Clinical Focus

  • Urology
  • Urologic Oncology

Academic Appointments

Honors & Awards

  • Member, Alpha Omega Alpha (07/2011)

Professional Education

  • Residency: Stanford School of Medicine (2021) CA
  • Internship: Stanford School of Medicine (2016) CA
  • Medical Education: UCLA David Geffen School Of Medicine Registrar (2015) CA

Lab Affiliations

  • Joseph Liao, Molecular Biosensor and Imaging Laboratory (5/17/2020)

All Publications

  • An Efficient Framework for Video Documentation of Bladder Lesions for Cystoscopy: A Proof-of-Concept Study. Journal of medical systems Eminaga, O., Ge, T. J., Shkolyar, E., Laurie, M. A., Lee, T. J., Hockman, L., Jia, X., Xing, L., Liao, J. C. 2022; 46 (11): 73


    Processing full-length cystoscopy videos is challenging for documentation and research purposes. We therefore designed a surgeon-guided framework to extract short video clips with bladder lesions for more efficient content navigation and extraction. Screenshots of bladder lesions were captured during transurethral resection of bladder tumor, then manually labeled according to case identification, date, lesion location, imaging modality, and pathology. The framework used the screenshot to search for and extract a corresponding 10-seconds video clip. Each video clip included a one-second space holder with a QR barcode informing the video content. The success of the framework was measured by the secondary use of these short clips and the reduction of storage volume required for video materials. From 86 cases, the framework successfully generated 249 video clips from 230 screenshots, with 14 erroneous video clips from 8 screenshots excluded. The HIPPA-compliant barcodes provided information of video contents with a 100% data completeness. A web-based educational gallery was curated with various diagnostic categories and annotated frame sequences. Compared with the unedited videos, the informative short video clips reduced the storage volume by 99.5%. In conclusion, our framework expedites the generation of visual contents with surgeon's instruction for cystoscopy and potential incorporation of video data towards applications including clinical documentation, education, and research.

    View details for DOI 10.1007/s10916-022-01862-8

    View details for PubMedID 36190581

  • Artificial Intelligence-Based Prognostic Model for Urologic Cancers: A SEER-Based Study. Cancers Eminaga, O., Shkolyar, E., Breil, B., Semjonow, A., Boegemann, M., Xing, L., Tinay, I., Liao, J. C. 2022; 14 (13)


    BACKGROUND: Prognostication is essential to determine the risk profile of patients with urologic cancers.METHODS: We utilized the SEER national cancer registry database with approximately 2 million patients diagnosed with urologic cancers (penile, testicular, prostate, bladder, ureter, and kidney). The cohort was randomly divided into the development set (90%) and the out-held test set (10%). Modeling algorithms and clinically relevant parameters were utilized for cancer-specific mortality prognosis. The model fitness for the survival estimation was assessed using the differences between the predicted and observed Kaplan-Meier estimates on the out-held test set. The overall concordance index (c-index) score estimated the discriminative accuracy of the survival model on the test set. A simulation study assessed the estimated minimum follow-up duration and time points with the risk stability.RESULTS: We achieved a well-calibrated prognostic model with an overall c-index score of 0.800 (95% CI: 0.795-0.805) on the representative out-held test set. The simulation study revealed that the suggestions for the follow-up duration covered the minimum duration and differed by the tumor dissemination stages and affected organs. Time points with a high likelihood for risk stability were identifiable.CONCLUSIONS: A personalized temporal survival estimation is feasible using artificial intelligence and has potential application in clinical settings, including surveillance management.

    View details for DOI 10.3390/cancers14133135

    View details for PubMedID 35804904

  • Bladder cancer risk stratification using a urinary mRNA biomarker panel - A path towards cystoscopy triaging. Urologic oncology Shkolyar, E., Zhao, Q., Mach, K. E., Teslovich, N. C., Lee, T. J., Cox, S., Skinner, E. C., Lu, Y., Liao, J. C. 2021


    OBJECTIVES: The risk of bladder cancer (BCa) diagnosis and recurrence necessitates cystoscopy. Improved risk stratification may inform personalized triage and surveillance strategies. We aim to develop a urinary mRNA biomarker panel for risk stratification in patients undergoing BCa screening and surveillance.METHODS AND MATERIALS: Urine samples were collected from patients undergoing cystoscopy for BCa screening or surveillance. In patients who underwent transurethral resection of bladder tumor, urine samples were categorized based on tumor histopathology, size, and focality. Subjects with intermediate and high-risk BCa based on American Urological Association (AUA) guideline for non-muscle invasive bladder cancer were classified as "increased-risk"; those with no cancer and AUA low-risk BCa were classified as "low-risk". Urine was evaluated for ROBO1, WNT5A, CDC42BPB, ABL1, CRH, IGF2, ANXA10, and UPK1B expression. A diagnostic model to detect "increased-risk" BCa was created using forward logistic regression analysis of cycle threshold values. Model validation was performed with ten-fold cross-validation. Sensitivity and specificity for detection of "increased-risk" BCa was determined and net benefit analysis performed.RESULTS: Urine samples (n = 257) were collected from 177 patients (95 screening, 76 surveillance, 6 both). There were 65 diagnoses of BCa (12 low, 22 intermediate, 31 high risk). ROBO1, CRH, and IGF2 expression correlated with "increased-risk" disease yielding sensitivity of 92.5% (95% CI, 84.9%-98.1%) and specificity of 73.5% (95% CI, 67.7-79.9%). The overall calculated standardized net benefit of the model was 0.81 (95%CI, 0.71-0.90).CONCLUSIONS: A 3-marker urinary mRNA panel allows for non-invasive identification of "increased-risk" BCa and with further validation may prove to be a tool to reduce the need for cystoscopies in low-risk patients.

    View details for DOI 10.1016/j.urolonc.2021.02.011

    View details for PubMedID 33766467

  • Current Trends in Artificial Intelligence Application for Endourology and Robotic Surgery. The Urologic clinics of North America Chang, T. C., Seufert, C., Eminaga, O., Shkolyar, E., Hu, J. C., Liao, J. C. 2021; 48 (1): 151–60


    With the advent of electronic medical records and digitalization of health care over the past 2decades, artificial intelligence (AI) has emerged as an enabling tool to manage complex datasets and deliver streamlined data-driven patient care. AI algorithms have the ability to extract meaningful signal from complex datasets through an iterative process akin to human learning. Through advancements over the past decade in deep learning, AI-driven innovations have accelerated applications in health care. Herein, the authors explore the development of these emerging AI technologies, focusing on the application of AI to endourology and robotic surgery.

    View details for DOI 10.1016/j.ucl.2020.09.004

    View details for PubMedID 33218590

  • Modeling the contribution of the obesity epidemic to the temporal decline in sperm counts. Archivio italiano di urologia, andrologia : organo ufficiale [di] Societa italiana di ecografia urologica e nefrologica Kasman, A., Del Giudice, F., Shkolyar, E., Porreca, A., Busetto, G. M., Lu, Y., Eisenberg, M. L. 2020; 92 (4)


    OBJECTIVE: Total sperm count (TSC) has been declining worldwide over the last several decades due to unknown etiologies. Our aim was to model the contribution that the obesity epidemic may have on declining TSC.MATERIALS AND METHODS: Obesity rates were determined since 1973 using the WHO's Global Health Observatory data. A literature review was performed to determine the association between TSC and obesity. Using the measured obesity rates and published TSC since 1973, a model was created to evaluate the association between temporal trends in obesity/temperature and sperm count.RESULTS: Since 1973, obesity prevalence in the United States was increased from 41% to 67.9%. A review of the literature showed that body mass index (BMI) categories 2, 3, and 4 were associated with TSC (millions) of 164.27, 155.71, and 142.29, respectively. The contribution to change over time for obesity from 1974 to 2011 was modeled at 1.8%. When the model was changed to represent the most extreme possible contribution to obesity reported, the modeled change over time rose to 7.2%. When stratified according to fertility status, the contribution that BMI had to falling sperm counts for all comers was 1.7%, while those presenting for fertility evaluation was 2.1%.CONCLUSIONS: While the decline in TSC may be partially due to rising obesity rates, these contributions are minimal which highlights the complexity of this problem.

    View details for DOI 10.4081/aiua.2020.4.357

    View details for PubMedID 33348967

  • Critical Appraisal of Quality Improvement Publications in the Urological Literature UROLOGY PRACTICE Greenberg, D. R., Sohlberg, E. M., Shkolyar, E., Shah, J. B. 2020; 7 (5): 413–17
  • Development of robust artificial neural networks for prediction of 5-year survival in bladder cancer. Urologic oncology Bhambhvani, H. P., Zamora, A., Shkolyar, E., Prado, K., Greenberg, D. R., Kasman, A. M., Liao, J., Shah, S., Srinivas, S., Skinner, E. C., Shah, J. B. 2020


    PURPOSE: When exploring survival outcomes for patients with bladder cancer, most studies rely on conventional statistical methods such as proportional hazards models. Given the successful application of machine learning to handle big data in many disciplines outside of medicine, we sought to determine if machine learning could be used to improve our ability to predict survival in bladder cancer patients. We compare the performance of artificial neural networks (ANN), a type of machine learning algorithm, with that of multivariable Cox proportional hazards (CPH) models in the prediction of 5-year disease-specific survival (DSS) and overall survival (OS) in patients with bladder cancer.SUBJECTS AND METHODS: The National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) 18 program database was queried to identify adult patients with bladder cancer diagnosed between 1995 and 2010, yielding 161,227 patients who met our inclusion criteria. ANNs were trained and tested on an 80/20 split of the dataset. Multivariable CPH models were developed in parallel. Variables used for prediction included age, sex, race, grade, SEER stage, tumor size, lymph node involvement, degree of extension, and surgery received. The primary outcomes were 5-year DSS and 5-year OS. Receiver operating characteristic curve analysis was conducted, and ANN models were tested for calibration.RESULTS: The area under the curve for the ANN models was 0.81 for the OS model and 0.80 for the DSS model. Area under the curve for the CPH models was 0.70 for OS and 0.81 for DSS. The ANN OS model achieved a calibration slope of 1.03 and a calibration intercept of -0.04, while the ANN DSS model achieved a calibration slope of 0.99 and a calibration intercept of -0.04.CONCLUSIONS: Machine learning algorithms can improve our ability to predict bladder cancer prognosis. Compared to CPH models, ANNs predicted OS more accurately and DSS with similar accuracy. Given the inherent limitations of administrative datasets, machine learning may allow for optimal interpretation of the complex data they contain.

    View details for DOI 10.1016/j.urolonc.2020.05.009

    View details for PubMedID 32593506

  • SLIPS-LAB-A bioinspired bioanalysis system for metabolic evaluation of urinary stone disease. Science advances Li, H., Shkolyar, E., Wang, J., Conti, S., Pao, A. C., Liao, J. C., Wong, T. S., Wong, P. K. 2020; 6 (21)


    Urinary stone disease is among the most common medical conditions. Standard evaluation of urinary stone disease involves a metabolic workup of stone formers based on measurement of minerals and solutes excreted in 24-hour urine samples. Nevertheless, 24-hour urine testing is slow, expensive, and inconvenient for patients, which has hindered widespread adoption in clinical practice. Here, we demonstrate SLIPS-LAB (Slippery Liquid-Infused Porous Surface Laboratory), a droplet-based bioanalysis system, for rapid measurement of urinary stone-associated analytes. The ultra-repellent and antifouling properties of SLIPS, which is a biologically inspired surface technology, allow autonomous liquid handling and manipulation of physiological samples without complicated sample preparation procedures and supporting equipment. We pilot a study that examines key urinary analytes in clinical samples from patients with urinary stone. The simplicity and speed of SLIPS-LAB hold the potential to provide actionable diagnostic information for patients with urinary stone disease and rapid feedback for responses to dietary and pharmacologic treatments.

    View details for DOI 10.1126/sciadv.aba8535

    View details for PubMedID 32937323

  • Editorial Comment. The Journal of urology Shkolyar, E., Mach, K. E., Liao, J. C. 2020: 101097JU000000000000078601

    View details for DOI 10.1097/JU.0000000000000786.01

    View details for PubMedID 32282282

  • REAL-TIME AUGMENTED BLADDER TUMOR DETECTION WITH DEEP LEARNING Chang, T., Shkolyar, E., Jia, X., Lee, T., Mach, K., Conti, S., Xing, L., Liao, J. LIPPINCOTT WILLIAMS & WILKINS. 2020: E1110
  • SLIPS-LAB-A bioinspired bioanalysis system for metabolic evaluation of urinary stone disease. Science advances Li, H. n., Shkolyar, E. n., Wang, J. n., Conti, S. n., Pao, A. C., Liao, J. C., Wong, T. S., Wong, P. K. 2020; 6 (21): eaba8535


    Urinary stone disease is among the most common medical conditions. Standard evaluation of urinary stone disease involves a metabolic workup of stone formers based on measurement of minerals and solutes excreted in 24-hour urine samples. Nevertheless, 24-hour urine testing is slow, expensive, and inconvenient for patients, which has hindered widespread adoption in clinical practice. Here, we demonstrate SLIPS-LAB (Slippery Liquid-Infused Porous Surface Laboratory), a droplet-based bioanalysis system, for rapid measurement of urinary stone-associated analytes. The ultra-repellent and antifouling properties of SLIPS, which is a biologically inspired surface technology, allow autonomous liquid handling and manipulation of physiological samples without complicated sample preparation procedures and supporting equipment. We pilot a study that examines key urinary analytes in clinical samples from patients with urinary stone. The simplicity and speed of SLIPS-LAB hold the potential to provide actionable diagnostic information for patients with urinary stone disease and rapid feedback for responses to dietary and pharmacologic treatments.

    View details for DOI 10.1126/sciadv.aba8535

    View details for PubMedID 32494753

    View details for PubMedCentralID PMC7244315

  • Robotic-Assisted Radical Prostatectomy Associated With Decreased Persistent Postoperative Opioid Use. Journal of endourology Shkolyar, E. n., Shih, I. F., Li, Y. n., Wong, J. n., Liao, J. C. 2020


    Minimally invasive surgery offers reduced pain and opioid use postoperatively compared to open surgery, but large-scale comparative studies are lacking. We assessed the incidence of persistent opioid use after open and robotic-assisted radical prostatectomy.We performed a retrospective claims database cohort study of opioid-naive (i.e., no opioid prescriptions 30-180 days before index surgery) adult males who underwent radical prostatectomy for prostate cancer from July 2013-June 2017. For patients who filled a perioperative opioid prescription (30 days before to 14 days after surgery), we calculated the incidence of new persistent postoperative opioid use (≥1 prescription 90-180 days after surgery). Multivariable logistic regression was performed to investigate the association between surgical approach, patient risk factors and persistent opioid use.12,278 radical prostatectomy patients filled an opioid prescription perioperatively (1510 [12%] open, 10,768 [88%] robotic-assisted). Of these, 846 (6.9%) patients continued to fill opioid prescription(s) 90-180 days after surgery. Patients undergoing robotic-assisted radical prostatectomy were 35% less likely to develop new persistent opioid use compared to those undergoing open radical prostatectomy (6.5% vs 9.7%; adjusted OR 0.65; 95% CI 0.54-0.79). Other independent risk factors included living in the southern, western or northcentral United States, preoperative comorbidity and tobacco use.Approximately 6.9% of opioid-naive patients continued to fill opioid prescriptions 90 days after radical prostatectomy. The risk of persistent opioid use was significantly lower among patients undergoing a robotic-assisted versus open approach. Further efforts are needed to develop postoperative opioid prescription protocols for patients undergoing radical prostatectomy.

    View details for DOI 10.1089/end.2019.0788

    View details for PubMedID 32066277

  • Ultra-low-dose CT: An Effective Follow-up Imaging Modality for Ureterolithiasis. Journal of endourology Cheng, R. Z., Shkolyar, E., Chang, T. C., Spradling, K., Ganesan, C., Song, S., Pao, A. C., Leppert, J. T., Elliott, C. S., To'o, K., Conti, S. L. 2019


    BACKGROUND AND PURPOSE: Classically, abdominal X-ray (KUB), ultrasound or a combination of both have been routinely used for ureteral stone surveillance after initial diagnosis. More recently, ultra-low-dose CT (ULD CT) has emerged as a CT technique that reduces radiation dose while maintaining high sensitivity and specificity for urinary stone detection. We aim to evaluate our initial experience with ULD CT for patients with ureterolithiasis, measuring real-world radiation doses and stone detection performance.METHODS: We reviewed all ULD CT scans performed at the Veterans Affairs Palo Alto Health Care System between 2016 and 2018. We included patients with ureteral stones and calculated the mean effective radiation dose per scan. We determined stone location and size, if the stone was visible on the associated KUB or CT scout film, and if hydronephrosis was present. We performed logistic regression to identify variables associated with visibility on KUB or CT scout film and hydronephrosis.RESULTS: One-hundred and eighteen ULD scans were reviewed, of which 50 detected ureteral stones. The mean effective radiation dose was 1.04 ± 0.41 mSv. Of the ULD CTs that detected ureterolithiasis, 38% lacked visibility on KUB/CT scout film and had no associated hydronephrosis, suggesting they would be missed with a combination of KUB and ultrasound. Larger stones (OR: 1.40, 95% CI: 1.08-1.96 for every 1mm increase in stone size) were more likely to be detected by KUB/CT scout or ultrasound, while stones in the distal ureter (OR: 0.18, 95% CI: 0.03-0.81) were more likely to be missed by KUB/CT scout or hydronephrosis.CONCLUSION: Based on our institutions' initial experience with ULD CT, ULD CT detects small and distal ureteral stones that would likely be missed by KUB or ultrasound, while maintaining a low effective radiation dose. An ULD CT protocol should be considered when re-imaging for ureteral stones is necessary.

    View details for DOI 10.1089/end.2019.0574

    View details for PubMedID 31663371

  • Optical biopsy of penile cancer with in vivo confocal laser endomicroscopy. Urologic oncology Shkolyar, E. n., Laurie, M. A., Mach, K. E., Trivedi, D. R., Zlatev, D. V., Chang, T. C., Metzner, T. J., Leppert, J. T., Kao, C. S., Liao, J. C. 2019


    Surgical management of penile cancer depends on accurate margin assessment and staging. Advanced optical imaging technologies may improve penile biopsy and organ-sparing treatment. We evaluated the feasibility of confocal laser endomicroscopy for intraoperative assessment of benign and malignant penile tissue.With institutional review board approval, 11 patients were recruited, 9 with suspected penile cancer, and 2 healthy controls. Confocal laser endomicroscopy using a 2.6-mm fiber-optic probe was performed at 1 or 2 procedures on all subjects, for 13 imaging procedures. Fluorescein was administered intravenously approximately 3 minutes prior to imaging for contrast. Video sequences from in vivo (n = 12) and ex vivo (n = 6) imaging were obtained of normal glans, suspicious lesions, and surgical margins. Images were processed, annotated, characterized, and correlated with standard hematoxylin and eosin histopathology.No adverse events related to imaging were reported. Distinguishing features of benign and malignant penile tissue could be identified by confocal laser endomicroscopy. Normal skin had cells of uniform size and shape, with distinct cytoplasmic membranes consistent with squamous epithelium. Malignant lesions were characterized by disorganized, crowded cells of various size and shape, lack of distinct cytoplasmic membranes, and hazy, moth-eaten appearance. The transition from normal to abnormal squamous epithelium could be identified.We report the initial feasibility of intraoperative confocal laser endomicroscopy for penile cancer optical biopsy. Pending further evaluation, confocal laser endomicroscopy could serve as an adjunct or replacement to conventional frozen section pathology for management of penile cancer.

    View details for DOI 10.1016/j.urolonc.2019.08.018

    View details for PubMedID 31537485

  • Augmented Bladder Tumor Detection Using Deep Learning. European urology Shkolyar, E. n., Jia, X. n., Chang, T. C., Trivedi, D. n., Mach, K. E., Meng, M. Q., Xing, L. n., Liao, J. C. 2019


    Adequate tumor detection is critical in complete transurethral resection of bladder tumor (TURBT) to reduce cancer recurrence, but up to 20% of bladder tumors are missed by standard white light cystoscopy. Deep learning augmented cystoscopy may improve tumor localization, intraoperative navigation, and surgical resection of bladder cancer. We aimed to develop a deep learning algorithm for augmented cystoscopic detection of bladder cancer. Patients undergoing cystoscopy/TURBT were recruited and white light videos were recorded. Video frames containing histologically confirmed papillary urothelial carcinoma were selected and manually annotated. We constructed CystoNet, an image analysis platform based on convolutional neural networks, for automated bladder tumor detection using a development dataset of 95 patients for algorithm training and five patients for testing. Diagnostic performance of CystoNet was validated prospectively in an additional 54 patients. In the validation dataset, per-frame sensitivity and specificity were 90.9% (95% confidence interval [CI], 90.3-91.6%) and 98.6% (95% CI, 98.5-98.8%), respectively. Per-tumor sensitivity was 90.9% (95% CI, 90.3-91.6%). CystoNet detected 39 of 41 papillary and three of three flat bladder cancers. With high sensitivity and specificity, CystoNet may improve the diagnostic yield of cystoscopy and efficacy of TURBT. PATIENT SUMMARY: Conventional cystoscopy has recognized shortcomings in bladder cancer detection, with implications for recurrence. Cystoscopy augmented with artificial intelligence may improve cancer detection and resection.

    View details for DOI 10.1016/j.eururo.2019.08.032

    View details for PubMedID 31537407

  • Risk of Melanoma With Phosphodiesterase Type 5 Inhibitor Use Among Patients With Erectile Dysfunction, Pulmonary Hypertension, and Lower Urinary Tract Symptoms JOURNAL OF SEXUAL MEDICINE Shkolyar, E., Li, S., Tang, J., Eisenberg, M. L. 2018; 15 (7): 982–89
  • Risk of Melanoma With Phosphodiesterase Type 5 Inhibitor Use Among Patients With Erectile Dysfunction, Pulmonary Hypertension, and Lower Urinary Tract Symptoms. The journal of sexual medicine Shkolyar, E., Li, S., Tang, J., Eisenberg, M. L. 2018


    BACKGROUND: Phosphodiesterase type 5 inhibitors (PDE5is), a treatment for erectile dysfunction, pulmonary hypertension (pHTN), and lower urinary tract symptoms (LUTS), have been implicated in melanoma development.AIM: We sought to determine the association between PDE5i use and melanoma development among patients with erectile dysfunction, pHTN, and LUTS.METHODS: This was a retrospective cohort study of subjects contained within the Truven Health MarketScan claims database, which provides information on insurance claims in the United States for privately insured individuals, from 2007-2015. Individuals taking PDE5i were identified through pharmacy claims. A comparison group of men diagnosed with conditions for which PDE5i are prescribed was assembled.OUTCOMES: Cox proportional hazard models were used to estimate the hazard ratio (HR) (95% CI) of incident melanoma, basal cell carcinoma, and squamous cell carcinoma.RESULTS: Of 610,881 subjects prescribed PDE5i, 636 developed melanoma (0.10%). The control group had 8,711 diagnoses of melanoma. There was an association between increased PDE5i tablet use and melanoma (HR1.05, 95% CI 1.05-1.09). This association was also present between PDE5i use and basal cell carcinoma (HR 1.04, 95% CI 1.02-1.07) and squamous cell carcinoma (HR 1.04, 95% CI 1.01-1.07). In patients with pHTN and LUTS prescribed PDE5is, there was no relationship between exposure and melanoma incidence (HR 0.74, 95% CI 0.48-1.13; and HR 1.03, 95% CI 0.97-1.10, respectively).CLINICAL IMPLICATIONS: There is little evidence for a clinically relevant association between PDE5i use and melanoma incidence.STRENGTHS & LIMITATIONS: Our current work represents the largest study to date evaluating the relationship between PDE5i use and melanoma risk, and the first to examine all current indications of PDE5i use among men and women. Limitations include a patient population limited to commercially insured individuals, unknown patient medication compliance, and lack of information on patient skin type, lifestyle, and sun-exposure habits.CONCLUSION: There is a slight association between higher-volume PDE5i use and development of melanoma, basal cell carcinoma, and squamous cell carcinoma. This association among all skin cancers implies that confounding may account for the observed association. Shkolyar E, Li S, Tang J, etal. Risk of Melanoma With Phosphodiesterase Type 5 Inhibitor Use Among Patients With Erectile Dysfunction, Pulmonary Hypertension, and Lower Urinary Tract Symptoms. J Sex Med 2018;XX:XXX-XXX.

    View details for PubMedID 29884444

  • Teaching mid-urethral sling surgery to residents: Impact on operative time and postoperative outcomes NEUROUROLOGY AND URODYNAMICS Sharif-Afshar, A., Wood, L. N., Bresee, C., Souders, C. P., Gross, B. S., Shkolyar, E., Anger, J. T., Eilber, K. S. 2017; 36 (8): 2148-2152


    The purpose of this study was to determine the impact of resident teaching on outcomes of mid-urethral sling surgery.A retrospective review of female patients who underwent an outpatient transobturator (TOT) synthetic mid-urethral sling procedure with and without concomitant prolapse repair by two surgeons (JA, KE) in a tertiary female pelvic medicine practice was performed. Total procedure time (TPT = time from incision to closure including sling placement and any prolapse procedure), estimated blood loss (EBL), and postoperative complications including urinary retention, mesh exposure, reoperation, vaginal bleeding, and leg pain were compared between cases with and without the presence of a resident.One hundred thirty-four women underwent an outpatient transobturator sling procedure. Fifty-seven patients (43%) had a concomitant prolapse procedure. A resident was present at 57% (76/134) of cases. The average observed TPT (±SEM) was 60.6 ± 3.1 min when a resident was present and 46.6 ± 2.5 min when a resident was not present (P = 0.001). However, residents were more likely to be present when concomitant procedures were performed (P = 0.003). After adjusting for this, the presence of a resident increased TPT by an estimated 7.9 ± 2.5 min (P = 0.002). There was no statistical difference in EBL or postoperative complications.Resident participation in transobturator sling procedures resulted in a statistically significant, although clinically small, increase in operative time and had no significant impact on EBL or postoperative complications.

    View details for DOI 10.1002/nau.23259

    View details for Web of Science ID 000414364400027

    View details for PubMedID 28370305

  • Nontraumatic Clostridium septicum Myonecrosis in Adults Case Report and a 15-Year Systematic Literature Review INFECTIOUS DISEASES IN CLINICAL PRACTICE Forrester, J. D., Shkolyar, E., Gregg, D., Spain, D. A., Weiser, T. G. 2016; 24 (6): 318–23
  • Impact of post prostate biopsy hemorrhage on multiparametric magnetic resonance imaging Canadian Journal of Urology Sharif-Afshar, A., Fen, T., Koopman, S., Christopher Nguyen, Li, Q., Shkolyar, E., Saouaf, R., Kim, H. L. 2015; 22 (2): 7698-7702


    Hemorrhage induced by prostate biopsy can interfere with the interpretation of prostate magnetic resonance imaging (MRI).We reviewed 101 patients who had prostate multiparametric MRI (MP-MRI) and radical prostatectomy.On MRI obtained within 4 weeks following the biopsy, hemorrhage was seen in 26/36 (72.2%) patients. Patients having a MRI between 4-6 weeks of the biopsy had hemorrhage in 8/14 (57.1%) cases. After 6 weeks, hemorrhage was less common but still present in 24/46 (52%) patients. There were five patients who had prostate MRI prior to biopsy and served as a control group. There was no significant correlation between the length of time beyond 6 weeks and the likelihood of having prostate hemorrhage on MRI. The overall sensitivity and specificity of MRI for predicting extracapsular extension (ECE) were 78.6% and 89%, respectively. However, if the analysis was limited to patients with MRI within 6 weeks from the time of biopsy, the sensitivity and specificity were similar: 80% and 90%, respectively. For patients with MRI obtained after 6 weeks, the sensitivity and specificity were 76.9% and 87.9%.Prostate hemorrhage is seen in the majority of cases within 6 weeks of biopsy and can be seen in nearly half the patients even beyond 6 weeks. However, hemorrhage within 6 weeks of a biopsy does not interfere with assessment for ECE.

    View details for Web of Science ID 000353434400004

    View details for PubMedID 25891332

  • Multifocality and Prostate Cancer Detection by Multiparametric Magnetic Resonance Imaging: Correlation with Whole-mount Histopathology EUROPEAN UROLOGY Le, J. D., Tan, N., Shkolyar, E., Lu, D. Y., Kwan, L., Marks, L. S., Huang, J., Margolis, D. A., Raman, S. S., Reiter, R. E. 2015; 67 (3): 569-576


    Multiparametric magnetic resonance imaging (mp-MRI) is increasingly used in prostate cancer (CaP). Understanding the limitations of tumor detection, particularly in multifocal disease, is important in its clinical application.To determine predictors of CaP detection by mp-MRI as confirmed by whole-mount histopathology.A retrospective study was performed of 122 consecutive men who underwent mp-MRI before radical prostatectomy at a single referral academic center. A genitourinary radiologist and pathologist collectively determined concordance.The odds of tumor detection were calculated for clinical, MRI, and histopathologic variables using a multivariate logistic regression model.The 122 patients had 283 unique histologically confirmed CaP tumor foci. Gleason score was 6 in 21 (17%), 7 in 88 (72%), and ≥8 in 13 (11%) patients. Of the 122 cases, 44 (36%) had solitary and 78 (64%) had multifocal tumors. Overall mp-MRI sensitivity for tumor detection was 47% (132/283), with increased sensitivity for larger (102/141 [72%] >1.0 cm), higher-grade (96/134 [72%] Gleason ≥7) tumors, and index tumors (98/122 [80%]). Index tumor status, size, and prostate weight were significant predictors of detection in a multivariate analysis, and multifocality did not adversely impact detection of index tumors. A prostatectomy population was necessary by design, which may limit the ability to generalize these results.Sensitivity for tumor detection increased with tumor size and grade. Index tumor status and tumor size were the strongest predictors of tumor detection, regardless of tumor focality. Some 80% of index tumors were detected, but nonindex tumor detection, even of high-grade lesions, was poor. These findings have important implications for focal therapy.We evaluated the ability of magnetic resonance imaging (MRI) to detect cancer in patients undergoing prostatectomy. We found that tumor size and grade were important predictors of tumor detection, and although cancer is often multifocal, MRI is often able to detect the worst focus of cancer.

    View details for DOI 10.1016/j.eururo.2014.08.079

    View details for Web of Science ID 000349374200039

    View details for PubMedID 25257029

  • In Vitro Evaluation of an External Compression Device for Fontan Mechanical Assistance ARTIFICIAL ORGANS Valdovinos, J., Shkolyar, E., Carman, G. P., Levi, D. S. 2014; 38 (3): 199-207


    While Fontan palliation in the form of the total cavopulmonary connection has improved the management of congenital single ventricle physiology, long-term outcomes for patients with this disease are suboptimal due to the lack of two functional ventricles. Researchers have shown that ventricular assist devices (VADs) can normalize Fontan hemodynamics. To minimize blood contacting surfaces of the VAD, we evaluated the use of an external compression device (C-Pulse Heart Assist System, Sunshine Heart Inc.) as a Fontan assist device. A mock circulation was developed to mimic the hemodynamics of a hypertensive Fontan circulation in a pediatric patient. The Sunshine C-Pulse compression cuff was coupled with polymeric valves and a compressible tube to provide nonblood-contacting pulsatile flow through the Fontan circulation. The effect of the number, one or two, and placement of valves, before or after the compression cuff, on inferior vena cava pressure (IVCP) was studied. In addition, the effect of device inflation volume and compression rate on maintaining low IVCP was investigated. With one valve located before the cuff, the device was unable to maintain an IVCP below 15.5 mm Hg. With two valves, the C-Pulse was able to maintain IVCP as low as 8.5 mm Hg. The C-Pulse provided pulsatile flow and pressure through the pulmonary branch of the mock circulation with a pulse pressure of 16 mm Hg and 180 mL/min additional flow above unassisted flow. C-Pulse compression reduced IVCP below 12 mm Hg with 13 cc inflation volume and compression rates above 105 bpm. This application of an external compression device combined with two valves has potential for use as an artificial right ventricle by maintaining low IVCP and providing pulsatile flow through the lungs.

    View details for DOI 10.1111/aor.12152

    View details for Web of Science ID 000333445800006

    View details for PubMedID 24147904