesions were mesenchymal neoplasms (n = 23, 41 %), adenomas (n = 7, 13 %), and hamartomas (n = 6, 11 %). Eighty-four percent of lesions were located in the stomach, and 14 % in the duodenum. The average size of lesions was 14 mm (range 3 to 33 mm). Deployment of the FTRD was technically successful in 93 % of patients (n = 52) leading to complete and partial resection in 43 (77 %) and 9 (16 %) patients, respectively. Overall, the FTRD led to negative histological margins (R0 resection) in 38 (68 %) of patients. A total of 12 (21 %) mild or moderate adverse events (AEs) were reported. Follow-up endoscopy was performed in 31 patients (55 %), on average 88 days after the procedure (IQR 68-138 days). Of these, 30 patients (97 %) did not have any residual or recurrent lesion on endoscopic examination and biopsy, with residual adenoma in one patient (3 %). Conclusions Our results suggest a high technical success rate and an acceptable histologically complete resection rate, with a low risk of AEs and early recurrence for FTRD resection of upper GIT lesions.
View details for DOI 10.1055/a-1216-1439
View details for PubMedID 33015330
View details for PubMedCentralID PMC7508667
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Endoscopic Diagnosis of Nonpedunculated Dysplasia during Surveillance of Ulcerative Colitis: A Survey-Based Multinational Study.
Gut and liver
2019
Abstract
Background/Aims: Endoscopic diagnosis of dysplasia or colitic cancer in patients with ulcerative colitis (UC) is more challenging than that of colorectal neoplasia in non-colitic patients. We aimed to evaluate the accuracy of the endoscopic diagnosis of "nonpedunculated" dysplasia or colitic cancer in UC patients.Methods: Ten endoscopists from four countries were surveyed using photographs of 61 histologically confirmed dysplastic or non-dysplastic lesions retrieved from the UC registry database of Asan Medical Center. The participants provided their assessment based on the given photographs and their intention to perform biopsy.Results: The overall diagnostic performance of the 10 participants is summarized as follows: sensitivity of 88.2% (95% confidence interval [CI], 84.3% to 91.5%), specificity of 34.8% (95% CI, 29.1% to 40.8%), positive predictive value of 63.0% (95% CI, 60.8% to 65.2%), negative predictive value of 70.2% (95% CI, 62.7% to 76.6%), and accuracy of 64.6% (95% CI, 60.7% to 68.4%). The interobserver agreement on the intention to perform a biopsy was poor (Fleiss kappa=0.169). Of the three endoscopic characteristics of the lesions, including ulceration, distinctness of the borders, and pit patterns, only neoplastic pit patterns were significantly predictive of dysplasia (odds ratio, 3.710; 95% CI, 2.001 to 6.881). The diagnostic sensitivity and specificity of neoplastic pit patterns were 68.2% (95% CI, 63.0% to 73.2%) and 63.3% (95% CI, 57.3% to 69.1%), respectively.Conclusions: Diagnostic performance based on the endoscopist's intention to perform a biopsy for nonpedunculated potentially dysplastic lesions in UC patients was suboptimal according to this survey-based study.
View details for DOI 10.5009/gnl19237
View details for PubMedID 31842526
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Lumen-apposing stents versus plastic stents in the management of pancreatic pseudocysts: a large, comparative, international, multicenter study (vol 51, pg 1035, 2019)
ENDOSCOPY
2019; 51 (11): C5
View details for DOI 10.1055/a-0852-9243
View details for Web of Science ID 000494274500001
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Lumen-apposing stents versus plastic stents in the management of pancreatic pseudocysts: a large, comparative, international, multicenter study
ENDOSCOPY
2019; 51 (11): 1035-+
View details for DOI 10.1055/a-0759-1353
View details for Web of Science ID 000494274500027
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Artificial Intelligence Based Computer Aided Detection System Reliably Detects Polyps Earlier Than Physicians During Colonoscopy
LIPPINCOTT WILLIAMS & WILKINS. 2019: S159–S160
View details for DOI 10.14309/01.ajg.0000590620.15474.33
View details for Web of Science ID 000509756000273
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Novel Circulating Tumor Cell Assay for Detection of Colorectal Adenomas and Cancer.
Clinical and translational gastroenterology
2019; 10 (10): e00088
Abstract
OBJECTIVES: There is a significant unmet need for a blood test with adequate sensitivity to detect colorectal cancer (CRC) and adenomas. We describe a novel circulating tumor cell (CTC) platform to capture colorectal epithelial cells associated with CRC and adenomas.METHODS: Blood was collected from 667 Taiwanese adults from 2012 to 2018 before a colonoscopy. The study population included healthy control subjects, patients with adenomas, and those with stage I-IV CRC. CTCs were isolated from the blood using the CellMax platform. The isolated cells were enumerated, and an algorithm was used to determine the likelihood of detecting adenoma or CRC. Nominal and ordinal logistic regression demonstrated that CTC counts could identify adenomas and CRC, including CRC stage.RESULTS: The CellMax test demonstrated a significant association between CTC counts and worsening disease status (Cuzick's P value < 0.0001) with respect to the adenoma-carcinoma sequence. The test showed high specificity (86%) and sensitivity across all CRC stages (95%) and adenomatous lesions (79%). The area under the curve was 0.940 and 0.868 for the detection of CRC and adenomas, respectively.DISCUSSION: The blood-based CTC platform demonstrated high sensitivity in detecting adenomas and CRC, as well as reasonable specificity in an enriched symptomatic patient population.TRANSLATIONAL IMPACT: If these results are reproduced in an average risk population, this test has the potential to prevent CRC by improving patient compliance and detecting precancerous adenomas, eventually reducing CRC mortality.
View details for DOI 10.14309/ctg.0000000000000088
View details for PubMedID 31663904
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Radiation Training, Radiation Protection, and Fluoroscopy Utilization Practices Among US Therapeutic Endoscopists
DIGESTIVE DISEASES AND SCIENCES
2019; 64 (9): 2455–66
View details for DOI 10.1007/s10620-019-05564-z
View details for Web of Science ID 000482238300016
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Endoscopic Submucosal Dissection is Associated with Less Pathologic Uncertainty than Endoscopic Mucosal Resection in Diagnosing and Staging Barrett's- Related Neoplasia.
Digestive endoscopy : official journal of the Japan Gastroenterological Endoscopy Society
2019
Abstract
BACKGROUND & AIMS: Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have demonstrated similar efficacy in removal of neoplastic esophageal lesions. However, significant controversy exists over the preferred resection technique. Our primary aim was to compare the pathologic specimens produced via EMR and ESD and secondarily gauge their effect on clinical decision making and patient outcomes.METHODS: Using a retrospective cohort study design, all esophageal Barrett's-associated neoplastic lesions resected by a single provider (SF) from 2012-2017 were reviewed. The pathology was re-reviewed by 2 blinded authors for diagnosis, margins, and. Adverse outcomes and recurrence rates were also collected.RESULTS: 31 EMR and 20 ESD cases were identified. Baseline demographics and lesion characteristics were similar. ESD produced more R0 resections and more en bloc resections compared to EMR. EMR produced more equivocal lateral (13/31, 41.9% vs 1/20, 5.0%) and vertical margins (13/31,41.9% vs. 0/20, 0%, both p<0.05). This led to an inability to reach a definitive diagnosis in 13/31 EMR vs 0/20 ESD pathology specimens (p=.003). Of the 13 EMR specimens with equivocal pathology, 11 were noted to have 'at least intramucosal adenocarcinoma'. 4/11 patients chose to undergo elective esophagectomy with final surgical pathology demonstrating ≤T1a disease in 2, and ≥T1b disease in 2.CONCLUSION: Compared to ESD, EMR was associated with greater pathologic uncertainty in Barrett's-associated neoplasia This article is protected by copyright. All rights reserved.
View details for DOI 10.1111/den.13487
View details for PubMedID 31306525
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Endoscopic submucosal dissection in the West
INTERNATIONAL JOURNAL OF GASTROINTESTINAL INTERVENTION
2019; 8 (3): 106–9
View details for DOI 10.18528/ijgii190014
View details for Web of Science ID 000521646200002
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NON-EXPOSURE FULL-THICKNESS RESECTION OF COLONIC LESIONS IN THE U.S: THE FTRD EXPERIENCE
MOSBY-ELSEVIER. 2019: AB108
View details for Web of Science ID 000470094900108
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PROPHYLACTIC ENDOSCOPIC CLOSURE DOES NOT REDUCE ADVERSE EVENTS FOLLOWING ENDOSCOPIC SUBMUCOSAL DISSECTION: A CASE-MATCHED MULTICENTER STUDY
MOSBY-ELSEVIER. 2019: AB97
View details for Web of Science ID 000470094900090
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ARTERIOVENOUS MALFORMATIONS RESPOND POORLY TO ARGON PLASMA COAGULATION IN PATIENTS WITH CONTINUOUS FLOW LEFT VENTRICULAR ASSIST DEVICES
MOSBY-ELSEVIER. 2019: AB563–AB564
View details for Web of Science ID 000470094902365
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ENDOSCOPIC SUBMUCOSAL DISSECTION IS ASSOCIATED WITH LESS PATHOLOGIC UNCERTAINTY THAN ENDOSCOPIC MUCOSAL RESECTION IN DIAGNOSING AND STAGING BARRET'S RELATED NEOPLASIA
MOSBY-ELSEVIER. 2019: AB469–AB470
View details for Web of Science ID 000470094902159
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OUTCOMES OF ENDOSCOPIC SUBMUCOSAL DISSECTION VERSUS SURGERY IN EARLY GASTRIC CANCER MEETING STANDARD AND EXPANDED INDICATIONS: A MULTICENTER NORTH AMERICAN COHORT
MOSBY-ELSEVIER. 2019: AB350–AB351
View details for Web of Science ID 000470094901340
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ENDOSCOPIC SUBMUCOSAL DISSECTION FOR GASTRIC NEOPLASIA: A LARGE MULTICENTER STUDY FROM NORTH AMERICA
MOSBY-ELSEVIER. 2019: AB102–AB103
View details for Web of Science ID 000470094900099
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A Chance to Cut Is a Chance to Cure: Endoscopic Submucosal Dissection for Early Gastric Cancer
DIGESTIVE DISEASES AND SCIENCES
2019; 64 (5): 1129–32
View details for DOI 10.1007/s10620-018-5317-8
View details for Web of Science ID 000466886100013
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Radiation Training, Radiation Protection, and Fluoroscopy Utilization Practices Among US Therapeutic Endoscopists.
Digestive diseases and sciences
2019
Abstract
BACKGROUND: Fluoroscopy use during ERCP exposes patients and providers to deleterious effects of radiation. Formal training in fluoroscopy/radiation protection is not widely emphasized during therapeutic endoscopy training, and radiation use during GI endoscopy has not previously been characterized in the USA. In this study, we evaluated radiation training, fluoroscopy use patterns, and radiation protection practices among US therapeutic endoscopists.METHODS: An anonymous electronic survey was distributed to US therapeutic endoscopists, and responses were analyzed using descriptive statistics. State-specific requirements for fluoroscopy utilization were determined from state radiologic health branches.RESULTS: A total of 159 endoscopists (response rate 67.8%) predominantly those working in university hospitals (69.2%) with >5years of experience performing ERCP (74.9%) completed the questionnaire. Although the majority of endoscopists (61.6%) reported that they personally controlled fluoroscopy during ERCP, most (56.6%) had not received training on operating their fluoroscopy system. Only a minority (18-31%) of all respondents reported consistently utilizing modifiable fluoroscopy system parameters that minimize patient radiation exposure (pulsed fluoroscopy, frame rate modification or collimation). Endoscopists appear to undertake adequate personal radiation protective measures although use of a dosimeter was not consistent in half of respondents. The majority of states (56.8%) do not have any stated requirement for certification of non-radiologist physicians who intend to operate fluoroscopy.CONCLUSIONS: Most US gastroenterologists performing ERCP have not received formal training in operating their fluoroscopy system or in minimizing radiation exposure to themselves and to their patients. Such formal training should be included in all therapeutic endoscopy training programs, and fluoroscopy system-specific training should be offered at all hospitals.
View details for PubMedID 30911863
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Lumen apposing metal stents are superior to plastic stents in pancreatic walled-off necrosis: a large international multicenter study.
Endoscopy international open
2019; 7 (3): E347–E354
Abstract
Background and study aims The use of lumen apposing metal stents (LAMS) during EUS-guided transmural drainage (EUS-TD) of pancreatic walled-off necrosis (WON) has gained popularity. Data supporting their use in WON over plastic stents (PS), however, remain scarce. The aim of this study was to compare the clinical efficacy of LAMS (Axios, Boston Scientific) with PS in WON. Patients and methods This was a multicenter, retrospective study involving 14 centers. Consecutive patients who underwent EUS-TD of WON (2012 - 2016) were included. The primary end point was clinical success defined as WON size ≤ 3 cm within a 6-month period without need for percutaneous drainage (PCD) or surgery. Results A total of 189 patients (mean age 55.2 ± 15.6 years, 34.9 % female) were included (102 LAMS and 87 PS). Technical success rates were similar: 100 % in LAMS and 98.9 % in PS ( P = 0.28). Clinical success was attained in 80.4% of LAMS and 57.5 % of PS ( P = 0.001). Rate of PCD was similar (13.7 % LAMS vs. 16.3 % PS, P = 0.62), while PS was associated with a greater need for surgery (16.1 % PS vs. 5.6 % LAMS, P = 0.02). Adverse events (AEs) were observed in 9.8 % of LAMS and 10.3 % of PS ( P = 0.90) and were rated as severe in 2.0 % and 6.9 %, respectively ( P = 0.93). After excluding patients with < 6 months follow-up, the rate of WON recurrence following initial clinical success was greater with PS (22.9 % PS vs. 5.6 % LAMS, P = 0.04). Conclusions When compared to PS, LAMS in WON is associated with higher clinical success, shorter procedure time, lower need for surgery, and lower rate of recurrence.
View details for PubMedID 30834293
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Lumen apposing metal stents are superior to plastic stents in pancreatic walled-off necrosis: a large international multicenter study
ENDOSCOPY INTERNATIONAL OPEN
2019; 7 (3): E347-E354
View details for DOI 10.1055/a-0828-7630
View details for Web of Science ID 000460577000006
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Lumen-apposing stents versus plastic stents in the management of pancreatic pseudocysts: a large, comparative, international, multicenter study.
Endoscopy
2019
View details for PubMedID 30769348
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When Experts Fail: Use of a Short Turning Radius Colonoscope Facilitates Successful Completion of Colonoscopy in Patients with Bowel Fixity.
Digestive diseases and sciences
2019
Abstract
Rates of incomplete colonoscopy in non-expert settings range up to 13%. Expert colonoscopists can complete ~ 95% colonoscopies when other endoscopists fail; however, a small number remain incomplete even in expert hands, typically due to bowel fixity.Pentax Retroview™ (EC-3490TLi) is a new slim colonoscope with a short turning radius (STR) and greater tip deflection (210°), which allows easy maneuverability across sharply angulated/fixed colonic bends. We evaluated the utility of this colonoscope for completing colonoscopies that fail even in the hands of expert colonoscopists.Retrospective chart review was performed, and main outcomes measured included cecal intubation rate, lesions detected, dosage of sedation used, and complications.Using the STR colonoscope, complete colonoscopy to the cecum was possible in 34/37 patients (91.9%). No loss of lumen/blind advancement was necessary in any of the procedures. No adverse events occurred. Among the completed colonoscopies, 6/34 (17.6%) patients had adenomas, all proximal to the site of prior failure, including one advanced adenoma. All failures (n = 3, 8.1%) had a history of cancer surgeries, with peritoneal carcinomatosis/extensively fixed/frozen bowel (two patients) and an additional diverticular stricture with colo-vesical fistula (one patient).STR colonoscope facilitates completion of a high proportion (91.9%) of colonoscopies that previously failed in expert hands. Its STR allows easy maneuverability across segments of sharp angulation with bowel fixity without need for blind advancement. The use of this colonoscope led to the detection of adenomas in 17.6% of patients, all proximal to the site of prior failed colonoscopy.
View details for DOI 10.1007/s10620-019-05882-2
View details for PubMedID 31630343
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Arteriovenous malformations respond poorly to argon plasma coagulation in patients with continuous flow left ventricular assist devices.
European journal of gastroenterology & hepatology
2019; 31 (7): 792–98
Abstract
Gastrointestinal bleeding in patients with continuous flow left ventricular assist devices (LVADs) causes significant morbidity. Arteriovenous malformations (AVMs) cause 30-60% of bleeds, yet the efficacy of endoscopic interventions and risk factors for rebleeding have not been studied.The charts of all LVAD patients undergoing endoscopy for gastrointestinal bleeding at Stanford between January 2010 and December 2017 were reviewed. Cox proportional hazard modeling was used to evaluate risk factors for rebleeding, including the type of endoscopic treatment, patient characteristics, and endoscopic findings.Of 54 total LVAD patients presenting with gastrointestinal bleeding, 23 (42.6%) had AVMs documented on endoscopy. Treatment with argon plasma coagulation (APC) alone was associated with a higher risk of rebleeding compared to no treatment [hazard ratio (HR)=4.77, P=0.012], and compared with clip±APC (HR=7.47, P=0.012). The 90-day bleed-free rate was 10.9% with APC, 100% with clipping±APC, and 83.3% with no endoscopic treatment. Additional risk factors for rebleeding included the presence of gastric AVMs (HR=3.64, P=0.024), and presence of hematochezia (HR=5.15, P=0.05). In a multiple Cox regression model, only the presence of gastric AVMs (HR=5.50, P=0.029) and APC use (HR=14.3, P=0.008) remained significant predictors of rebleeding.The use of APC alone for the treatment of AVMs in LVAD patients had a high failure rate. The presence of gastric AVMs was a significant risk factor for rebleeding in LVAD patients. Management decisions should take these factors into account.
View details for DOI 10.1097/MEG.0000000000001427
View details for PubMedID 31150365
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Lumen-apposing stents versus plastic stents in the management of pancreatic pseudocysts: a large, comparative, international, multicenter study.
Endoscopy
2018
Abstract
BACKGROUND: Larger caliber lumen-apposing stents (LAMSs) have been increasingly used in the management of pancreatic fluid collections, specifically when solid debris is present; however, their advantages over smaller caliber plastic stents in the management of pancreatic pseudocysts are unclear. The aim of this study was to investigate the safety and efficacy of LAMS specifically in the management of pancreatic pseudocysts compared with double-pigtail plastic stents (DPPSs).METHODS: We performed a multicenter, international, retrospective study between January 2012 and August 2016. A total of 205 patients with a diagnosis of pancreatic pseudocysts were included, 80 patients received LAMSs and 125 received DPPSs. Measured outcomes included clinical success, technical success, adverse events, stent dysfunction, pancreatic pseudocyst recurrence, and need for surgery.RESULTS: Technical success was similar between the LAMS and the DPPS groups (97.5 % vs. 99.2 %; P = 0.32). Clinical success was higher for LAMSs than for DPPSs (96.3 % vs. 87.2 %; P = 0.03). While the need for surgery was similar between the two groups (1.3 % vs. 4.9 %, respectively; P = 0.17), the use of percutaneous drainage was significantly lower in the LAMS group (1.3 % vs. 8.8 %; P = 0.03). At 6-month follow-up, the recurrence rate was similar between the groups (6.7 % vs 18.8 %, respectively; P = 0.12). The rate of adverse events was significantly higher in the DPPS group (7.5 % vs. 17.6 %; P = 0.04). There was no difference in post-procedure mean length of hospital stay (6.3 days [standard deviation 27.9] vs. 3.7 days [5.7]; P = 0.31).CONCLUSION: When compared to DPPSs, LAMSs are a safe, feasible, and effective modality for the treatment of pancreatic pseudocysts and are associated with a higher rate of clinical success, shorter procedure time, less need for percutaneous interventions, and a lower overall rate of adverse events.
View details for PubMedID 30536255
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Can endoscopic resection for Barrett's dysplasia and early cancer be curative?
ANNALS OF THE NEW YORK ACADEMY OF SCIENCES
2018; 1434 (1): 54-58
View details for DOI 10.1111/nyas.13715
View details for Web of Science ID 000459386200006
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Isolated pancreatic tail remnants after transgastric necrosectomy can be observed.
The Journal of surgical research
2018; 231: 109–15
Abstract
BACKGROUND: Severe necrotizing pancreatitis may result in midbody necrosis and ductal disruption leaving an isolated pancreatic tail. The purpose of this study was to characterize outcomes among patients with an isolated tail remnant who underwent transgastric drainage or necrosectomy (endoscopic or surgical) and determine the need for subsequent operative management.MATERIALS AND METHODS: Patients with necrotizing pancreatitis and retrogastric walled-off collections treated by surgical transgastric necrosectomy or endoscopic cystgastrostomy± necrosectomy between 2009 and 2017 were identified by a retrospective chart review. All available preprocedure and postprocedure imaging was reviewed for evidence of isolated distal pancreatic tail remnants.RESULTS: Seventy-four patients were included (40 surgical and 34 endoscopic). All the patients in the surgical group underwent laparoscopic transgastric necrosectomy; the endoscopic group consisted of 26 patients for pseudocyst drainage and eight patients for necrosectomy. A disconnected pancreatic tail was identified in 22 (29%) patients (13 laparoscopic and nine endoscopic). After the creation of the "cystgastrostomy," there were no external fistulas despite the viable tail. Of the 22 patients, four patients developed symptoms at a median of 23months (two, recurrent episodic pancreatitis; two, intractable pain). Two patients (both initially in endoscopic group) ultimately required distal pancreatectomy and splenectomy at 24 and 6months after index procedure.CONCLUSIONS: Patients with a walled-off retrogastric collection and an isolated viable tail are effectively managed by a transgastric approach. Despite this seemingly "unstable anatomy," the creation of an internal fistula via surgical or endoscopic "cystgastrostomy" avoids external fistulas/drains and the short-term necessity of surgical distal pancreatectomy. A very small subset requires intervention for late symptoms.
View details for PubMedID 30278917
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Isolated pancreatic tail remnants after transgastric necrosectomy can be observed
JOURNAL OF SURGICAL RESEARCH
2018; 231: 109–15
View details for DOI 10.1016/j.jss.2018.05.020
View details for Web of Science ID 000445911700016
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Endoscopic diagnosis of non-pedunculated dysplasia during surveillance in the ulcerative colitis: A survey-based, multinational studies
WILEY. 2018: 64
View details for Web of Science ID 000450260400062
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Precision care for Barrett's esophagus.
Translational gastroenterology and hepatology
2018; 3: 67
Abstract
Modern recognition and management of Barrett's esophagus, a precursor to esophageal adenocarcinoma depends on diagnostic accuracy, risk assessment, technical expertise and consideration of many options to best tailor therapy for every patient. Concomitant management of acid reflux is essential, frequently with proton pump inhibitors. Ablation and resection favorably affect the evolution towards cancer. Using precision medicine tools, such as imaging, molecular diagnostics and analytics may lead to cost- and comparatively-effective therapies ultimately aiming at cancer prevention. Knowledge of the risk factors for Barrett's esophagus and progression to dysplasia and cancer can help tailor a precision medicine approach with more aggressive screening and surveillance targeted at patients that are most likely to benefit.
View details for DOI 10.21037/tgh.2018.09.10
View details for PubMedID 30363757
View details for PubMedCentralID PMC6182039
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Precision care for Barrett's esophagus
TRANSLATIONAL GASTROENTEROLOGY AND HEPATOLOGY
2018; 3
View details for DOI 10.21037/tgh.2018.09.10
View details for Web of Science ID 000446568500010
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Utility and performance characteristics of a novel submucosal injection agent (EleviewTM) for endoscopic mucosal resection and endoscopic submucosal dissection.
Translational gastroenterology and hepatology
2018; 3: 32
Abstract
Submucosal injection of a lifting agent is a critical step in endoscopic mucosal resection (EMR), and endoscopic submucosal dissection (ESD). Literature suggests superiority of other viscous solutions over normal saline (NS), but research to determine the ideal submucosal injection is still ongoing. In this prospective cohort study, we evaluated the utility and performance characteristics of a novel submucosal injection agent (EleviewTM) for EMR and ESD.Twelve consecutive patients referred for EMR/ESD to a tertiary referral center with experienced large polyp expert were prospectively enrolled. Ten patients with large colon polyps (mean age 66.3 years), and one patient each with esophageal and gastric lesions were included. EleviewTM was injected as submucosal lifting agent, and EMR/ESD performed. Main outcome measurements included the duration of submucosal elevation, volume and number of injections required to maintain cushion, and complications.Single injection of 3-5 cc of EleviewTM outlasted the duration of EMR. However, mean duration of cushion achieved during longer procedures (ESD) was 12.5 min, requiring several additional injections. R0 resection was achieved in 10/12 patients. One patient had minor bleeding which was managed intra-operatively.EleviewTM was successful in achieving long duration of submucosal elevation, allowing safe and efficient performance of EMR as a single injection, but needed repeated injections during longer ESD procedures. Prospective controlled trials are required to compare its performance to other available viscous submucosal solutions.
View details for DOI 10.21037/tgh.2018.06.01
View details for PubMedID 30050992
View details for PubMedCentralID PMC6043759
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Utility and performance characteristics of a novel submucosal injection agent (Eleview (TM)) for endoscopic mucosal resection and endoscopic submucosal dissection
TRANSLATIONAL GASTROENTEROLOGY AND HEPATOLOGY
2018; 3
View details for DOI 10.21037/tgh.2018.06.01
View details for Web of Science ID 000437951600001
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Underwater endoscopic mucosal resection of anal condyloma.
VideoGIE : an official video journal of the American Society for Gastrointestinal Endoscopy
2018; 3 (4): 123–24
View details for PubMedID 29917024
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Closure of large colonic defects by use of submucosal buttressedclips.
VideoGIE : an official video journal of the American Society for Gastrointestinal Endoscopy
2018; 3 (3): 87–88
View details for PubMedID 29916464
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A Chance to Cut Is a Chance to Cure: Endoscopic Submucosal Dissection for Early Gastric Cancer.
Digestive diseases and sciences
2018
View details for PubMedID 30350240
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Endoscopic Mucosal Resection with Circumferential Mucosal Incision for Colorectal Neoplasms: Comparison with Endoscopic Submucosal Dissection and between Two Endoscopists with Different Experiences
CLINICAL ENDOSCOPY
2017; 50 (4): 379–87
Abstract
Endoscopic mucosal resection with circumferential mucosal incision (CMI-EMR) may offer benefits comparable to those of endoscopic submucosal dissection (ESD), while requiring less technical proficiency than ESD.We retrospectively compared the outcomes of CMI-EMR (n=34) and size-matched ESD (n=102), which were performed by a Korean endoscopist for colorectal epithelial lesions of 20-35 mm. Procedural parameters of CMI-EMRs performed by an American ESD novice (n=30) were compared with those performed by the Korean endoscopist.The lesion size was 22.3±3.9 mm and 22.9±2.4 mm in the CMI-EMR and size-matched ESD groups, respectively (p=0.730). The resection time was 12.7±7.0 minutes in the CMI-EMR group and 45.6±30.1 minutes in the ESD group (p<0.001). The en bloc resection rate was 94.1% in the CMI-EMR group and 100% in the ESD group (p=0.061). There were no differences in the en bloc resection and complication rates of CMI-EMRs between a Korean and an American endoscopist.For the treatment of moderate-size colorectal lesions, CMI-EMR showed a trend toward lower en bloc resection rate, but required shorter procedure time than ESD. CMI-EMR outcomes were similar when performed by a Korean ESD expert and an American ESD novice.
View details for PubMedID 28264251
View details for PubMedCentralID PMC5565045
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Avulsion for the treatment of visible residual neoplasia during EMR of colorectal polyps: Is "heat" required? Response
GASTROINTESTINAL ENDOSCOPY
2017; 86 (1): 251-+
View details for PubMedID 28610865
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When Experts Fail: Short Turn Radius Colonoscope to the Rescue? Utility of a Novel Colonoscope for Incomplete Colonoscopy Due to Bowel Fixity
MOSBY-ELSEVIER. 2017: AB517
View details for DOI 10.1016/j.gie.2017.03.1191
View details for Web of Science ID 000403087401395
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Plastic Stents Are Comparable to Lumen Apposing Metal Stents in the Management of Pancreatic Pseudocysts: A Large International Multicenter Study
MOSBY-ELSEVIER. 2017: AB323
View details for DOI 10.1016/j.gie.2017.03.744
View details for Web of Science ID 000403087400712
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Lumen Apposing Stents Are Superior to Plastic Stents in the Management of Pancreatic Walled-Off Necrosis: A Large International Multicenter Study
MOSBY-ELSEVIER. 2017: AB470
View details for DOI 10.1016/j.gie.2017.03.1098
View details for Web of Science ID 000403087401294
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Closure of Large Colonic Defects Using Submucosal Buttressed Clips
MOSBY-ELSEVIER. 2017: AB146
View details for DOI 10.1016/j.gie.2017.03.298
View details for Web of Science ID 000403087400271
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Adenoma miss rates associated with a 3-minute versus 6-minute colonoscopy withdrawal time: a prospective, randomized trial.
Gastrointestinal endoscopy
2016
Abstract
The 6-minute withdrawal time for colonoscopy, widely considered the standard of care, is controversial. The skill and technique of endoscopists may be as important as, or more important than, withdrawal time for adenoma detection. It is unclear whether a shorter withdrawal time with good technique yields an acceptable lesion detection rate. Our objective was to evaluate a 3-minute versus a 6-minute withdrawal time by using segmental tandem colonoscopy.We performed a prospective, randomized trial by using 4 expert endoscopists. Patients were randomized to a 3-minute or a 6-minute initial withdrawal, each followed by a tandem second 6-minute withdrawal. All polyps were removed. The primary outcomes were adenoma miss rates (AMRs), adenomas per colonoscopy (APC) rates, and adenoma detection rates (ADRs).A total of 99 and 101 patients were enrolled in the 3-minute and 6-minute withdrawal groups, respectively. The AMR was significantly higher in the 3-minute withdrawal group (48.0% vs 22.9%; P = .0001). After controlling for endoscopist, patient age and/or sex, Boston Bowel Preparation Scale score, and size and/or location and/or morphology of adenoma, the AMR remained significantly higher in the 3-minute withdrawal group (odds ratio, 2.78; 95% confidence interval, 1.35-5.15; P = .0001). The ADR was similar between both groups (39.2% vs 40.6%; P = .84). However, the mean APC rate was significantly lower in the 3-minute withdrawal group (0.55 vs 0.80; P = .0001).The AMR was significantly higher, and the APC rate was significantly lower in the 3-minute withdrawal group versus the 6-minute withdrawal group. Despite expert technique, a shorter withdrawal time is associated with an unacceptably high AMR and low APC rate. (Clinical trial registration number: NCT01802008.).
View details for DOI 10.1016/j.gie.2016.11.030
View details for PubMedID 27931951
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EUS to the Rescue: Endoscopic Ultrasound-Guided Transgastric Cholecystostomy in Acute Cholecystitis
DIGESTIVE DISEASES AND SCIENCES
2016; 61 (12): 3436-3439
View details for DOI 10.1007/s10620-015-3974-4
View details for Web of Science ID 000388227400011
View details for PubMedID 26611858
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Endoscopic Therapy With Lumen-apposing Metal Stents Is Safe and Effective for Patients With Pancreatic Walled-off Necrosis
CLINICAL GASTROENTEROLOGY AND HEPATOLOGY
2016; 14 (12): 1797-1803
Abstract
Endoscopic ultrasound-guided transmural drainage and necrosectomy have become the standard treatment for patients with pancreatic walled-off necrosis (WON). Lumen-apposing metal stents (LAMS) have shown success in the management of pancreatic fluid collections. However, there are few data on their specific roles in management of WON. We investigated the efficacy and safety of LAMS in treatment of WON.We performed a retrospective multicenter case series of 124 patients with WON who underwent endoscopic transmural drainage by using LAMS at 17 tertiary care centers from January 2014 through May 2015. Patients underwent endoscopic ultrasound-guided cystogastrostomy or cystoenterostomy with placement of an LAMS into the WON collection. At the discretion of the endoscopist, we performed direct endoscopic necrosectomy, irrigation with hydrogen peroxide, and/or nasocystic drain placement. We performed endoscopic retrograde cholangiopancreatography with pancreatic duct stent placement when indicated. Concomitant therapies included direct endoscopic debridement (n = 78), pancreatic duct stent placement for leak (n = 19), hydrogen peroxide-assisted necrosectomy (n = 38), and nasocystic irrigation (n = 22). We collected data for a median time of 4 months (range, 1-34 months) after the LAMS placement. The primary outcomes were rates of technical success (successful placement of the LAMS), clinical success (resolution of WON, on the basis of image analysis, without need for further intervention via surgery or interventional radiology), and adverse events.The median size of the WON was 9.5 cm (range, 4-30 cm). Eight patients had 2 LAMS placed for multiport access, all with technical success (100%). Clinical success was achieved in 107 patients (86.3%) after 3 months of follow-up. Thirteen patients required a percutaneous drain, and 3 required a surgical intervention to manage their WON. The stents remained patent in 94% of patients (117 of 124) and migrated in 5.6% of patients (7 of 124). The median number of endoscopic interventions was 2 (range, 1-9 interventions).On the basis of a retrospective analysis of 124 patients, endoscopic therapy of WON by using LAMS is safe and effective. Creation of a large and sustained cystogastrostomy or cystoenterostomy tract is effective in the drainage and treatment of WON.
View details for DOI 10.1016/j.cgh.2016.05.011
View details for PubMedID 27189914
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Combining endoscopic submucosal dissection and endoscopic mucosal resection to treat neoplasia in Barrett's esophagus
SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES
2016; 30 (12): 5330-5337
Abstract
Piecemeal endoscopic mucosal resection (EMR) is the standard treatment of nodular Barrett's esophagus dysplasia and T1a cancer. Piecemeal resection may be incomplete and makes precise histologic assessment difficult. Endoscopic submucosal dissection (ESD) is a technique that enables en-bloc resection but has not gained widespread acceptance due to its technical difficulty, risk and long procedure time.We developed a protocol consisting of a combination of a limited ESD with supplementary EMR in the same session if necessary, designed to increase en-bloc resection of the most worrisome neoplastic area while maximizing the rate of complete resection of dysplasia. Records of consecutive patients referred for treatment during a 2-year period were reviewed.Eleven patients were treated: two with ESD and nine with combined ESD/EMR. Eight patients had mucosal lesions; three patients had submucosally invasive cancer and were referred to surgery. Five of the 8 mucosal lesions were removed en-bloc by ESD with dysplasia-free margins. Two patients with T1a cancer had low-grade dysplasia in the ESD margins and removal of all dysplasia on EMR. One patient with T1a cancer had high-grade dysplasia in the ESD margins and on EMR. He required a second endoscopy to remove residual neoplasia. There were no adverse events. The mean procedure time was 66.4 ± 15.1 min.Combining a limited ESD with EMR in the same session enables efficient treatment of visible dysplastic lesions in Barrett's esophagus.
View details for DOI 10.1007/s00464-016-4885-y
View details for Web of Science ID 000388111200021
View details for PubMedID 27071930
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Adenosine triphosphate bioluminescence for bacteriological surveillance and reprocessing strategies for minimizing risk of infection transmission by duodenoscopes.
Gastrointestinal endoscopy
2016
Abstract
Recent outbreaks of duodenoscope-transmitted infections underscore the importance of adequate endoscope reprocessing. Adenosine triphosphate (ATP) bioluminescence testing allows rapid evaluation of endoscopes for bacteriologic/biologic residue. In this prospective study we evaluate the utility of ATP in bacteriologic surveillance and the effects of endoscopy staff education and dual cycles of cleaning and high-level disinfection (HLD) on endoscope reprocessing.ATP bioluminescence was measured after precleaning, manual cleaning, and HLD on rinsates from suction-biopsy channels of all endoscopes and elevator channels of duodenoscopes/linear echoendoscopes after use. ATP bioluminescence was remeasured in duodenoscopes (1) after re-education and competency testing of endoscopy staff and subsequently (2) after 2 cycles of precleaning and manual cleaning and single cycle of HLD or (3) after 2 cycles of precleaning, manual cleaning, and HLD.The ideal ATP bioluminescence benchmark of <200 relative light units (RLUs) after manual cleaning was achieved from suction-biopsy channel rinsates of all endoscopes, but 9 of 10 duodenoscope elevator channel rinsates failed to meet this benchmark. Re-education reduced RLUs in duodenoscope elevator channel rinsates after precleaning (23,218.0 vs 1340.5 RLUs, P < .01) and HLD (177.0 vs 12.0 RLUs, P < .01). After 2 cycles of manual cleaning/HLD, duodenoscope elevator channel RLUs achieved levels similar to sterile water, with corresponding negative cultures.ATP testing offers a rapid, inexpensive alternative for detection of endoscope microbial residue. Re-education of endoscopy staff and 2 cycles of cleaning and HLD decreased elevator channel RLUs to levels similar to sterile water and may therefore minimize the risk of transmission of infections by duodenoscopes.
View details for DOI 10.1016/j.gie.2016.10.035
View details for PubMedID 27818222
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Avulsion is superior to argon plasma coagulation for treatment of visible residual neoplasia during EMR of colorectal polyps (with videos).
Gastrointestinal endoscopy
2016; 84 (5): 822-829
Abstract
EMR is used widely for treatment of nonpedunculated colorectal adenomas ≥ 2 cm. Recurrence at the resection site occurs in 10% to 30% of cases.Records of consecutive patients referred for endoscopic resection over a 4-year period were reviewed retrospectively. In the first part of the study period, our routine practice was to use argon plasma coagulation (APC) to treat all visible residual neoplasia after exhaustive attempts at snare resection during EMR. In the second part of the study period, we changed our practice to use avulsion to treat all visible residual neoplasia after exhaustive attempts at snare resection during EMR. We analyzed the effect of this change in practice on recurrence rates after EMR.Two hundred twenty-three resected lesions were analyzed. Fifty-nine (26%) were treated with en-bloc EMR, 55 (25%) by piecemeal EMR with complete snare removal of all visible neoplasia, 63 (28%) by piecemeal EMR with APC of visible residual neoplasia, and 46 (21%) by piecemeal EMR with avulsion of visible residual neoplasia. There was no significant difference in adverse event rates among the 4 groups. The recurrence rates on follow-up colonoscopy were 4.2%, 3.0%, 59.3%, and 10.3%, respectively. The recurrence rate for patients treated with avulsion was significantly lower than for those treated with APC (odds ratio, .079; P < .001). Multivariate analysis demonstrated that use of avulsion instead of APC was a significant predictor of no recurrence.After exhaustive attempts at snare resection during EMR, avulsion is superior to APC for treatment of residual visible neoplasia. Compared with APC, avulsion significantly decreases the recurrence rate without significantly increasing the risk of the procedure.
View details for DOI 10.1016/j.gie.2016.03.1512
View details for PubMedID 27080417
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Colonoscopy with polypectomy is associated with a low rate of complications in patients with cirrhosis.
Endoscopy international open
2016; 4 (9): E947-52
Abstract
Cirrhotic patients are at a theoretically increased risk of bleeding. The safety of polypectomy in cirrhosis is poorly defined.We performed a retrospective review of patients with cirrhosis who underwent colonoscopic polypectomy at a tertiary-care hospital. Patient characteristics and polyp data were collected. Development of complications including immediate bleeding, delayed bleeding, hospitalization, blood transfusion, perforation, and death were recorded to 30-day follow-up. Clinical characteristics between bleeders and non-bleeders were compared, and predictors of bleeding were determined.A total of 307 colonoscopies with 638 polypectomies were identified. Immediate bleeding occurred in 7.5 % (95 % CI 4.6 % - 10.4 %) and delayed bleeding occurred in 0.3 % (95 % CI 0.0 % - 0.9 %) of colonoscopies. All cases of immediate bleeding were controlled endoscopically and none resulted in serious complication. The rate of hospitalization was 0.7 % (95 % CI 0.0 % - 1.6 %) and repeat colonoscopy 0.3 % (95 % CI 0.0 % - 0.9 %); no cases of perforation, blood transfusion, or death occurred. Lower platelet count, higher INR, presence of ascites, and presence of esophageal varices were associated with increased risk of bleeding. Use of electrocautery was associated with a lower risk of immediate bleeding. There was no significant difference between bleeding and non-bleeding polyps with regard to size, morphology, and histology.Colonoscopy with polypectomy appears safe in patients with cirrhosis. There is a low risk of major complications. The risk of immediate bleeding appears higher than an average risk population; however, most bleeding is self-limited or can be controlled endoscopically. Bleeding tends to occur with more advanced liver disease. Both the sequelae of portal hypertension and coagulation abnormalities are predictive of bleeding.
View details for DOI 10.1055/s-0042-111317
View details for PubMedID 27652299
View details for PubMedCentralID PMC5025305
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Endoscopic Mucosal Resection versus Endoscopic Submucosal Dissection for Large Polyps: A Western Colonoscopist's View.
Clinical endoscopy
2016; 49 (5): 454-456
Abstract
To discuss the rationale for the widespread application of endoscopic mucosal resection (EMR) rather than endoscopic submucosal dissection (ESD) in Western centers. In Western centers, EMR is the treatment of choice for most non-pedunculated colorectal adenomas >2 cm in size. EMR is sufficiently effective and safe to be performed without post-procedure hospitalization. Advances in EMR have led to reduced recurrence rates, and recent studies have demonstrated excellent outcomes with endoscopic treatment of recurrent adenomas. While studies from Asia have demonstrated lower recurrence rates with ESD, concern about the higher perforation risk and lengthy procedure time of ESD are two of the barriers preventing widespread adoption of ESD in the West. EMR is likely to continue as the dominant method for the treatment of large colorectal adenomas in Western centers until the limitations of ESD are overcome.
View details for PubMedID 27561263
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Outcomes of endoscopic treatment of second recurrences of large nonpedunculated colorectal adenomas
SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES
2016; 30 (6): 2457-2464
Abstract
Piecemeal endoscopic mucosal resection (EMR) of large nonpedunculated colorectal adenomas is associated with significant recurrence rates. After salvage endoscopic treatment of recurrences, there is a significant rate of second recurrences. There is a paucity of data on the efficacy and safety of continued endoscopic treatment after a second recurrence.Consecutive patients with recurrent adenomas after initial piecemeal EMR of nonpedunculated colorectal adenomas >2 cm were reviewed. We assessed the feasibility, safety and efficacy of continued endoscopic treatment in these patients.Sixty-four patients with 70 recurrent lesions were identified. All were retreated endoscopically. Follow-up colonoscopy (mean interval 6.4 months) was performed on 62/70 lesions (89 %), and a second recurrence was found in 21/62 (34 %). One patient underwent surgery for a circumferential adenoma of the ileocecal valve. The other 20 lesions were treated endoscopically. Follow-up colonoscopy was performed on 15/20 (75 %) and demonstrated a third recurrence in 3/15 (20 %). One was a deep T1 cancer; curative surgery was performed. The other two patients each had one additional endoscopic treatment and both had no recurrence on subsequent colonoscopy. There were two complications: Both were delayed bleeds after treatment of the first recurrence. A mean of 1.3 endoscopic procedures was required to achieve a cure (range 1-3) for recurrent adenomas after piecemeal EMR.Endoscopic treatment of patients with second recurrences is safe and effective, but is associated with a significant rate of additional recurrences. Continued endoscopic treatment of patients with multiple recurrences is associated with high cure rates, low complication rates and a low risk of progression to malignancy.
View details for DOI 10.1007/s00464-015-4497-y
View details for PubMedID 26423413
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Minimally invasive approaches to resection of benign/low-grade gastric tumors
SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES
2016; 30 (6): 2624–25
Abstract
Tumors in the stomach have traditionally been treated with either subtotal gastrectomy or total gastrectomy, depending on the location. However, many of these lesions are benign spindle cell tumors or adenomas and could be resected with margins. Here, we explore multiple minimally invasive methods for the resection of these tumors. We highlight a wedge resection, a circumferential resection with transverse closure, a transgastric resection, and an endoscopic/laparoscopic submucosal resection. The wedge resection was performed in a 71-year-old man found to have a mass in the stomach on screening upper endoscopy. The biopsy was not definitive, but on CT scan there was a 4.5-cm submucosal mass consistent with a gastrointestinal stromal tumor. The circumferential resection was performed for an 83-year-old woman who had abdominal discomfort which led to an upper endoscopy. She was found to have a mass in the lesser curve of her stomach. Biopsy revealed this to be a gastrointestinal stromal tumor. Ultimately, it was removed when serial CT scans showed that it was growing. The transgastric approach was used for a 75-year-old man who had upper endoscopy for reflux symptoms and was found to have a mass in the stomach. Biopsy showed that it was a gastrointestinal stromal tumor. Due to patient preference, it was initially observed but was eventually removed when it was found to be growing on serial CT scans. The endoscopic/laparoscopic approach was for a 65-year-old man who had an upper endoscopy performed for work-up of melena and was found to have a 5-cm mass at the gastroesophageal junction. The biopsy showed this to be an adenoma, and he went on to have it removed.We identified representative videos from patients treated with each of the above techniques. Small exophytic lesions can be completely excised with a wedge resection using a stapler to fire across the base of the lesion. By contrast, if the lesion is in an awkward location or is too large to remove in this way, a vessel-sealing device can divide the mass from the stomach circumferentially (intragastric resection). The resultant defect in the gastric wall must be repaired transversely to avoid narrowing the lumen. Endophytic lesions can be treated with transgastric resection. Ports are placed directly into the stomach allowing excision from within the stomach. Finally, submucosal resection is ideal for lesions close to the GE junction. This combined endoscopic and laparoscopic approach allows the tumor to be lifted off the muscle fibers and to be resected without transmural injury to the stomach or esophagus.All four patients tolerated the procedure well and were discharged home by postoperative day 2. There were no complications. One patient, the one who underwent the endoscopic/laparoscopic approach and was preoperatively found to have an adenoma on biopsy, was ultimately found to have an invasive component and later underwent total gastrectomy. The other three patients all had gastrointestinal stromal tumors.Minimally invasive techniques should be considered more frequently for the management of benign gastric tumors. The four methods illustrated here can be used safely and result in faster recovery as well as shorter hospital stays compared to traditional approaches.
View details for PubMedID 26423418
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Comparative Analysis of Endoscopic Mucosal Resection With Circumferential Mucosal Incision and Endoscopic Submucosal Dissection for the Treatment of Colorectal Neoplasms
MOSBY-ELSEVIER. 2016: AB236
View details for DOI 10.1016/j.gie.2016.03.324
View details for Web of Science ID 000381906900305
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Combining Endoscopic Submucosal Dissection and Endoscopic Mucosal Resection to Treat Neoplasia in Barrett's Esophagus
MOSBY-ELSEVIER. 2016: AB558
View details for DOI 10.1016/j.gie.2016.03.1145
View details for Web of Science ID 000392524900144
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Outpatient Colorectal Endoscopic Submucosal Dissection: Results of a Practical Approach in the USA
MOSBY-ELSEVIER. 2016: AB383
View details for DOI 10.1016/j.gie.2016.03.973
View details for Web of Science ID 000392524200129
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Avulsion Is Superior to Argon Plasma Coagulation for Treatment of Visible Residual Neoplasia During Endoscopic Mucosal Resection of Colorectal Polyps
MOSBY-ELSEVIER. 2016: AB118–AB119
View details for DOI 10.1016/j.gie.2016.03.030
View details for Web of Science ID 000381906900011
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How Good Is Good Enough? Lymph Node Metastasis After Endoscopic Resection of a Rectosigmoid Polyp.
Digestive diseases and sciences
2016; 61 (3): 704-707
View details for DOI 10.1007/s10620-015-3785-7
View details for PubMedID 26134989
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Surgical Strategies for the Management of Necrotizing Pancreatitis
JOURNAL OF THE PANCREAS
2015; 16 (6): 547–58
View details for Web of Science ID 000385225400004
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The Diagnostic Yield of Endoscopic Ultrasound-Guided Fine Needle Aspiration of Subcentimeter Lesions
NATURE PUBLISHING GROUP. 2015: S664
View details for Web of Science ID 000363715903151
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Cyst Fluid Glucose is Rapidly Feasible and Accurate in Diagnosing Mucinous Pancreatic Cysts.
American journal of gastroenterology
2015; 110 (6): 909-914
Abstract
Better diagnostic tools are needed to differentiate pancreatic cyst subtypes. A previous metabolomic study showed cyst fluid glucose as a potential marker to differentiate mucinous from non-mucinous pancreatic cysts. This study seeks to validate these earlier findings using a standard laboratory glucose assay, a glucometer, and a glucose reagent strip.Using an IRB-approved prospectively collected bio-repository, 65 pancreatic cyst fluid samples (42 mucinous and 23 non-mucinous) with histological correlation were analyzed.Median laboratory glucose, glucometer glucose, and percent reagent strip positive were lower in mucinous vs. non-mucinous cysts (P<0.0001 for all comparisons). Laboratory glucose<50 mg/dl had a sensitivity of 95% and a specificity of 57% (LR+ 2.19, LR- 0.08). Glucometer glucose<50 mg/dl had a sensitivity of 88% and a specificity of 78% (LR+ 4.05, LR- 0.15). Reagent strip glucose had a sensitivity of 81% and a specificity of 74% (LR+ 3.10, LR- 0.26). CEA had a sensitivity of 77% and a specificity of 83% (LR+ 4.67, LR- 0.27). The combination of having either a glucometer glucose<50 mg/dl or a CEA level>192 had a sensitivity of 100% but a low specificity of 33% (LR+ 1.50, LR- 0.00).Glucose, whether measured by a laboratory assay, a glucometer, or a reagent strip, is significantly lower in mucinous cysts compared with non-mucinous pancreatic cysts.
View details for DOI 10.1038/ajg.2015.148
View details for PubMedID 25986360
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Predictive Factors for Surgery Among Patients with Pancreatic Cysts in the Absence of High-Risk Features for Malignancy
JOURNAL OF GASTROINTESTINAL SURGERY
2015; 19 (6): 1101-1105
Abstract
Without a reliable biopsy technique for pancreatic cysts, consensus-based guidelines are used to guide surgical utilization. The primary objective of this study was to characterize the proportion of operations performed outside of these guidelines.A 5-year retrospective review between July 1, 2007, and June 30, 2012, was performed of consecutive patients seen at a single tertiary medical center for a pancreatic cyst. Manual chart review for relevant clinical variables and cyst characteristics was performed.During this period, 148 patients underwent surgery, and of these, 23 (16 %) patients had no high-risk criteria by the 2006 Sendai criteria. None of these harbored high-grade dysplastic or cancerous lesions. A high cyst carcinoembryonic antigen (CEA) level (35 %), patient anxiety (26 %), and physician concern (22 %) were explicit reasons to proceed to surgery. An elevated cyst CEA level >192 ng/ml was the most significant predictor (OR 5.14 (95 % confidence interval (CI) 1.47-18.0) for surgery without high-risk criteria.A high cyst CEA level was significantly associated with the decision to operate outside of consensus-based guidelines. The misuse of cyst CEA in the management of pancreatic cysts negatively impacts patient anxiety, increases physician uncertainty, and leads to surgery with minimal benefit.
View details for DOI 10.1007/s11605-015-2786-3
View details for PubMedID 25749855
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Endoscopic Mucosal Resection With Circumferential Precut (Precut EMR) for Colorectal Neoplasia: Comparative Analysis With Endoscopic Submucosal Dissection
MOSBY-ELSEVIER. 2015: AB168
View details for DOI 10.1016/j.gie.2015.03.123
View details for Web of Science ID 000380763600126
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Multicenter Experience With a Lumen Apposing Stent for Walled-Off Pancreatic Necrosis (WOPN): the US Experience
MOSBY-ELSEVIER. 2015: AB161–AB162
View details for DOI 10.1016/j.gie.2015.03.109
View details for Web of Science ID 000380763600112
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Multi-Center Experience With the Cryoballoon Focal Ablation System (CAS) for Esophageal Dysplasia
MOSBY-ELSEVIER. 2015: AB522
View details for DOI 10.1016/j.gie.2015.03.1780
View details for Web of Science ID 000209931600154
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Colorectal Hybrid-ESD and ESD Outcomes in an American Referral Center
MOSBY-ELSEVIER. 2015: AB272–AB273
View details for DOI 10.1016/j.gie.2015.03.1377
View details for Web of Science ID 000209931400100
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A Real-Time Clinical Endoscopic System for Intraluminal, Multiplexed Imaging of Surface-Enhanced Raman Scattering Nanoparticles
PLOS ONE
2015; 10 (4)
Abstract
The detection of biomarker-targeting surface-enhanced Raman scattering (SERS) nanoparticles (NPs) in the human gastrointestinal tract has the potential to improve early cancer detection; however, a clinically relevant device with rapid Raman-imaging capability has not been described. Here we report the design and in vivo demonstration of a miniature, non-contact, opto-electro-mechanical Raman device as an accessory to clinical endoscopes that can provide multiplexed molecular data via a panel of SERS NPs. This device enables rapid circumferential scanning of topologically complex luminal surfaces of hollow organs (e.g., colon and esophagus) and produces quantitative images of the relative concentrations of SERS NPs that are present. Human and swine studies have demonstrated the speed and simplicity of this technique. This approach also offers unparalleled multiplexing capabilities by simultaneously detecting the unique spectral fingerprints of multiple SERS NPs. Therefore, this new screening strategy has the potential to improve diagnosis and to guide therapy by enabling sensitive quantitative molecular detection of small and otherwise hard-to-detect lesions in the context of white-light endoscopy.
View details for DOI 10.1371/journal.pone.0123185
View details for Web of Science ID 000353711600032
View details for PubMedID 25923788
View details for PubMedCentralID PMC4414592
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Radiation exposure to patients during ERCP is significantly higher with low-volume endoscopists.
Gastrointestinal endoscopy
2015; 81 (2): 391-8 e1
Abstract
Patients are exposed to radiation during ERCP, and this may increase their lifetime risk of the development of cancer and other deleterious radiation effects.To evaluate the association between the endoscopist's ERCP volume and the patient radiation dose during ERCP.Single-center, retrospective study.Tertiary referral center.A total of 197 patients undergoing 331 ERCPs.Patient radiation exposure parameters including fluoroscopy time, total radiation dose, dose area product, and effective dose for all ERCPs performed at our academic medical center by 2 high-volume endoscopists (HVEs) (≥200 ERCPs/year) and 7 low-volume endoscopists (LVEs). Radiation exposure for each ERCP was adjusted against a validated procedure complexity scale and the Stanford Fluoroscopy Complexity Score, which was created based on the numbers of interventions that would mandate additional radiation exposure.ERCPs performed by LVEs were associated with a significantly higher median total radiation dose (98.30 mGy vs 74.13 mGy), dose area product (13.98 Gy-cm(2) vs 8.8 Gy-cm(2)), and effective dose (3.63 mSv vs 2.28 mSv), despite lower median Stanford Fluoroscopy Complexity Scores (3.0 vs 6.0) compared with HVEs. No significant difference was noted in median fluoroscopy time (4.0 minutes vs 3.30 minutes) between LVEs and HVEs.Retrospective, single-center study at a tertiary referral center.ERCPs performed by LVEs are associated with significantly higher radiation exposure to patients compared with those performed by HVEs despite the fact that procedures performed by HVEs are of greater complexity.
View details for DOI 10.1016/j.gie.2014.08.001
View details for PubMedID 25293825
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Endoscopic resection of duodenal adenomas: endoscopic mucosal resection or endoscopic submucosal dissection?
ENDOSCOPY
2015; 47 (2): 99–100
View details for PubMedID 25635728
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Radiation exposure to patients during ERCP is significantly higher with low-volume endoscopists.
Gastrointestinal endoscopy
2015; 81 (2): 391-398 e1
View details for DOI 10.1016/j.gie.2014.08.001
View details for PubMedID 25293825
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Short turn radius colonoscope in an anatomical model: Retroflexed withdrawal and detection of hidden polyps.
World journal of gastroenterology
2015; 21 (2): 593-599
Abstract
To evaluate the new RetroView™ colonoscope and compare its ability to detect simulated polyps "hidden" behind colonic folds with that of a conventional colonoscope, utilizing anatomic colon models.Three anatomic colon models were prepared, with twelve simulated polyps "hidden" behind haustral folds and five placed in easily viewed locations in each model. Five blinded endoscopists examined two colon models in random order with the conventional or RetroView™ colonoscope, utilizing standard withdrawal technique. The third colon model was then examined with the RetroView™ colonoscope withdrawn initially in retroflexion and then in standard withdrawal. Polyp detection rates during standard and retroflexed withdrawal of the conventional and RetroView™ colonoscopes were determined. Polyp detection rates for combined standard and retroflexed withdrawal (combination withdrawal) with the RetroView™ colonoscope were also determined.For hidden polyps, retroflexed withdrawal using the RetroView™ colonoscope detected more polyps than the conventional colonoscope in standard withdrawal (85% vs 12%, P = 0.0001). For hidden polyps, combination withdrawal with the RetroView™ colonoscope detected more polyps than the conventional colonoscope in standard withdrawal (93% vs 12%, P ≤ 0.0001). The RetroView™ colonoscope in "combination withdrawal" was superior to other methods in detecting all (hidden + easily visible) polyps, with successful detection of 80 of 85 polyps (94%) compared to 28 (32%) polyps detected by the conventional colonoscope in standard withdrawal (P < 0.0001) and 67 (79%) polyps detected by the RetroView™ colonoscope in retroflexed withdrawal alone (P < 0.01). Continuous withdrawal of the colonoscope through the colon model while retroflexed was achieved by all endoscopists. In a post-test survey, four out of five colonoscopists reported that manipulation of the colonoscope was easy or very easy.In simulated testing, the RetroView™ colonoscope increased detection of hidden polyps. Combining standard withdrawal with retroflexed withdrawal may become the new paradigm for "complete screening colonoscopy".
View details for DOI 10.3748/wjg.v21.i2.593
View details for PubMedID 25593483
View details for PubMedCentralID PMC4294171
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A real-time clinical endoscopic system for intraluminal, multiplexed imaging of surface-enhanced Raman scattering nanoparticles.
PloS one
2015; 10 (4)
Abstract
The detection of biomarker-targeting surface-enhanced Raman scattering (SERS) nanoparticles (NPs) in the human gastrointestinal tract has the potential to improve early cancer detection; however, a clinically relevant device with rapid Raman-imaging capability has not been described. Here we report the design and in vivo demonstration of a miniature, non-contact, opto-electro-mechanical Raman device as an accessory to clinical endoscopes that can provide multiplexed molecular data via a panel of SERS NPs. This device enables rapid circumferential scanning of topologically complex luminal surfaces of hollow organs (e.g., colon and esophagus) and produces quantitative images of the relative concentrations of SERS NPs that are present. Human and swine studies have demonstrated the speed and simplicity of this technique. This approach also offers unparalleled multiplexing capabilities by simultaneously detecting the unique spectral fingerprints of multiple SERS NPs. Therefore, this new screening strategy has the potential to improve diagnosis and to guide therapy by enabling sensitive quantitative molecular detection of small and otherwise hard-to-detect lesions in the context of white-light endoscopy.
View details for DOI 10.1371/journal.pone.0123185
View details for PubMedID 25923788
View details for PubMedCentralID PMC4414592
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The learning curve for detection of non-polypoid (flat and depressed) colorectal neoplasms.
Gut
2015; 64 (1): 184-185
View details for DOI 10.1136/gutjnl-2013-305743
View details for PubMedID 23946382
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Effect of prior biopsy sampling, tattoo placement, and snare sampling on endoscopic resection of large nonpedunculated colorectal lesions
GASTROINTESTINAL ENDOSCOPY
2015; 81 (1): 204-213
Abstract
Endoscopic manipulations, including biopsy sampling, tattoo application on the lesion itself, and sampling of the lesion with a polypectomy snare, are frequently performed on large nonpedunculated colorectal lesions ≥ 20 mm (LNCL) before referral for endoscopic resection.To assess the effect of prior manipulations on the technical difficulty and recurrence rates of subsequent endoscopic treatment.Retrospective study.Two referral centers.Patients with LNCL referred for endoscopic resection.Endoscopic resection.En-bloc resection rate, rate of successful complete endoscopic resection without the need for ablation of visible residual, recurrence rate on follow-up, independent predictive factors for en-bloc resection, complete resection without ablation of visible residual, and recurrence.A total of 132 lesions was analyzed: 46 lesions without any prior manipulation, 44 with prior biopsy sampling only, and 42 with prior advanced manipulation including tattoo and/or snare sampling. The en-bloc resection rate was 34.8% for nonmanipulated lesions, 15.9% for lesions with prior biopsy sampling, and 4.8% for lesions with prior advanced manipulation (P = .001). Complete endoscopic resection without the need for ablation of visible residual was performed in 93.5% of nonmanipulated lesions, 68.2% of lesions with prior biopsy sampling, and 50% of lesions with prior advanced manipulation (P < .001). Recurrence rates were 7.7%, 40.7%, and 53.8% in the 3 groups (P = .001). In multivariate analysis, prior biopsy sampling was an independent predictor for inability to perform complete resection without ablation of visible residual (odds ratio .24, P < .05) and for recurrence (odds ratio 11.5, P = .004) compared with nonmanipulated lesions. Prior advanced manipulation was an independent predictor for inability to perform en-bloc resection (odds ratio .024, P = .001), for inability to perform complete resection without ablation of visible residual (odds ratio .081, P < .001), and for recurrence (odds ratio 18.8, P = .001).Retrospective study.Prior biopsy sampling and advanced manipulation have significant deleterious effects on endoscopic treatment of LNCL.
View details for DOI 10.1016/j.gie.2014.08.038
View details for PubMedID 25440686
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Underwater endoscopic mucosal resection for recurrences after previous piecemeal resection of colorectal polyps
GASTROINTESTINAL ENDOSCOPY
2014; 80 (6): 1094-1102
Abstract
Conventional endoscopic treatment of a recurrent adenoma after piecemeal EMR (PEMR) of a colorectal laterally spreading tumor (LST) is technically difficult with low en bloc resection rates because of the inability to snare fibrotic residual.To assess the feasibility of salvage underwater EMR (UEMR) for the treatment of recurrent adenoma after PEMR of a colorectal LST.Retrospective, cross-sectional study.Single, tertiary-care referral center.Patients who have recurrent adenoma after PEMR of colorectal LST (≥2 cm).UEMR versus EMR.En bloc resection rate, endoscopic complete removal rate, recurrence rate on follow-up colonoscopy, adjunctive ablation rate with argon plasma coagulation (APC) during salvage procedure, and independent predictive factors for successful en bloc resection and endoscopic complete removal.Eighty salvage procedures (36 UEMRs vs 44 EMRs) were analyzed. En bloc resection rate (47.2% vs 15.9%, P = .002) and endoscopic complete removal rate (88.9% vs 31.8%, P < .001) were higher in the UEMR group than in the EMR group. APC ablation of visible residual during salvage procedure was lower in UEMR group than EMR group (11.1% vs 65.9%, P < .001). Recurrence rate on follow-up colonoscopy was significantly lower in the UEMR group than the EMR group (10% vs 39.4%, P = .02). UEMR was an independent predictor of successful en bloc resection and endoscopic complete removal.Retrospective, single-center study.UEMR can be a useful and feasible technique as a salvage procedure for recurrent colorectal adenoma after PEMR.
View details for DOI 10.1016/j.gie.2014.05.318
View details for PubMedID 25012560
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Rapid Point-of-Care Measurement of Cyst Fluid Glucose Is Feasible and Accurate in Predicting Mucinous Pancreatic Cysts
NATURE PUBLISHING GROUP. 2014: S86
View details for Web of Science ID 000344383100280
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Safe and effective colon polypectomy in patients receiving uninterrupted anticoagulation: can we do it?
GASTROINTESTINAL ENDOSCOPY
2014; 79 (3): 424–46
View details for PubMedID 24528826
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Outcomes of repeat colonoscopy in patients with polyps referred for surgery without biopsy-proven cancer
GASTROINTESTINAL ENDOSCOPY
2014; 79 (1): 101-107
Abstract
Despite advances in endoscopic treatment, many colonic adenomas are still referred for surgical resection. There is a paucity of data on the suitability of these lesions for endoscopic treatment.To analyze the results of routine repeat colonoscopy in patients referred for surgical resection of colon polyps without biopsy-proven cancer.Retrospective review.University hospital.Patients referred to a colorectal surgeon for surgical resection of a polyp without biopsy-proven cancer.Repeat colonoscopy.The rate of successful endoscopic treatment.There were 38 lesions in 36 patients; 71% of the lesions were noncancerous and were successfully treated endoscopically. In 26% of the lesions, previous removal was attempted by the referring physician but was unsuccessful. The adenoma recurrence rate was 50%, but all recurrences were treated endoscopically and none were cancerous. Two patients were admitted for overnight observation. There were no major adverse events.Single center, retrospective.In the absence of biopsy-proven invasive cancer, it is appropriate to reevaluate patients referred for surgical resection by repeat colonoscopy at an expert center.
View details for DOI 10.1016/j.gie.2013.06.034
View details for Web of Science ID 000328736700018
View details for PubMedID 23916398
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Treatment of nonampullary sporadic duodenal adenomas with endoscopic mucosal resection or ablation.
Digestive diseases and sciences
2013; 58 (10): 2751-2752
View details for DOI 10.1007/s10620-013-2787-6
View details for PubMedID 23884756
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Metabolomic-derived novel cyst fluid biomarkers for pancreatic cysts: glucose and kynurenine.
Gastrointestinal endoscopy
2013; 78 (2): 295-302 e2
Abstract
BACKGROUND: Better pancreatic cyst fluid biomarkers are needed. OBJECTIVE: To determine whether metabolomic profiling of pancreatic cyst fluid would yield clinically useful cyst fluid biomarkers. DESIGN: Retrospective study. SETTING: Tertiary-care referral center. PATIENTS: Two independent cohorts of patients (n = 26 and n = 19) with histologically defined pancreatic cysts. INTERVENTION: Exploratory analysis for differentially expressed metabolites between (1) nonmucinous and mucinous cysts and (2) malignant and premalignant cysts was performed in the first cohort. With the second cohort, a validation analysis of promising identified metabolites was performed. MAIN OUTCOME MEASUREMENTS: Identification of differentially expressed metabolites between clinically relevant cyst categories and their diagnostic performance (receiver operating characteristic [ROC] curve). RESULTS: Two metabolites had diagnostic significance-glucose and kynurenine. Metabolomic abundances for both were significantly lower in mucinous cysts compared with nonmucinous cysts in both cohorts (glucose first cohort P = .002, validation P = .006; and kynurenine first cohort P = .002, validation P = .002). The ROC curve for glucose was 0.92 (95% confidence interval [CI], 0.81-1.00) and 0.88 (95% CI, 0.72-1.00) in the first and validation cohorts, respectively. The ROC for kynurenine was 0.94 (95% CI, 0.81-1.00) and 0.92 (95% CI, 0.76-1.00) in the first and validation cohorts, respectively. Neither could differentiate premalignant from malignant cysts. Glucose and kynurenine levels were significantly elevated for serous cystadenomas in both cohorts. LIMITATIONS: Small sample sizes. CONCLUSION: Metabolomic profiling identified glucose and kynurenine to have potential clinical utility for differentiating mucinous from nonmucinous pancreatic cysts. These markers also may diagnose serous cystadenomas.
View details for DOI 10.1016/j.gie.2013.02.037
View details for PubMedID 23566642
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Metabolomic-derived novel cyst fluid biomarkers for pancreatic cysts: glucose and kynurenine
GASTROINTESTINAL ENDOSCOPY
2013; 78 (2): 295-?
Abstract
BACKGROUND: Better pancreatic cyst fluid biomarkers are needed. OBJECTIVE: To determine whether metabolomic profiling of pancreatic cyst fluid would yield clinically useful cyst fluid biomarkers. DESIGN: Retrospective study. SETTING: Tertiary-care referral center. PATIENTS: Two independent cohorts of patients (n = 26 and n = 19) with histologically defined pancreatic cysts. INTERVENTION: Exploratory analysis for differentially expressed metabolites between (1) nonmucinous and mucinous cysts and (2) malignant and premalignant cysts was performed in the first cohort. With the second cohort, a validation analysis of promising identified metabolites was performed. MAIN OUTCOME MEASUREMENTS: Identification of differentially expressed metabolites between clinically relevant cyst categories and their diagnostic performance (receiver operating characteristic [ROC] curve). RESULTS: Two metabolites had diagnostic significance-glucose and kynurenine. Metabolomic abundances for both were significantly lower in mucinous cysts compared with nonmucinous cysts in both cohorts (glucose first cohort P = .002, validation P = .006; and kynurenine first cohort P = .002, validation P = .002). The ROC curve for glucose was 0.92 (95% confidence interval [CI], 0.81-1.00) and 0.88 (95% CI, 0.72-1.00) in the first and validation cohorts, respectively. The ROC for kynurenine was 0.94 (95% CI, 0.81-1.00) and 0.92 (95% CI, 0.76-1.00) in the first and validation cohorts, respectively. Neither could differentiate premalignant from malignant cysts. Glucose and kynurenine levels were significantly elevated for serous cystadenomas in both cohorts. LIMITATIONS: Small sample sizes. CONCLUSION: Metabolomic profiling identified glucose and kynurenine to have potential clinical utility for differentiating mucinous from nonmucinous pancreatic cysts. These markers also may diagnose serous cystadenomas.
View details for DOI 10.1016/j.gie.2013.02.037
View details for Web of Science ID 000321825200015
View details for PubMedID 23566642
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A Raman-based endoscopic strategy for multiplexed molecular imaging.
Proceedings of the National Academy of Sciences of the United States of America
2013; 110 (25): E2288-97
Abstract
Endoscopic imaging is an invaluable diagnostic tool allowing minimally invasive access to tissues deep within the body. It has played a key role in screening colon cancer and is credited with preventing deaths through the detection and removal of precancerous polyps. However, conventional white-light endoscopy offers physicians structural information without the biochemical information that would be advantageous for early detection and is essential for molecular typing. To address this unmet need, we have developed a unique accessory, noncontact, fiber optic-based Raman spectroscopy device that has the potential to provide real-time, multiplexed functional information during routine endoscopy. This device is ideally suited for detection of functionalized surface-enhanced Raman scattering (SERS) nanoparticles as molecular imaging contrast agents. This device was designed for insertion through a clinical endoscope and has the potential to detect and quantify the presence of a multiplexed panel of tumor-targeting SERS nanoparticles. Characterization of the Raman instrument was performed with SERS particles on excised human tissue samples, and it has shown unsurpassed sensitivity and multiplexing capabilities, detecting 326-fM concentrations of SERS nanoparticles and unmixing 10 variations of colocalized SERS nanoparticles. Another unique feature of our noncontact Raman endoscope is that it has been designed for efficient use over a wide range of working distances from 1 to 10 mm. This is necessary to accommodate for imperfect centering during endoscopy and the nonuniform surface topology of human tissue. Using this endoscope as a key part of a multiplexed detection approach could allow endoscopists to distinguish between normal and precancerous tissues rapidly and to identify flat lesions that are otherwise missed.
View details for DOI 10.1073/pnas.1211309110
View details for PubMedID 23703909
View details for PubMedCentralID PMC3690865
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A Raman-based endoscopic strategy for multiplexed molecular imaging
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2013; 110 (25): 10062–63
View details for Web of Science ID 000321500200020
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A Raman-based endoscopic strategy for multiplexed molecular imaging.
Proceedings of the National Academy of Sciences of the United States of America
2013; 110 (25): E2288-97
View details for DOI 10.1073/pnas.1211309110
View details for PubMedID 23703909
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Endoscopic management of nonlifting colon polyps.
Diagnostic and therapeutic endoscopy
2013; 2013: 412936-?
Abstract
Background and Study Aims. The nonlifting polyp sign of invasive colon cancer is considered highly sensitive and specific for cancer extending beyond the mid-submucosa. However, prior interventions can cause adenomas to become nonlifting due to fibrosis. It is unclear whether nonlifting adenomas can be successfully treated endoscopically. The aim of this study was to evaluate outcomes in a referral practice incorporating a standardized protocol of attempted endoscopic resection of nonlifting lesions previously treated by biopsy, polypectomy, surgery, or tattoo placement. Patients and Methods. Retrospective review of patients undergoing colonoscopy by one endoscopist at two hospitals found to have nonlifting lesions from prior interventions. Lesions with biopsy proven invasive cancer or definite endoscopic features of invasive cancer were excluded. Lesions ≥ 8 mm were routinely injected with saline prior to attempted endoscopic resection. Polypectomy was performed using a stiff snare, followed by argon plasma coagulation (APC) if necessary. Results. 26 patients each had a single nonlifting lesion with a history of prior intervention. Endoscopic resection was completed in 25 (96%). 22 required snare resection and APC. 1 patient had invasive cancer and was referred for surgery. The recurrence rate on follow-up colonoscopy was 26%. All of the recurrences were successfully treated endoscopically. There was 1 postprocedure bleed (4%), no perforations, and no other complications. Conclusions. The majority of adenomas that are nonlifting after prior interventions can be treated successfully and safely by a combination of piecemeal polypectomy and ablation. Although recurrence rates are high at 26%, these too can be successfully treated endoscopically.
View details for DOI 10.1155/2013/412936
View details for PubMedID 23761952
View details for PubMedCentralID PMC3666422
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Diagnostic Utility of Metabolomic-Derived Biomarkers for Pancreatic Cysts
LIPPINCOTT WILLIAMS & WILKINS. 2012: 1394–94
View details for Web of Science ID 000310360500241
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Water-aided colonoscopy: a systematic review
GASTROINTESTINAL ENDOSCOPY
2012; 76 (3): 657-666
Abstract
Water-aided methods for colonoscopy are distinguished by the timing of removal of infused water, predominantly during withdrawal (water immersion) or during insertion (water exchange).To discuss the impact of these approaches on colonoscopy pain and adenoma detection rate (ADR).Systematic review.Randomized, controlled trial (RCT) that compared water-aided methods and air insufflation during colonoscope insertion.Patients undergoing colonoscopy.Medline, PubMed, and Google searches (January 2008-December 2011) and personal communications of manuscripts in press were considered to identify appropriate RCTs.Pain during colonoscopy and ADR. RCTs were grouped according to whether water immersion or water exchange was used. Reported pain scores and ADR were tabulated based on group assignment.Pain during colonoscopy is significantly reduced by both water immersion and water exchange compared with traditional air insufflation. The reduction in pain scores was qualitatively greater with water exchange as compared with water immersion. A mixed pattern of increases and decreases in ADR was observed with water immersion. A higher ADR, especially proximal to the splenic flexure, was obtained when water exchange was implemented.Differences in the reports limit application of meta-analysis. The inability to blind the colonoscopists exposed the observations to uncertain bias.Compared with air insufflation, both water immersion and water exchange significantly reduce colonoscopy pain. Water exchange may be superior to water immersion in minimizing colonoscopy discomfort and in increasing ADR. A head-to-head comparison of these 3 approaches is required.
View details for DOI 10.1016/j.gie.2012.04.467
View details for Web of Science ID 000307948600028
View details for PubMedID 22898423
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Is colonoscopy best learned underwater?
Journal of interventional gastroenterology
2012; 2 (3): 140-141
View details for PubMedID 23805396
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The water exchange method for colonoscopy-effect of coaching.
Journal of interventional gastroenterology
2012; 2 (3): 122-125
Abstract
The growing popularity of water immersion is supported by its long history as an adjunct to air insufflation; after facilitating colonoscope passage, the infused water is conveniently removed during withdrawal. Water exchange, a modification of water immersion to minimize discomfort in scheduled unsedated patients in the U.S. is new. Even though it may be superior in reducing pain and increasing adenoma detection, the paradigm shift to complete exclusion of air during insertion necessitates removal of infused water containing residual feces, a step often perceived as laborious and time-consuming. The nuances are the efficient steps to remove infused water predominantly during insertion to maintain minimal distension and deliver salvage cleansing. Mastery of the novel maneuvers with practice returns insertion time towards baseline. In this observational study the impact of direct verbal coaching on the primary outcome of intention-to-treat cecal intubation was assessed. The results showed that 14 of 19 (74%) experienced colonoscopists achieved 100% intention-to-treat cecal intubation. Initiation of the examination with water exchange did not preclude completion when conversion to the more familiar air insufflation method was deemed necessary to achieve cecal intubation (total 98%). The overall intention-to-treat cecal intubation rate was 88%, 90% in male and 87% in female. Only 2.7% of bowel preparation was rated as poor during withdrawal. The mean volume of water infused and cecal intubation time was 1558 ml and 18 min, respectively. Direct coaching appears to facilitate understanding of the nuances of the water exchange method. Studies of individual learning curves are necessary.
View details for PubMedID 23805391
View details for PubMedCentralID PMC3655365
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Endoscopic mucosal resection with an over-the-counter hyaluronate preparation
GASTROINTESTINAL ENDOSCOPY
2012; 75 (5): 1040-1044
Abstract
Hyaluronic acid (HA) provides a long-lasting and distinct mucosal elevation for EMR, but expense and inconvenience have limited its adoption.To evaluate the safety and efficacy of an over-the-counter 0.15% HA preparation for EMR.Retrospective study.Veterans Administration Hospital and university hospital.30 patients with a total of 32 colonic lesions and 1 duodenal lesion.EMR by using HA.En bloc resection rate and complications.EMR was successful in all cases. En bloc resection was achieved in 26 of the 28 lesions up to 25 mm in diameter. Two lesions, both with fibrosis from prior attempted resection, had trace residual tissue necessitating cauterization with argon plasma. Five lesions measuring 30 mm to 60 mm all required piecemeal resection. There was one complication, a postpolypectomy bleed.Small number of patients and retrospective design.EMR may be performed safely and effectively by using an inexpensive, over-the-counter 0.15% HA preparation. Further studies are needed to verify the results of this study and to compare the safety and efficacy of this HA preparation with saline solution.
View details for DOI 10.1016/j.gie.2012.01.010
View details for Web of Science ID 000303277400016
View details for PubMedID 22381528
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Radiation Exposure to Patients During ERCP Is Significantly Higher With Low Volume Endoscopists
53rd Annual Meeting of the Society-for-Surgery-of-the-Alimentary-Tract (SSAT) / Digestive Disease Week (DDW) / Meeting of the Pancreas-Club
MOSBY-ELSEVIER. 2012: 140–41
View details for Web of Science ID 000304328000119
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The Learning Curve for Detection of Nonpolypoid (Flat and Depressed) Colorectal Neoplasms
MOSBY-ELSEVIER. 2012: 177–78
View details for Web of Science ID 000304328001007
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Post-Procedural Reading of ERCP Spot Films by Radiologists: Has it Improved in the Era of Electronic Medical Records?
53rd Annual Meeting of the Society-for-Surgery-of-the-Alimentary-Tract (SSAT) / Digestive Disease Week (DDW) / Meeting of the Pancreas-Club
MOSBY-ELSEVIER. 2012: 137–38
View details for Web of Science ID 000304328000112
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A New Colonoscope With a Short Turn Radius Allowing Full Withdrawal in Complete Retroflexion Improves Detection of Simulated Polyps Hidden Behind Folds and Flexures in Anatomic Colon Models
53rd Annual Meeting of the Society-for-Surgery-of-the-Alimentary-Tract (SSAT) / Digestive Disease Week (DDW) / Meeting of the Pancreas-Club
MOSBY-ELSEVIER. 2012: 215–15
View details for Web of Science ID 000304328001116
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Water Exchange May Be Superior to Water Immersion Minimizes Colonoscopy Discomfort and Increases Adenoma Detection Rate (ADR) - Review of Recent Randomized Controlled Trials (RCT)
53rd Annual Meeting of the Society-for-Surgery-of-the-Alimentary-Tract (SSAT) / Digestive Disease Week (DDW) / Meeting of the Pancreas-Club
MOSBY-ELSEVIER. 2012: 276–76
View details for Web of Science ID 000304328001300
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Endoscopic Mucosal Resection Using an Inexpensive Over the Counter Hyaluronate Preparation
53rd Annual Meeting of the Society-for-Surgery-of-the-Alimentary-Tract (SSAT) / Digestive Disease Week (DDW) / Meeting of the Pancreas-Club
MOSBY-ELSEVIER. 2012: 344–45
View details for Web of Science ID 000304328001497
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Comparison of EUS-Guided Pancreas Biopsy Techniques Using the Procore (TM) Needle
53rd Annual Meeting of the Society-for-Surgery-of-the-Alimentary-Tract (SSAT) / Digestive Disease Week (DDW) / Meeting of the Pancreas-Club
MOSBY-ELSEVIER. 2012: 145–45
View details for Web of Science ID 000304328000131
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Is EGD Necessary in Patients With Positive Fecal Occult Blood Test and Negative Colonoscopy?
53rd Annual Meeting of the Society-for-Surgery-of-the-Alimentary-Tract (SSAT) / Digestive Disease Week (DDW) / Meeting of the Pancreas-Club
MOSBY-ELSEVIER. 2012: 139–40
View details for Web of Science ID 000304328000117
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A tandem colonoscopy study of adenoma miss rates during endoscopic training: a venture into uncharted territory
GASTROINTESTINAL ENDOSCOPY
2012; 75 (3): 561-567
Abstract
Tandem colonoscopy is regarded as the reference standard for the evaluation of the adenoma detection rate (ADR) and adenoma miss rate (AMR) during colonoscopy. Pooled results from previous tandem studies yield AMRs of 22%. The AMR of trainees is important to estimate the number of colonoscopies required to develop competence in screening for colorectal neoplasms.To measure the ADR and AMR of trainees as a function of experience.Prospective tandem colonoscopy study at an academic VA medical center. A trainee initially attempted colonoscopy. If the trainee was able to intubate the cecum, the trainee performed the withdrawal, and the colonoscopy was then repeated by the attending physician to assess the AMR.Twelve trainee endoscopists were included in the study. Trainees had between 0 and 33 months of previous endoscopic experience and had done between 0 and 605 previous colonoscopies. A total of 230 patients were evaluated for the study, and 218 patients were enrolled. Complete tandem colonoscopy was performed in 147 patients. There was a 54% ADR. The mean (standard deviation) size of the adenomas in the cohort was 5.9 (5.3) mm. Significant variables in multivariate logistic regression analysis for missed adenomas were trainee experience (P = .011) and patient age (P < .001). The AMR decreased with increasing experience, and it is estimated that 450 colonoscopies are required to attain AMRs of less than 25% in a 60-year-old patient.Single-center study; the attending physician performing the second pass was not blinded to the first pass. The AMR was only analyzed for cases in which the trainee was able to reach the cecum with no or minimal assistance.Our tandem colonoscopy study demonstrates that the AMR decreases as the experience of trainees increases and is a late competency attained during training. Future training may need to incorporate these findings to serve as a basis for determining appropriate training guidelines.
View details for DOI 10.1016/j.gie.2011.11.037
View details for Web of Science ID 000301319900017
View details for PubMedID 22341103
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Proficiency in the Diagnosis of Nonpolypoid Colorectal Neoplasm Yields High Adenoma Detection Rates
DIGESTIVE DISEASES AND SCIENCES
2012; 57 (3): 764-770
Abstract
Current efforts to prevent colorectal cancer focus on the detection and removal of neoplasms. Nonpolypoid colorectal neoplasms (NP-CRN) have a subtle appearance that can be difficult to recognize during colonoscopy. Endoscopists must first be familiar with the patterns of NP-CRN in order to detect and diagnose them. We studied the adenoma detection rates of endoscopists who had trained to detect NP-CRN, versus endoscopists who had not.Design: Retrospective Nested Case Control Study. Setting: Outpatient Screening Colonoscopy. Participants: Adult Veterans. Intervention: Proficiency in the features and diagnosis of NP-CRN. Main Outcomes Measurements: Adenoma detection.In total, 462 patients had screening colonoscopies-267 by colonoscopists who had trained in the features and diagnosis of NP-CRN. Patient characteristics were similar between groups-the majority were men with a mean age of 62 ± 6 years. Neoplasia was more prevalent (45.7 vs. 34.9%; p = 0.02) in patients evaluated by the trained compared to the conventionally trained group. Trained colonoscopists had a higher adenoma detection rate (0.76 vs. 0.54 adenomas per patient, p < 0.001); removed a higher proportion of neoplasia (77 vs. 35%, p < 0.001); and more frequently diagnosed NP-CRN lesions (OR 2.98, 95% CI: 1.46-6.08) compared to colonoscopists without supplemental training.Endoscopists who are proficient in the detection of NP-CRN had significantly higher adenoma detection rates-of both polypoid and flat adenomas-compared to endoscopists without training, and were more specific in resection of adenomatous over hyperplastic lesions.
View details for DOI 10.1007/s10620-011-1921-6
View details for Web of Science ID 000300578200024
View details for PubMedID 21964768
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Diagnostic accuracy of cyst fluid amphiregulin in pancreatic cysts
BMC GASTROENTEROLOGY
2012; 12
Abstract
Accurate tests to diagnose adenocarcinoma and high-grade dysplasia among mucinous pancreatic cysts are clinically needed. This study evaluated the diagnostic utility of amphiregulin (AREG) as a pancreatic cyst fluid biomarker to differentiate non-mucinous, benign mucinous, and malignant mucinous cysts.A single-center retrospective study to evaluate AREG levels in pancreatic cyst fluid by ELISA from 33 patients with a histological gold standard was performed.Among the cyst fluid samples, the median (IQR) AREG levels for non-mucinous (n = 6), benign mucinous (n = 15), and cancerous cysts (n = 15) were 85 pg/ml (47-168), 63 pg/ml (30-847), and 986 pg/ml (417-3160), respectively. A significant difference between benign mucinous and malignant mucinous cysts was observed (p = 0.025). AREG levels greater than 300 pg/ml possessed a diagnostic accuracy for cancer or high-grade dysplasia of 78% (sensitivity 83%, specificity 73%).Cyst fluid AREG levels are significantly higher in cancerous and high-grade dysplastic cysts compared to benign mucinous cysts. Thus AREG exhibits potential clinical utility in the evaluation of pancreatic cysts.
View details for DOI 10.1186/1471-230X-12-15
View details for PubMedID 22333441
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In vivo near-infrared dual-axis confocal microendoscopy in the human lower gastrointestinal tract
JOURNAL OF BIOMEDICAL OPTICS
2012; 17 (2)
Abstract
Near-infrared confocal microendoscopy is a promising technique for deep in vivo imaging of tissues and can generate high-resolution cross-sectional images at the micron-scale. We demonstrate the use of a dual-axis confocal (DAC) near-infrared fluorescence microendoscope with a 5.5-mm outer diameter for obtaining clinical images of human colorectal mucosa. High-speed two-dimensional en face scanning was achieved through a microelectromechanical systems (MEMS) scanner while a micromotor was used for adjusting the axial focus. In vivo images of human patients are collected at 5 frames/sec with a field of view of 362×212 μm(2) and a maximum imaging depth of 140 μm. During routine endoscopy, indocyanine green (ICG) was topically applied a nonspecific optical contrasting agent to regions of the human colon. The DAC microendoscope was then used to obtain microanatomic images of the mucosa by detecting near-infrared fluorescence from ICG. These results suggest that DAC microendoscopy may have utility for visualizing the anatomical and, perhaps, functional changes associated with colorectal pathology for the early detection of colorectal cancer.
View details for DOI 10.1117/1.JBO.17.2.021102
View details for Web of Science ID 000303033600004
View details for PubMedID 22463020
View details for PubMedCentralID PMC3380818
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Colonoscopy With Clipping Is Useful in the Diagnosis and Treatment of Diverticular Bleeding
CLINICAL GASTROENTEROLOGY AND HEPATOLOGY
2012; 10 (2): 131-137
Abstract
Diverticular bleeding is the most common cause of acute severe lower gastrointestinal bleeding (LGIB) in Western countries. Diagnostic and therapeutic approaches, including endoscopy, radiology, or surgery, have not been standardized. We investigated colonoscopy as a first-line modality to diagnose and manage patients with LGIB.We performed a retrospective study of data collected from 2 tertiary Veterans hospitals of 64 patients (61 men, 76 ± 11 years) with acute severe diverticular bleeding, based on colonoscopy examination. We assessed primary hemostasis using endoscopic clipping for diverticular bleeding and described the bleeding stigmata. We measured early (<30 days) and late rebleeding, blood transfusion requirements, hospital stay and complications.Patients received 3.1 ± 3.0 and 0.9 ± 2.2 U of blood before and after colonoscopy, respectively. Twenty-four of the 64 patients (38%) had diverticular stigmata of recent hemorrhage; and 21 of these patients (88%) were treated successfully using endoscopic clips, without complication or early rebleeding. Hospital stays averaged 6.4 ± 5.6 days. Endoscopic clipping provided primary hemostasis in 9/12 patients (75%) with active diverticular bleeding. During 35 ± 18 months of follow-up, late recurrent diverticular bleeding occurred in 22% of the patients (14/64) after a mean time period of 22 months; 5 of the patients (21%) with stigmata of recent hemorrhage who received clip treatment had rebleeding at 43 months. Rebleeding was self-limited in 8 patients (57%), was clipped in 4 (29%), or was embolized in 2 (14%).Colonoscopy can be a safe first-line diagnostic and therapeutic approach for patients with severe LGIB. Endoscopic clipping provides hemostasis of active diverticular bleeding. Recurrent bleeding occurs in about 21% of patients who were treated with clips, at approximately 4 years; most bleeding is self-limited or can be retreated by endoscopic clipping.
View details for DOI 10.1016/j.cgh.2011.10.029
View details for Web of Science ID 000299789800015
View details for PubMedID 22056302
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Goff Trans-pancreatic Septotomy Is an Effective and Safe Biliary Cannulation Technique for Patients Who Fail Standard Biliary Cannulation
76th Annual Scientific Meeting of the American-College-of-Gastroenterology
NATURE PUBLISHING GROUP. 2011: S56–S56
View details for Web of Science ID 000299772000140
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Removal of infused water predominantly during insertion (water exchange) is consistently associated with a greater reduction of pain score - review of data in RCTs of water method colonoscopy
WILEY-BLACKWELL. 2011: 128–129
View details for Web of Science ID 000295099200346
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Safety and efficacy of colonoscopy to treat diverticular bleeding - long-term outcomes of a large multicenter cohort
WILEY-BLACKWELL. 2011: 79–79
View details for Web of Science ID 000295099200216
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Removal of Infused Water Predominantly During Insertion (Water Exchange) is Consistently Associated with a Higher Adenoma Detection Rate - Review of Data in Randomized Controlled Trials of Water Method Colonoscopy
76th Annual Scientific Meeting of the American-College-of-Gastroenterology
NATURE PUBLISHING GROUP. 2011: S566–S566
View details for Web of Science ID 000299772002322
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The water method significantly enhances patient-centered outcomes in sedated and unsedated colonoscopy
ENDOSCOPY
2011; 43 (9): 816-821
Abstract
Failure of cecal intubation when using air insufflation during scheduled unsedated colonoscopy in veterans prompted a literature search for a less uncomfortable approach. Water-related maneuvers as "adjuncts" to air insufflation were identified as effective in minimizing discomfort, although medication requirement was not reduced and willingness to repeat unsedated colonoscopy was not addressed. These adjunct maneuvers were combined with turning the air pump off to avoid colon elongation during insertion. Warm water infusion in lieu of air insufflation was evaluated in observational studies. Subsequent refinements evolved into the water method - a combination of air exclusion by aspiration of residual air to minimize angulations at flexures and a dynamic process of water exchange to remove feces in order to clear the view and aid insertion. In subsequent randomized controlled trials, the water method significantly reduced medication requirement, increased the proportion of patients in whom complete unsedated colonoscopy could be achieved, reduced patient recovery time burdens (sedation on demand), decreased abdominal discomfort during and after colonoscopy, enhanced cecal intubation, and increased willingness to repeat the procedure (scheduled unsedated). Supervised education of trainees and self-learning by an experienced colonoscopist were feasible. Lessons learned in developing the water method for optimizing patient-centered outcomes are presented. These proof-of-principle observations merit further research assessment in diverse settings.
View details for DOI 10.1055/s-0030-1256407
View details for Web of Science ID 000294543600011
View details for PubMedID 21611947
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Learning and teaching the water method (with videos).
Journal of interventional gastroenterology
2011; 1 (3): 127-129
Abstract
The water method is an insertion technique for colonoscopy which has recently become popular owing to its demonstrated ability to decrease patient pain and sedation requirements. This review focuses on learning and teaching the water method. Data from the United States and Asia suggests that trainees at all levels of experience can safely learn and utilize the water method. Demonstrated benefits in some of the reviewed studies include lessened sedation requirements, less pain for patients and increased cecal intubation rates in minimally sedated patients. These benefits are realized without compromising safety, adenoma detection rates, or procedure times.
View details for PubMedID 22163083
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Removal of infused water predominantly during insertion (water exchange) is consistently associated with an increase in adenoma detection rate - review of data in randomized controlled trials (RCTs) of water-related methods.
Journal of interventional gastroenterology
2011; 1 (3): 121-126
Abstract
INTRODUCTION: Variation in outcomes in RcTs comparing water-related methods and air insufflation raises challenging questions regarding the new approach. This report reviews impact of water exchange - simultaneous infusion and removal of infused water during insertion on adenoma detection rate (ADR) defined as proportion of patients with a least one adenoma of any size. METHODS: Medline (2008-2011) searches, abstract of 2011 Digestive Disease Week (DDW) meeting and personal communications were considered to identify RcTs that compared water-related methods and air insufflation to aid insertion of colonoscope. RESULTS: Since 2008, eleven reports of RcTs (6 published, 1 submitted and 4 abstracts, n=1728) described ADR in patients randomized to be examined by air and water-related methods. The water-related methods differed in timing of removal of the infused water -predominantly during insertion (water exchange) (n=825) or predominantly during withdrawal (water immersion) (n=903). Water immersion was associated with both increases and decreases in ADR compared to respective air method patients and the net overall change (-7%) was significant. On the other hand water exchange was associated with increases in ADR consistently and the net changes (overall, 8%; proximal overall, 11%; and proximal <10 mm, 12%) were all significant. CONCLUSION: Comparative data generated the hypothesis that significantly larger increases in overall and proximal colon ADRs were associated with water exchange than water immersion or air insufflation during insertion. The hypothesis should be evaluated by RCTs to elucidate the mechanism of water exchange on adenoma detection.
View details for PubMedID 22163082
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Removal of infused water predominantly during insertion (water exchange) is consistently associated with a greater reduction of pain score - review of randomized controlled trials (RCTs) of water method colonoscopy.
Journal of interventional gastroenterology
2011; 1 (3): 114-120
Abstract
INTRODUCTION: Variation in the outcomes in RcTs comparing water-related methods and air insufflation during the insertion phase of colonoscopy raises challenging questions regarding the approach. This report reviews the impact of water exchange on the variation in attenuation of pain during colonoscopy by water-related methods. METHODS: Medline (2008 to 2011) searches, abstracts of the 2011 Digestive Disease Week (DDW) and personal communications were considered to identify RcTs that compared water-related methods and air insufflation to aid insertion of the colonoscope. Results: Since 2008 nine published and one submitted RcTs and five abstracts of RcTs presented at the 2011 DDW have been identified. Thirteen RcTs (nine published, one submitted and one abstract, n=1850) described reduction of pain score during or after colonoscopy (eleven reported statistical significance); the remaining reports described lower doses of medication used, or lower proportion of patients experiencing severe pain in colonoscopy performed with water-related methods compared with air insufflation (Tables 1 and 2). The water-related methods notably differ in the timing of removal of the infused water - predominantly during insertion (water exchange) versus predominantly during withdrawal (water immersion). Use of water exchange was consistently associated with a greater attenuation of pain score in patients who did not receive full sedation (Table 3). CONCLUSION: The comparative data reveal that a greater attenuation of pain was associated with water exchange than water immersion during insertion. The intriguing results should be subjected to further evaluation by additional RcTs to elucidate the mechanism of the pain-alleviating impact of the water method.
View details for PubMedID 22163081
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A novel device for ablation of abnormal esophageal mucosa
GASTROINTESTINAL ENDOSCOPY
2011; 74 (1): 182-188
Abstract
Current ablation devices for Barrett's esophagus are effective but have significant limitations.To evaluate a new ablation device.Laboratory and animal model evaluation of the CryoBalloon, a compliant balloon that is simultaneously inflated and cooled by liquid nitrous oxide delivered by using a small, disposable, handheld unit.Cryoablation of esophageal mucosa was performed in 11 swine. Multiple ablations were created in each animal at various ablation times.Animals were euthanized at 4 days (n = 6) or 28 days (n = 5), and histological assessments were performed. At 4 days, the percentage of esophageal mucosa successfully ablated was measured. At 28 days, the circumference of the esophagus at the center of the ablation zone was measured to assess for stricture formation.The CryoBalloon was simple to operate, and balloon contact with tissue was easily maintained. As the ablation time was increased from 6 to 12 seconds, the percentage of mucosa ablated increased from below 60% to above 90%. Maximal effect on the mucosa was reached at 12 seconds. Ablation of up to 14 seconds resulted in minimal luminal narrowing. As the ablation duration increased from 14 to 22 seconds, there was progressive stricture formation evident at 28 days. All of the animals tolerated the treatments without difficulty and, regardless of ablation duration, were able to continue oral intake and gain weight after the procedure.Ablation of normal porcine squamous mucosa may differ from that of human Barrett's esophagus.The CryoBalloon device enables circumferential mucosal ablation in a 1-step process by using a novel, through-the-scope balloon. The maximal effect on the mucosa is achieved with a 12-second application time. Because of its ease of use, this new device merits further study so that we can find its possible role in the treatment of Barrett's esophagus.
View details for DOI 10.1016/j.gie.2011.03.1119
View details for Web of Science ID 000292429400027
View details for PubMedID 21531411
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Use of the Colonoscope Training Model with the Colonoscope 3D Imaging Probe Improved Trainee Colonoscopy Performance: A Pilot Study
DIGESTIVE DISEASES AND SCIENCES
2011; 56 (5): 1496-1502
Abstract
Colonoscopy insertion is difficult to teach due to the inability of current training models to provide realistic tactile sensation with simultaneous three-dimensional (3D) colonoscope display.To assess the influence of a simulator consisting of a colon model coupled with 3D instrument visualization on trainee colonoscopy performance.Pilot study using the simulator model with three trainees who were not proficient in colonoscopy. At random times over a 6-week period, trainees participated in an individualized half-day session using the Colonoscope Training Model and a colonoscope equipped with a 3D magnetic probe imaging system (ScopeGuide) in six standardized cases. A blinded supervising instructor graded patient-based colonoscopy performance over the 6-week period, and we independently analyzed the 2-week period before and after the intervention. We also measured cecal intubation and withdrawal times and medication requirements.Trainees performed 86 patient-based colonoscopies. Following the intervention, the colonoscopy performance score improved from 4.4 ± 2.3 to 5.9 ± 2.4 (p = 0.005). Trainees had a 76% cecal intubation rate following the session as compared to 43% before training (p = 0.004), while utilizing less time, 14 ± 7 versus 18 ± 11 min (p = 0.056) and less medication (p > 0.05).Colonoscopy simulation using the Colonoscope Training Model and the ScopeGuide produced an immediate and large effect on trainee colonoscopy performance.
View details for DOI 10.1007/s10620-011-1614-1
View details for Web of Science ID 000289899200033
View details for PubMedID 21409379
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DDW 2011 cutting edge colonoscopy techniques - state of the art lecture master class - warm water infusion/CO(2) insufflation for colonoscopy.
Journal of interventional gastroenterology
2011; 1 (2): 78-82
Abstract
Pain limits the success of cecal intubation in unsedated patient. Carbon dioxide infusion instead of air insufflation and water infusion as an adjunction to air insufflation have both been investigated as modalities to minimize pain associated with colonoscopy. Multiple RCT support an effect of carbon dioxide in reducing pain after colonoscopy. A modern method of water infusion as the sole modality for aiding colonoscope insertion has been shown to reduce pain during and after colonoscopy. Favorable effects in reducing discomfort have been documented in both sedated and unsedated patients. Because of the need to perform water exchange in the patients with suboptimal bowel perparation, a serendipitous consequence of salvage cleansing is evident with application of the water method. The associated increase in adenoma detection especially in the proximal colon is most intriguing. The hypothesis that the water method during insertion combined with carbon dioxide insufflation during withdrawal will optimally decrease colonoscopy pain should be evaluated. The implications of increased adenoma detection by the water method also deserve to be studied.
View details for PubMedID 21776430
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The water immersion technique for colonoscopy insertion.
Gastroenterology & hepatology
2010; 6 (9): 555-556
View details for PubMedID 21088743
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Integrating urgent multidetector CT scanning in the diagnostic algorithm of active lower GI bleeding
GASTROINTESTINAL ENDOSCOPY
2010; 72 (2): 402-405
View details for DOI 10.1016/j.gie.2010.04.014
View details for Web of Science ID 000280778800027
View details for PubMedID 20674629
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Water immersion versus standard colonoscopy insertion technique: randomized trial shows promise for minimal sedation
ENDOSCOPY
2010; 42 (7): 557-563
Abstract
Water immersion is an alternative colonoscopy technique that may reduce discomfort and facilitate insertion of the instrument. This was a prospective study to compare the success of colonoscopy with minimal sedation using water immersion and conventional air insufflation.A total of 229 patients were randomized to either water immersion or the standard air insertion technique. The primary outcome was success of minimal sedation colonoscopy, which was defined as reaching the cecum without additional sedation, exchange of the adult colonoscope or hands-on assistance for trainees. Patient comfort and satisfaction were also assessed.Successful minimal-sedation colonoscopy was achieved in 51 % of the water immersion group compared with 28 % in the standard air group (OR, 2.66; 95 % CI 1.48 - 4.79; P = 0.0004). Attending physicians had 79 % success with water immersion compared with 47 % with air insufflation (OR, 4.19; 95 % CI 1.5 - 12.17; P = 0.002), whereas trainees had 34 % success with water compared with 16 % using air (OR, 2.75; 95 % CI 1.15 - 6.86; P = 0.01). Using the water method, endoscopists intubated the cecum faster and this was particularly notable for trainees (13.0 +/- 7.5 minutes with water vs. 20.5 +/- 13.9 minutes with air; P = 0.0001). Total procedure time was significantly shorter with water for both experienced and trainee endoscopists ( P < 0.05). Patients reported less intraprocedural pain with water compared with air (4.1 +/- 2.7 vs. 5.3 +/- 2.7; P = 0.001), with a similar level of satisfaction. There was no difference in the neoplasm detection rates between the groups.Colonoscopy insertion using water immersion increases the success rate of minimal sedation colonoscopy. Use of the technique leads to a decrease in discomfort, time to reach the cecum, and the amount of sedative and analgesic used, without compromising patient satisfaction.
View details for DOI 10.1055/s-0029-1244231
View details for Web of Science ID 000279406900006
View details for PubMedID 20593332
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Long-Term Impact of Capsule Endoscopy in Patients Referred for Iron-Deficiency Anemia
DIGESTIVE DISEASES AND SCIENCES
2010; 55 (3): 703-708
Abstract
Video capsule endoscopy (VCE) is recommended as the third diagnostic test for patients with iron-deficiency anemia (IDA) after a normal upper endoscopy and colonoscopy.To study long-term outcomes after VCE in patients with IDA.We performed a retrospective study of VCE studies performed at Stanford University Hospital or the VA Palo Alto Health Care System from 2002 to 2006. We assessed endoscopic or radiographic procedures performed post-CE and contacted patients by telephone in order to determine current medical status and potential resolution of anemia since the VCE.We invited 153 patients to participate, and 82 (54%) patients agreed to enroll including 57 patients with IDA and 25 patients with overt gastrointestinal bleeding. The overt group received more transfusions pre-CE (P < 0.05). The mean follow-up time was 36 +/- 16 months (median 33 months, range 14-67) in the IDA referral group and 40 +/- 16 months (median 39 months, range 17-69) in the overt bleeding group (P = 0.3). Positive findings on VCE were detected in 35 (60%) and 15 (60%) patients in the IDA referral and overt groups, respectively (P= 1.0). Of the 35 patients in the IDA referral group with significant VCE findings, 15 underwent therapeutic procedures, while 20 were managed conservatively. Over the mean follow-up period, 23% of the IDA referral group and 22% of the overt group remained anemic (P = 0.30).Most patients referred for VCE examination to evaluate IDA were no longer anemic at 36 months of follow-up, with or without therapeutic intervention.
View details for DOI 10.1007/s10620-009-1046-3
View details for Web of Science ID 000274617500019
View details for PubMedID 19941072
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Meckel's Diverticulum with Gastrointestinal Bleeding: Role of Computed Tomography in Diagnosis
DIGESTIVE DISEASES AND SCIENCES
2010; 55 (2): 242-244
View details for DOI 10.1007/s10620-009-1029-4
View details for Web of Science ID 000273520900005
View details for PubMedID 19888654
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From Bench to Bedside with Advanced Confocal Microendoscope
IEEE Photonics Society Winter Topicals Meeting Series
IEEE. 2010: 83–84
View details for Web of Science ID 000283803700044
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Colonoscopy with Polypectomy in Patients Taking Clopidogrel.
Gastroenterology research
2009; 2 (4): 209-212
Abstract
To investigate the bleeding risk of colonoscopy with polypectomy in patients taking clopidogrel.Retrospective review of patients undergoing colonoscopy with polypectomy without interruption of clopidogrel. Patients with lesions larger than 1cm were generally rescheduled for polypectomy off clopidogrel. Most of the polyps were removed using cold snare technique. Endoscopic clips were routinely applied prophylactically.A total of 125 polypectomies were performed in 60 patients. The average polyp size was 5.4 ± 2.1 mm. One patient (1.7%, CI 0.3-8.9%) developed post-polypectomy bleeding that resolved without treatment. Three patients (5%, CI 1.7-14%) had immediate bleeding during the procedure and all resolved with prompt clip application.Polypectomy of lesions up to 1cm in size can be performed without interruption of clopidogrel.
View details for PubMedID 27942276
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Use of an endoscope-compatible probe to detect colonic dysplasia with Fourier transform infrared spectroscopy
JOURNAL OF BIOMEDICAL OPTICS
2009; 14 (4)
Abstract
Fourier transform infrared (FTIR) spectroscopy is sensitive to the molecular composition of tissue and has the potential to identify premalignant tissue (dysplasia) as an adjunct to endoscopy. We demonstrate collection of mid-infrared absorption spectra with a silver halide (AgCl(0.4)Br(0.6)) optical fiber and use spectral preprocessing to identify optimal subranges that classify colonic mucosa as normal, hyperplasia, or dysplasia. We collected spectra (n=83) in the 950 to 1800 cm(-1) regime on biopsy specimens obtained from human subjects (n=37). Subtle differences in the magnitude of the absorbance peaks at specific wave numbers were observed. The best double binary algorithm for distinguishing normal-versus-dysplasia and hyperplasia-versus-dysplasia was determined from an exhaustive search of spectral intervals and preprocessing techniques. Partial least squares discriminant analysis was used to classify the spectra using a leave-one-subject-out cross-validation strategy. The results were compared with histology reviewed independently by two gastrointestinal pathologists. The optimal thresholds identified resulted in an overall sensitivity, specificity, accuracy, and positive predictive value of 96%, 92%, 93%, and 82%, respectively. These results indicated that mid-infrared absorption spectra collected remotely with an optical fiber can be used to identify colonic dysplasia with high accuracy, suggesting that continued development of this technique for the early detection of cancer is promising.
View details for DOI 10.1117/1.3174387
View details for Web of Science ID 000270540100013
View details for PubMedID 19725718
View details for PubMedCentralID PMC3232016
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Endoscopic necrosectomy of organized pancreatic necrosis: a currently practiced NOTES procedure
JOURNAL OF HEPATO-BILIARY-PANCREATIC SURGERY
2009; 16 (3): 266-269
Abstract
Endoscopic necrosectomy is now an established minimally invasive method for treatment of organized pancreatic necrosis.Review of methods and results of endoscopic treatment of pancreatic necrosis.Reports by multiple groups have demonstrated favorable results of endoscopic necrosectomy. The mortality of critically ill patients undergoing endoscopic treatment in several series is approximately 10%. Some patients will eventually also require surgery for situations such as complete pancreatic duct disruption, but even in these cases endoscopic necrosectomy is useful because pancreatic surgery can often be delayed until the patient is stable.Endoscopic necrosectomy will likely assume an increasing role in the treatment of pancreatic necrosis. This should result in reduced morbidity and mortality in these critically ill patients.
View details for DOI 10.1007/s00534-009-0088-4
View details for Web of Science ID 000265566800005
View details for PubMedID 19350193
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Colonoscopic polypectomy in anticoagulated patients
WORLD JOURNAL OF GASTROENTEROLOGY
2009; 15 (16): 1973-1976
Abstract
To review our experience performing polypectomy in anticoagulated patients without interruption of anticoagulation.Retrospective chart review at the Veterans Affairs Palo Alto Health Care System. Two hundred and twenty five polypectomies were performed in 123 patients. Patients followed a standardized protocol that included stopping warfarin for 36 h to avoid supratherapeutic anticoagulation from the bowel preparation. Patients with lesions larger than 1 cm were generally rescheduled for polypectomy off warfarin. Endoscopic clips were routinely applied prophylactically.One patient (0.8%, 95% CI: 0.1%-4.5%) developed major post-polypectomy bleeding that required transfusion. Two others (1.6%, 95% CI: 0.5%-5.7%) had self-limited hematochezia at home and did not seek medical attention. The average polyp size was 5.1 +/- 2.2 mm.Polypectomy can be performed in therapeutically anticoagulated patients with lesions up to 1 cm in size with an acceptable bleeding rate.
View details for DOI 10.3748/wjg.15.1973
View details for Web of Science ID 000265619800008
View details for PubMedID 19399929
View details for PubMedCentralID PMC2675087
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Safe endoscopic treatment of large colonic lipomas using endoscopic looping technique
DIGESTIVE AND LIVER DISEASE
2008; 40 (12): 958-961
Abstract
Colonic lipomas are benign, submucosal tumours that are usually asymptomatic. Typically, they are incidentally diagnosed during colonoscopy. Due to a low prevalence, the natural history of lipomas remains largely unknown. While large (>2 cm) lesions can cause symptoms and complications, their endoscopic treatment is not routinely recommended because of prior reports of a high rate of perforation.We used a standardized technique of polypectomy, using endoscopic looping to resect large colonic lipomas in 8 patients and followed their clinical outcomes.The mean lipoma size was 3.8+/-1.2 cm (range 2.5-6 cm). No patient developed bleeding or perforation. On follow-up (mean=13.5 months, range 2-29), there was one small residual lesion.Colonic lipomas larger than 2 cm can be safely and efficaciously removed using endoloop assisted polypectomy technique.
View details for DOI 10.1016/j.dld.2008.03.010
View details for Web of Science ID 000261804600008
View details for PubMedID 18434264
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A randomised tandem colonoscopy trial of narrow band imaging versus white light examination to compare neoplasia miss rates
GUT
2008; 57 (10): 1406-1412
Abstract
Colonoscopy, the "gold standard" screening test for colorectal cancer (CRC), has known diagnostic limitations. Advances in endoscope technology have focused on improving mucosal visualisation. In addition to increased angle of view and resolution features, recent colonoscopes have non-white-light optics, such as narrow band imaging (NBI), to enhance image contrast. We aimed to study the neoplasia diagnostic characteristics of NBI, by comparing the neoplasm miss rate when the colonoscopy was performed under NBI versus white light (WL).Randomised controlled trial.US Veterans hospital.Elective colonoscopy adults.We randomly assigned patients to undergo a colonoscopic examination using NBI or WL. All patients underwent a second examination using WL, as the reference standard.The primary end point was the difference in the neoplasm miss rate, and secondary outcome was the neoplasm detection rate.In 276 tandem colonoscopy patients, there was no significant difference of miss or detection rates between NBI or WL colonoscopy techniques. Of the 135 patients in the NBI group, 17 patients (12.6%; 95% confidence interval (CI) 7.5 to 19.4%) had a missed neoplasm, as compared with 17 of the 141 patients (12.1%; 95% CI 7.2 to 18.6%) in the WL group, with a miss rate risk difference of 0.5% (95% CI -7.2 to 8.3). 130 patients (47%) had at least one neoplasm. Missed lesions with NBI showed similar characteristics to those missed with WL. All missed neoplasms were tubular adenomas, the majority (78%) was < or = 5 mm and none were larger than 1 cm (one-sided 95% CI up to 1%). Nonpolypoid lesions represented 35% (13/37) of missed neoplasms.NBI did not improve the colorectal neoplasm miss rate compared to WL; the miss rate for advanced adenomas was less than 1% and for all adenomas was 12%. The neoplasm detection rates were similar high using NBI or WL; almost a half the study patients had at least one adenoma. Clinicaltrials.gov identifier: NCT00628147.
View details for DOI 10.1136/gut.2007.137984
View details for Web of Science ID 000259198800017
View details for PubMedID 18523025
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Integrated gastrointestinal imaging and therapy
GASTROENTEROLOGY
2008; 134 (5): 1290-1292
View details for DOI 10.1053/j.gastro.2008.03.047
View details for Web of Science ID 000255676700008
View details for PubMedID 18471503
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Detection of colonic dysplasia in vivo using a targeted heptapeptide and confocal microendoscopy
NATURE MEDICINE
2008; 14 (4): 454-458
Abstract
A combination of targeted probes and new imaging technologies provides a powerful set of tools with the potential to improve the early detection of cancer. To develop a probe for detecting colon cancer, we screened phage display peptide libraries against fresh human colonic adenomas for high-affinity ligands with preferential binding to premalignant tissue. We identified a specific heptapeptide sequence, VRPMPLQ, which we synthesized, conjugated with fluorescein and tested in patients undergoing colonoscopy. We imaged topically administered peptide using a fluorescence confocal microendoscope delivered through the instrument channel of a standard colonoscope. In vivo images were acquired at 12 frames per second with 50-microm working distance and 2.5-microm (transverse) and 20-microm (axial) resolution. The fluorescein-conjugated peptide bound more strongly to dysplastic colonocytes than to adjacent normal cells with 81% sensitivity and 82% specificity. This methodology represents a promising diagnostic imaging approach for the early detection of colorectal cancer and potentially of other epithelial malignancies.
View details for DOI 10.1038/nm1692
View details for Web of Science ID 000254674100034
View details for PubMedID 18345013
View details for PubMedCentralID PMC3324975
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Prevalence of nonpolypoid (flat and depressed) colorectal neoplasms in asymptomatic and symptomatic adults
JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION
2008; 299 (9): 1027-1035
Abstract
Colorectal cancer is the second leading cause of cancer death in the United States. Prevention has focused on the detection and removal of polypoid neoplasms. Data are limited on the significance of nonpolypoid colorectal neoplasms (NP-CRNs).To determine the prevalence of NP-CRNs in a veterans hospital population and to characterize their association with colorectal cancer.Cross-sectional study at a veterans hospital in California with 1819 patients undergoing elective colonoscopy from July 2003 to June 2004.Endoscopic appearance, location, size, histology, and depth of invasion of neoplasms.The overall prevalence of NP-CRNs was 9.35% (95% confidence interval [95% CI], 8.05%-10.78%; n = 170). The prevalence of NP-CRNs in the subpopulations for screening, surveillance, and symptoms was 5.84% (95% CI, 4.13%-8.00%; n = 36), 15.44% (95% CI, 12.76%-18.44%; n = 101), and 6.01% (95% CI, 4.17%-8.34%; n = 33), respectively. The overall prevalence of NP-CRNs with in situ or submucosal invasive carcinoma was 0.82% (95% CI, 0.46%-1.36%; n = 15); in the screening population, the prevalence was 0.32% (95% CI, 0.04%-1.17%; n = 2). Overall, NP-CRNs were more likely to contain carcinoma (odds ratio, 9.78; 95% CI, 3.93-24.4) than polypoid lesions, irrespective of the size. The positive size-adjusted association of NP-CRNs with in situ or submucosal invasive carcinoma was also observed in subpopulations for screening (odds ratio, 2.01; 95% CI, 0.27-15.3) and surveillance (odds ratio, 63.7; 95% CI, 9.41-431). The depressed type had the highest risk (33%). Nonpolypoid colorectal neoplasms containing carcinoma were smaller in diameter as compared with the polypoid ones (mean [SD] diameter, 15.9 [10.2] mm vs 19.2 [9.6] mm, respectively). The procedure times did not change appreciably as compared with historical controls.In this group of veteran patients, NP-CRNs were relatively common lesions diagnosed during routine colonoscopy and had a greater association with carcinoma compared with polypoid neoplasms, irrespective of size.
View details for Web of Science ID 000253644800020
View details for PubMedID 18319413
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American gastroenterological association (AGA) institute technology assessment on image-enhanced endoscopy
GASTROENTEROLOGY
2008; 134 (1): 327-340
Abstract
This document presents the official recommendations of the American Gastroenterological Association (AGA) Institute Technology Assessment on "Image-Enhanced Endoscopy." It was approved by the Clinical Practice and Economics Committee on August 3, 2007, and by the AGA Institute Governing Board September 27, 2007.
View details for DOI 10.1053/j.gastro.2007.10.062
View details for Web of Science ID 000252066400037
View details for PubMedID 18061178
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Small caliber overtube-assisted colonoscopy
WORLD JOURNAL OF GASTROENTEROLOGY
2007; 13 (44): 5933-5937
Abstract
To combine the benefits of a new thin flexible scope with elimination of excessive looping through the use of an overtube.Three separate retrospective series. Series 1: 25 consecutive male patients undergoing unsedated colonoscopy using the new device at a Veteran's hospital in the United States. Series 2: 75 male patients undergoing routine colonoscopy using an adult colonoscope, pediatric colonoscope, or the new device. Series 3: 35 patients who had incomplete colonoscopies using standard instruments.Complete colonoscopy was achieved in all 25 patients in the unsedated series with a median cecal intubation time of 6 min and a median maximal pain score of 3 on a 0-10 scale. In the 75 routine cases, there was significantly less pain with the thin scope compared to standard adult and pediatric colonoscopes. Of the 35 patients in the previously incomplete colonoscopy series, 33 were completed with the new system.Small caliber overtube-assisted colonoscopy is less painful than colonoscopy with standard adult and pediatric colonoscopes. Male patients could undergo unsedated colonoscopy with the new system with relatively little pain. The new device is also useful for most patients in whom colonoscopy cannot be completed with standard instruments.
View details for Web of Science ID 000250799800015
View details for PubMedID 17990359
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Functional imaging of colonic mucosa with a fibered Confocal microscope for real-time in vivo pathology
CLINICAL GASTROENTEROLOGY AND HEPATOLOGY
2007; 5 (11): 1300-1305
Abstract
Histologic interpretation of disease currently is performed with static images of excised tissues, and is limited by processing artifact, sampling error, and interpretive variability. The aim of this study was to show the use of functional optical imaging of viable mucosa for quantitative evaluation of colonic neoplasia in real time.Fluorescein (5 mg/mL) was administered topically in 54 human subjects undergoing screening colonoscopy. Fluorescence images were collected with 488-nm excitation at 12 frames/s with the confocal microendoscopy system. Movement of fluorescein in the transient period (<5 s) and the lamina propria:crypt contrast ratio in the steady-state phase (>5 s) were quantified.Normal mucosa showed circular crypts with uniform size, hyperplasia revealed proliferative glands with serrated lumens, and adenomas displayed distorted elongated glands. For t less than 5 seconds, fluorescein passed through normal epithelium with a peak speed of 1.14 +/- 0.09 microm/s at t = 0.5 seconds, and accumulated into lamina propria as points of fluorescence that moved through the interglandular space with an average speed of 41.7 +/- 3.4 microm/s. Passage of fluorescein through adenomatous mucosa was delayed substantially. For t greater than 5 seconds, high sensitivity, specificity, and accuracy was achieved using a discriminant function to evaluate the contrast ratio to distinguish normal from lesional mucosa (91%, 87%, and 89%, respectively; P < .001), hyperplasia from adenoma (97%, 96%, and 96%, respectively; P < .001), and tubular from villous adenoma (100%, 92%, and 93%, respectively; P < .001).Confocal imaging can be performed in vivo to assess the functional behavior of tissue in real time for providing pathologic interpretation, representing a new method for histologic evaluation.
View details for DOI 10.1016/j.cgh.2007.07.013
View details for Web of Science ID 000250944900012
View details for PubMedID 17936692
View details for PubMedCentralID PMC2104519
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Detection of endogenous biomolecules in Barrett's esophagus by Fourier transform infrared spectroscopy
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2007; 104 (40): 15864-15869
Abstract
Fourier transform infrared (FTIR) spectroscopy provides a unique molecular fingerprint of tissue from endogenous sources of light absorption; however, specific molecular components of the overall FTIR signature of precancer have not been characterized. In attenuated total reflectance mode, infrared light penetrates only a few microns of the tissue surface, and the influence of water on the spectra can be minimized, allowing for the analyses of the molecular composition of tissues. Here, spectra were collected from 98 excised specimens of the distal esophagus, including 38 squamous, 38 intestinal metaplasia (Barrett's), and 22 gastric, obtained endoscopically from 32 patients. We show that DNA, protein, glycogen, and glycoprotein comprise the principal sources of infrared absorption in the 950- to 1,800-cm(-1) regime. The concentrations of these biomolecules can be quantified by using a partial least-squares fit and used to classify disease states with high sensitivity, specificity, and accuracy. Moreover, use of FTIR to detect premalignant (dysplastic) mucosa results in a sensitivity, specificity, positive predictive value, and total accuracy of 92%, 80%, 92%, and 89%, respectively, and leads to a better interobserver agreement between two gastrointestinal pathologists for dysplasia (kappa = 0.72) versus histology alone (kappa = 0.52). Here, we demonstrate that the concentration of specific biomolecules can be determined from the FTIR spectra collected in attenuated total reflectance mode and can be used for predicting the underlying histopathology, which will contribute to the early detection and rapid staging of many diseases.
View details for DOI 10.1073/pnas.0707567104
View details for Web of Science ID 000249942700049
View details for PubMedID 17901200
View details for PubMedCentralID PMC2000401
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Long-term use of proton pump inhibitors does not affect the frequency, growth, or histologic characteristics of colon adenomas
ALIMENTARY PHARMACOLOGY & THERAPEUTICS
2007; 26 (7): 1051-1061
Abstract
The clinical significance of the trophic effects of long-term proton pump inhibitors (PPI)-related hypergastrinemia on colon polyps remains unknown.To study the frequency, growth, and histology of colon polyps in patients on chronic PPI therapy (cases), compared to those not receiving acid suppression (controls).Medical records of 2868 consecutive patients who underwent two or more colonoscopies, performed 3 or more months apart were reviewed. Cases (116) that used PPIs between the two colonoscopies were then compared to controls (194).Demographics and risk factors for colon cancer were comparable between the two groups. At baseline the mean frequency and size of adenomatous polyps were similar in cases and controls (P > 0.05) and at follow-up, these were 0.89 and 1.18 (P > 0.05; 95% CI of -0.08 to 0.66) and 4.09 mm and 4.00 mm (P > 0.05; 95% CI -2.29 to 2.11), respectively with no significant change. However, control group had a higher mean frequency and size of hyperplastic polyps at baseline as well as at follow-up colonoscopy (P < 0.05).The long-term use of PPI does not influence the frequency, growth, or histology of adenomatous polyps, but is associated with a reduction in both baseline and interval development of hyperplastic polyps.
View details for DOI 10.1111/j.1365-2036.2007.03450.x
View details for Web of Science ID 000249482000009
View details for PubMedID 17877512
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Short- and long-term outcomes of standardized EMR of nonpolypoid (flat and depressed) colorectal lesions >= 1 cm (with video)
GASTROINTESTINAL ENDOSCOPY
2007; 65 (6): 857-865
Abstract
Nonpolypoid (flat and depressed) colorectal lesions are increasingly recognized. Their endoscopic removal requires specialized EMR techniques, which are more complex to perform. Outcomes data on EMR of nonpolypoid neoplasms in the United States is needed.To determine the safety and efficacy of EMR in the resection of nonpolypoid colorectal neoplasms > or = 1 cm.Retrospective analysis.Veterans Affairs Palo Alto Health Care System.Over a 5-year period, patients who underwent EMR for nonpolypoid colorectal lesions > or = 1 cm.A standardized approach that included lesion assessment, classification, inject-and-cut EMR technique, reassessment, and treatment of residual tissue.Complete resection, bleeding, perforation, development of advanced cancer, and death.A total of 100 patients (125 lesions: 117 flat and 8 depressed) met inclusion criteria. Mean size was 16.7 +/- 7 mm (range, 10-50 mm). Histology included 5 submucosal invasive cancers, 5 carcinomas in situ, and 91 adenomas. Thirty-eight patients (48 lesions) did not receive surveillance colonoscopy: 8 had surgery, 16 had hyperplastic pathology, and 14 did not undergo repeat examination. Surveillance colonoscopy was performed on 62 patients (77 lesions). Complete resection was achieved in 100% of these patients after 1 to 3 surveillance colonoscopies. All patients received follow-up (mean [standard deviation] = 4.5 +/- 1.4 years); none developed colorectal cancer or metastasis.Single endoscopist, retrospective study.A standardized EMR (inject-and-cut) technique is a safe and curative treatment option in nonpolypoid colorectal neoplasms (> or = 1 cm) in the United States.
View details for DOI 10.1016/j.gie.2006.11.035
View details for PubMedID 17466205
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Transnasal small-caliber esophagogastroduodenoscopy for preoperative evaluation of the high-risk morbidly obese patient
SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES
2007; 21 (5): 758-760
Abstract
Esophagogastroduodenoscopy (EGD) is an important facet of the preoperative evaluation for bariatric surgery. Morbidly obese patients are at high risk for airway complications during this procedure, and an attractive alternative is transnasal EGD. This report describes a series of patients evaluated successfully using this technique.All patients undergoing preoperative transnasal small-caliber EGD for morbid obesity surgery between September 2004 and June 2005 at a Veterans Affairs Hospital were included in the analysis. The variables assessed were the adequacy of the examination, patient tolerance, the need for sedation, and the ability to perform interventions.The study enrolled 25 patients (17 men and 8 women) with an average age of 55 years (range, 44-63 years) and an average body mass index (BMI) of 47 kg/m2 (range, 38-69 kg/m2). All the patients met the 1991 National Institutes of Health (NIH) Consensus Conference Criteria for bariatric surgery and were undergoing preoperative evaluation. The most common comorbidities were hypertension (82%), diabetes mellitus (80%), and obstructive sleep apnea (68%). All 25 patients had successful cannulation of the duodenum's second portion with excellent tolerance. There were no sedation requirements for 23 (92%) of the 25 patients. Significant pathology was found in 14 (56%) of the 25 patients, including hiatal hernia (28%), gastritis (16%), esophageal intestinal metaplasia (16%), esophagitis (12%), gastric polyps (8%), gastric ulcer (4%) and esophageal varices (4%). Biopsies were indicated for 12 patients and successful for all 12 (100%).Transnasal small-caliber EGD is a feasible and safe alternative to conventional EGD for the preoperative evaluation of patients undergoing bariatric surgery. It requires minimal to no sedation in a population at high risk for complications in this setting. In addition, this technique is effective in identifying pathology that requires preoperative treatment and offers a complete examination with biopsy capabilities. This technique should be considered for all morbidly obese patients at high risk for airway compromise during EGD.
View details for DOI 10.1007/s00464-006-9101-z
View details for Web of Science ID 000246351800013
View details for PubMedID 17235723
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Diagnosis of chronic mesenteric ischemia by visible light spectroscopy during endoscopy
GASTROINTESTINAL ENDOSCOPY
2007; 65 (2): 294-300
Abstract
Chronic mesenteric ischemia can be difficult to diagnose by means of currently available clinical techniques. We developed a novel endoscopic device for objective measurement of GI mucosal ischemia.Our purpose was to evaluate the performance of the device in patients with chronic mesenteric ischemia.A fiberoptic catheter-based visible light spectroscopy oximeter (T-Stat 303 Microvascular Oximeter, Spectros, Portola Valley, Calif) was used to evaluate 30 healthy control subjects and 3 patients with chronic mesenteric ischemia before and after successful percutaneous stenting.Veterans Affairs Palo Alto Health Care System hospital.Normal mucosal (capillary) hemoglobin oxygen saturation was 60% to 73% in the duodenum and jejunum. In the 3 patients with chronic mesenteric ischemia, ischemic areas in the duodenum or proximal jejunum were found with mucosal saturations of 16% to 30%. After successful angioplasty and stent placement of the celiac, superior mesenteric, or inferior mesenteric arteries, the mucosal saturation in these areas increased to 51% to 60%.This preliminary study suggests that chronic mesenteric ischemia is detectable during endoscopy by use of visible light spectroscopy and that successful endovascular treatment results in near normalization of mucosal oxygen saturation.
View details for DOI 10.1016/j.gie.2006.05.007
View details for Web of Science ID 000244041900023
View details for PubMedID 17137857
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Prophylactic clip application after colonic polypectomy - Response
GASTROINTESTINAL ENDOSCOPY
2007; 65 (1): 183
View details for DOI 10.1016/j.gie.2006.08.013
View details for Web of Science ID 000243361000056
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Use of a double balloon enteroscope facilitates caecal intubation after incomplete colonoscopy with a standard colonoscope
DIGESTIVE AND LIVER DISEASE
2006; 38 (12): 921-925
Abstract
Caecal intubation is a necessary step in the complete endoscopic evaluation of the colon. Studies have estimated that experienced colonoscopists may fail to reach the caecum in up to 10% of cases.To evaluate the utility of the double balloon enteroscope used for complete examination of the colon in patients with incomplete standard colonoscopy.Twenty consecutive patients with incomplete colonoscopies within the Veterans Affairs Palo Alto Health Care System. Mean age of 66 years (S.D.+/-12 years, range 46-84), 16 men.Prospective single-centre case series on the caecal intubation rate using standard double balloon enteroscope technique in patients with previous incomplete conventional colonoscopy.Use of the standard double balloon enteroscope technique permitted complete colonoscopy to be achieved in 95% of the patients (19/20). Seven patients (35%) had significant pathology beyond the extent of the prior incomplete colonoscopy. We performed endoscopic mucosal resection, polypectomy or biopsy. The mean time to reach the caecum was 28 min (S.D.+/-20 min, range 6-90 min). The sedation was similar to conventional colonoscopy. No complications occurred.The double balloon enteroscope technology and technique can be used to complete examination of the colon in patients who were referred because of incomplete standard colonoscopy.
View details for DOI 10.1016/j.dld.2006.08.003
View details for Web of Science ID 000243715600010
View details for PubMedID 16990055
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Dual-axes confocal reflectance microscope for distinguishing colonic neoplasia
JOURNAL OF BIOMEDICAL OPTICS
2006; 11 (5)
Abstract
A dual-axes confocal reflectance microscope has been developed that utilizes a narrowband laser at 1310 nm to achieve high axial resolution, image contrast, field of view, and tissue penetration for distinguishing among normal, hyperplastic, and dysplastic colonic mucosa ex vivo. Light is collected off-axis using a low numerical aperture objective to obtain vertical image sections, with 4- to 5-microm resolution, at tissue depths up to 610 microm. Post-objective scanning enables a large field of view (610 x 640 microm), and balanced-heterodyne detection provides sensitivity to collect vertical sections at one frame per second. System optics are optimized to effectively reject out-of-focus scattered light without use of a low-coherence gate. This design is scalable to millimeter dimensions, and the results demonstrate the potential for a miniature instrument to detect precancerous tissues, and hence to perform in vivo histopathology.
View details for DOI 10.1117/1.2363363
View details for Web of Science ID 000242576900023
View details for PubMedID 17092168
View details for PubMedCentralID PMC2104521
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Long-term proton pump inhibitors (PPIs) use does not affect the frequency, growth, or histologic characteristics of colon polyps
71st Annual Scientific Meeting of the American-College-of-Gasroenterology
NATURE PUBLISHING GROUP. 2006: S215–S215
View details for Web of Science ID 000240656101001
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Colonoscopy with polypectomy in anticoagulated patients
GASTROINTESTINAL ENDOSCOPY
2006; 64 (1): 98-100
Abstract
According to current practice guidelines for performance of colonoscopy in patients requiring long-term anticoagulation, polypectomy is considered a high-risk procedure for which anticoagulation must temporarily be discontinued. However, these guidelines are based on expert opinion, and the bleeding risk after polypectomy in anticoagulated patients is not known.Measure the risk of postpolypectomy bleeding in patients who undergo colonoscopic polypectomy while anticoagulated.Retrospective review of patients who underwent polypectomy without discontinuation of anticoagulation.Veterans Administration Palo Alto Health Care System.Forty-one polypectomies were performed in 21 patients. All patients had been receiving long-term anticoagulation with warfarin; the average international normalized ratio was 2.3 (range 1.4-4.9; normal 0.9-1.2). To prevent supratherapeutic anticoagulation, warfarin was withheld for 36 hours before the procedure while the patients were on a liquid diet. The average polyp size was 5 mm (range 3-10 mm).All patients underwent polypectomy followed immediately by prophylactic application of one or two clips to prevent bleeding.Rate of postpolypectomy bleeding.There were no episodes of postpolypectomy bleeding. The 95% CI for the risk of bleeding was 0% to 8.6% when analyzed per polypectomy and 0% to 15% when analyzed per patient.Small single-center retrospective study.Our experience suggests that small polyps can be removed with a very low risk of bleeding when clips are applied immediately after polypectomy. If these results can be confirmed in a larger multicenter study, our protocol may become an alternative to withholding anticoagulation in patients at high risk of thrombosis.
View details for DOI 10.1016/j.gie.2006.02.030
View details for Web of Science ID 000238766600019
View details for PubMedID 16813811
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Absence of ischemia in telangiectasias of chronic radiation proctopathy
ENDOSCOPY
2006; 38 (5): 488-492
Abstract
It has been postulated that chronic radiation proctopathy, clinically manifested by hematochezia and by the appearance of multiple telangiectasias, is caused by ischemia. This theory is based on reports that appeared in the 1980s which described obliterative endarteritis in patients with chronic radiation-induced ulcers. However, bleeding from radiation proctopathy is typically successfully treated endoscopically by widespread tissue coagulation, and the complications that would be expected to occur if the tissue was ischemic, such as poor wound healing, generally do not arise. We therefore hypothesized that the ischemia theory is incorrect and that rectal capillary oxygen saturation is normal in patients with telangiectasias of chronic radiation proctopathy.We developed a visible-light spectroscopy device that measures mucosal capillary hemoglobin oxygen saturation during endoscopy (having reported its operating characteristics previously). We prospectively studied 20 patients who had typical findings of multiple rectal telangiectasias, 1 - 20 years after undergoing external-beam irradiation for prostate or rectal carcinoma. We measured and compared the mucosal capillary oxygen saturations in the affected areas of the distal rectum and in endoscopically normal areas in the rectosigmoid colon.Mucosal oxygenation was normal in all 20 patients in affected areas (64 % - 80 %) and in unaffected areas (63 % - 75 %). The mean mucosal hemoglobin oxygen saturation was actually slightly higher in the affected areas of the rectum than in the uninvolved rectosigmoid colon (73 % vs. 69 %, P < 0.01).The common form of chronic radiation proctopathy, characterized by multiple telangiectasias without ulcers or strictures, is not associated with ongoing mucosal ischemia. This finding may explain why endoscopic treatment of this disorder, in which large areas of the mucosa are coagulated with argon plasma or other treatment modalities that cause widespread ulceration, does not typically result in complications from poor wound healing.
View details for DOI 10.1055/s-2005-921175
View details for Web of Science ID 000237922000009
View details for PubMedID 16767584
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Clipping for upper gastrointestinal bleeding
AMERICAN JOURNAL OF GASTROENTEROLOGY
2006; 101 (5): 915-918
View details for DOI 10.1111/j.1572-0241.2005.00371.x
View details for Web of Science ID 000237463300001
View details for PubMedID 16696776
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Colonic Mucosal Resection of Significant (> 1 cm) Sessile and Non-Polypoid Colorectal Neoplasms: Long Term Experience of a United States Endoscopy Unit. Tonya Kaltenbach, Anamika Maheshwari, Daniel Ouyang, Shai Friedland, Roy Soetikno Division of Gastroenterology, Veterans Affairs Palo Alto Health Care System, Stanford University School of Medicine, Stanford CA
MOSBY-ELSEVIER. 2006: AB203–AB203
View details for Web of Science ID 000207499900464
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Nonpolypoid (flat and depressed) colorectal neoplasms
GASTROENTEROLOGY
2006; 130 (2): 566-576
View details for DOI 10.1053/j.gastro.2005.12.006
View details for Web of Science ID 000235525700029
View details for PubMedID 16472608
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A learning curve for advanced endoscopic resection
GASTROINTESTINAL ENDOSCOPY
2005; 62 (6): 866-867
View details for DOI 10.1016/j.gie.2005.07.055
View details for Web of Science ID 000233699800008
View details for PubMedID 16301027
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Design of a visible-light spectroscopy clinical tissue oximeter
JOURNAL OF BIOMEDICAL OPTICS
2005; 10 (4)
Abstract
We develop a clinical visible-light spectroscopy (VLS) tissue oximeter. Unlike currently approved near-infrared spectroscopy (NIRS) or pulse oximetry (SpO2%), VLS relies on locally absorbed, shallow-penetrating visible light (475 to 625 nm) for the monitoring of microvascular hemoglobin oxygen saturation (StO2%), allowing incorporation into therapeutic catheters and probes. A range of probes is developed, including noncontact wands, invasive catheters, and penetrating needles with injection ports. Data are collected from: 1. probes, standards, and reference solutions to optimize each component; 2. ex vivo hemoglobin solutions analyzed for StO2% and pO2 during deoxygenation; and 3. human subject skin and mucosal tissue surfaces. Results show that differential VLS allows extraction of features and minimization of scattering effects, in vitro VLS oximetry reproduces the expected sigmoid hemoglobin binding curve, and in vivo VLS spectroscopy of human tissue allows for real-time monitoring (e.g., gastrointestinal mucosal saturation 69+/-4%, n=804; gastrointestinal tumor saturation 45+/-23%, n=14; and p<0.0001), with reproducible values and small standard deviations (SDs) in normal tissues. FDA approved VLS systems began shipping earlier this year. We conclude that VLS is suitable for the real-time collection of spectroscopic and oximetric data from human tissues, and that a VLS oximeter has application to the monitoring of localized subsurface hemoglobin oxygen saturation in the microvascular tissue spaces of human subjects.
View details for DOI 10.1117/1.1979504
View details for Web of Science ID 000232799200015
View details for PubMedID 16178639
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Optical detection of tumors in vivo by visible light tissue oximetry
TECHNOLOGY IN CANCER RESEARCH & TREATMENT
2005; 4 (3): 227-234
Abstract
Endoscopy is a standard procedure for identifying tumors in patients suspected of having gastrointestinal (G.I.) cancer. The early detection of G.I. neoplasms during endoscopy is currently made by a subjective visual inspection that relies to a high degree on the experience of the examiner. This process can be difficult and unreliable, as tumor lesions may be visually indistinguishable from benign inflammatory conditions and the surrounding mucosa. In this study, we evaluated the ability of local ischemia detection using visible light spectroscopy (VLS) to differentiate neoplastic from normal tissue based on capillary tissue oxygenation during endoscopy. Real-time data were collected (i) from human subjects (N = 34) monitored at various sites during endoscopy (enteric mucosa, malignant, and abnormal tissue such as polyps) and (ii) murine animal subjects with human tumor xenografts. Tissue oximetry in human subjects during endoscopy revealed a tissue oxygenation (StO2%, mean +/- SD) of 46 +/- 22% in tumors, which was significantly lower than for normal mucosal oxygenation (72 +/- 4%; P < or = 0.0001). No difference in tissue oxygenation was observed between normal and non-tumor abnormal tissues (P = N.S.). Similarly, VLS tissue oximetry for murine tumors revealed a mean local tumor oxygenation of 45% in LNCaP, 50% in M21, and 24% in SCCVII tumors, all significantly lower than normal muscle tissue (74%, P < 0.001). These results were further substantiated by positive controls, where a rapid real-time drop in tumor oxygenation was measured during local ischemia induced by clamping or epinephrine. We conclude that VLS tissue oximetry can distinguish neoplastic tissue from normal tissue with a high specificity (though a low sensitivity), potentially aiding the endoscopic detection of gastrointestinal tumors.
View details for Web of Science ID 000229787600001
View details for PubMedID 15896077
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18-fluorodeoxyglucose positron emission tomography has limited sensitivity for colonic adenoma and early stage colon cancer
Digestive Disease Week Meeting/105th Annual Meeting of the American-Gastroenterological-Association
MOSBY-ELSEVIER. 2005: 395–400
Abstract
18-Fluorodeoxyglucose positron emission tomography (PET) is used clinically to detect recurrent colon cancer after surgical resection, but the sensitivity of PET for premalignant colon lesions and early stage colon cancer is not well defined.In a prospective study, 45 patients with a total of 58 colonic neoplasms, including premalignant polyps, premalignant, flat lesions, and early stage cancers, were evaluated by PET.The sensitivity of PET for cancer was 62% (8/13). PET detected 100% (7/7) of cancers 2 cm or larger but only 17% (1/6) of cancers smaller than 2 cm. PET detected 23% (3/13) of flat, premalignant lesions; 70% (7/10) of protruded, premalignant lesions 3 cm or larger; 38% (3/8) of protruded, premalignant lesions between 2 and 2.9 cm; and 14% (2/14) of protruded, premalignant lesions between 1 and 1.9 cm. There was no false-positive PET reading.PET has limited sensitivity for flat, premalignant lesions; protruded, premalignant lesions smaller than 3 cm; and colon cancers smaller than 2 cm.
View details for Web of Science ID 000227861300008
View details for PubMedID 15758910
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Reflectance spectrophotometry for the assessment of mucosal perfusion in the gastrointestinal tract.
Gastrointestinal endoscopy clinics of North America
2004; 14 (3): 539-?
Abstract
Reflectance spectrophotometry (RS) is an optical technology that has been used for nearly three decades in the measurement of tissue hemoglobin oxygen saturation in the gastrointestinal tract. The technology has evolved substantially throughout this period,and commercial devices are now available for use in clinical trials. Numerous studies have used RS to investigate the importance of mucosal perfusion in disorders such as ulcer disease, portal hypertension, and septic shock. More recently, the technique has been applied to measure changes in perfusion in response to infusion of vasoactive medications and maneuvers such as cardiopulmonary bypass. The results of current trials investigating the application of RS in critical care monitoring and vascular interventions will likely determine whether the technique will evolve from predominantly a research tool to a clinically useful device.
View details for PubMedID 15261201
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Continuous, noninvasive, and localized microvascular tissue oximetry using visible light spectroscopy
ANESTHESIOLOGY
2004; 100 (6): 1469-1475
Abstract
The authors evaluated the ability of visible light spectroscopy (VLS) oximetry to detect hypoxemia and ischemia in human and animal subjects. Unlike near-infrared spectroscopy or pulse oximetry (SpO2), VLS tissue oximetry uses shallow-penetrating visible light to measure microvascular hemoglobin oxygen saturation (StO2) in small, thin tissue volumes.In pigs, StO2 was measured in muscle and enteric mucosa during normoxia, hypoxemia (SpO2 = 40-96%), and ischemia (occlusion, arrest). In patients, StO2 was measured in skin, muscle, and oral/enteric mucosa during normoxia, hypoxemia (SpO2 = 60-99%), and ischemia (occlusion, compression, ventricular fibrillation).In pigs, normoxic StO2 was 71 +/- 4% (mean +/- SD), without differences between sites, and decreased during hypoxemia (muscle, 11 +/- 6%; P < 0.001) and ischemia (colon, 31 +/- 11%; P < 0.001). In patients, mean normoxic StO2 ranged from 68 to 77% at different sites (733 measures, 111 subjects); for each noninvasive site except skin, variance between subjects was low (e.g., colon, 69% +/- 4%, 40 subjects; buccal, 77% +/- 3%, 21 subjects). During hypoxemia, StO2 correlated with SpO2 (animals, r2 = 0.98; humans, r2 = 0.87). During ischemia, StO2 initially decreased at -1.3 +/- 0.2%/s and decreased to zero in 3-9 min (r2 = 0.94). Ischemia was distinguished from normoxia and hypoxemia by a widened pulse/VLS saturation difference (Delta < 30% during normoxia or hypoxemia vs. Delta > 35% during ischemia).VLS oximetry provides a continuous, noninvasive, and localized measurement of the StO2, sensitive to hypoxemia, regional, and global ischemia. The reproducible and narrow StO2 normal range for oral/enteric mucosa supports use of this site as an accessible and reliable reference point for the VLS monitoring of systemic flow.
View details for Web of Science ID 000221551300018
View details for PubMedID 15166566
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Ligate and let go
GASTROINTESTINAL ENDOSCOPY
2003; 58 (3): 473-474
View details for Web of Science ID 000185132500039
View details for PubMedID 14528239
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Measurement of mucosal capillary hemoglobin oxygen saturation in the colon by reflectance spectrophotometry
GASTROINTESTINAL ENDOSCOPY
2003; 57 (4): 492-497
Abstract
Advances in optical and computer technology have enabled the development of a device that uses white-light reflectance spectrophotometry to measure capillary hemoglobin saturation in intestinal mucosa during colonoscopy.Studies were performed with the colon oximeter in anesthetized animals and patients undergoing colonoscopy.Mean (SD) mucosal hemoglobin saturation in the normal colon was 72% (3.5%). In an animal model, ischemia induced by arterial ligation and hypoxemia via hypoxic ventilation each resulted in a decrease of over 40% in the mucosal saturation. In patients with colon polyps, ischemia induced by epinephrine injection, stalk ligation with a loop, or clipping of the polyp stalk each resulted in a decrease of over 40% in the mucosal saturation (p < 0.02). In contrast, saline solution injection did not decrease the mucosal saturation.A novel device for measuring capillary hemoglobin saturation in intestinal mucosa during colonoscopy is capable of providing reproducible measurements in normal patients and clearly detects dramatic decreases in saturation with ischemic and hypoxic insults.
View details for DOI 10.1067/mge.2003.162
View details for Web of Science ID 000182004400009
View details for PubMedID 12665758
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Quantitative clinical non-pulsatile and localized visible light oximeter: Design of the T-Stat (TM) tissue oximeter
Conference on Optical Tomography and Spectrosopy of Tissue V
SPIE-INT SOC OPTICAL ENGINEERING. 2003: 355–368
View details for Web of Science ID 000186054000040
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Measurement of mucosal capillary hemoglobin oxygen saturation in the colon by reflectance spectrophotometry
Conference on Lasers in Surgery - Advanced Characterization, Therapeutics and Systems XIII
SPIE-INT SOC OPTICAL ENGINEERING. 2003: 405–412
View details for Web of Science ID 000184498100052
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Gastric pancreatic rest leading to pyogenic liver abscess
GASTROINTESTINAL ENDOSCOPY
2002; 56 (3): 438-440
View details for DOI 10.1067/mge.2002.126619
View details for Web of Science ID 000177775800026
View details for PubMedID 12196792
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Bedside scoring system to predict the risk of developing pancreatitis following ERCP
ENDOSCOPY
2002; 34 (6): 483-488
Abstract
Pancreatitis is the most common significant complication of endoscopic retrograde cholangiopancreatography (ERCP). The aim of the present study was to develop a simple scoring system that clinicians can use to predict the risk of post-ERCP pancreatitis.We analyzed a prospectively assembled database of 1835 ERCP procedures at a single referral hospital. Multivariate logistic regression analysis was performed to identify risk factors for pancreatitis and determine their relative contributions. From these results, a scoring system was constructed. The performance of the scoring system was assessed on the entire procedure database and in selected subgroups.Multivariate analysis yielded four risk factors: pain during the procedure, cannulation of the pancreatic duct (PD), previous post-ERCP pancreatitis, and number of cannulation attempts. Based on the regression model, the scoring system was: 4 points for pain, 3 points for PD cannulation, 2 points for a history of post-ERCP pancreatitis, and 1 - 4 points depending on the number of cannulation attempts. A total score of 1 - 4 points was associated with a low risk of pancreatitis (< 2 %), while a score of 5 - 8 points had an intermediate risk (7 %), and a score of 9 or above had a high risk (28 %).This simple scoring system may enable clinicians to stratify patients into low-risk, medium-risk, and high-risk groups for the development of post-ERCP pancreatitis. In addition, when patients with suspected sphincter of Oddi dysfunction and patients who underwent minor papilla cannulation were analyzed separately, the scoring system was able to predict accurately the pancreatitis risk of these patients as well.
View details for Web of Science ID 000176079300011
View details for PubMedID 12048633
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Preoperative evaluation of submucosal invasive colorectal cancer using a 15-MHZ ultrasound miniprobe.
Gastrointestinal endoscopy
2002; 55 (7): 959-961
View details for PubMedID 12024172
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A novel method to control severe upper GI bleeding from metastatic cancer with a hemostatic sealant: the CoStasis surgical hemostat
GASTROINTESTINAL ENDOSCOPY
2002; 55 (6): 735-740
View details for DOI 10.1067/mge.2002.122796
View details for Web of Science ID 000175455300024
View details for PubMedID 11979262
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Placement of esophageal self-expandable metallic stents without fluoroscopy
GASTROINTESTINAL ENDOSCOPY
2001; 54 (3): 420-420
View details for Web of Science ID 000170784600034
View details for PubMedID 11522998
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Stenting the sigmoid colon in a terminally ill patient with prostate cancer.
Journal of palliative medicine
2001; 4 (2): 153-156
Abstract
Large bowel obstruction in the terminally ill patient can be difficult to manage. We describe a patient with sigmoid colon obstruction caused by metastatic prostate cancer in the pelvis who required hospitalization because of severe pain and obstructive symptoms. Treatment with an endoscopically placed self-expandable metal stent allowed the patient to have immediate resolution of symptoms and to receive hospice care at home.
View details for PubMedID 11441623
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Lift and ligate: a new technique to treat a bleeding polypectomy stump
GASTROINTESTINAL ENDOSCOPY
2000; 52 (5): 681-683
View details for Web of Science ID 000165148900021
View details for PubMedID 11060200
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Long-term follow-up of patients with chronic hepatitis B: A 25 year prospective study.
WILEY-BLACKWELL. 1999: 300A–300A
View details for Web of Science ID 000082794700557