Robert Downey Boutin
Clinical Professor, Radiology
Web page: http://web.stanford.edu/people/boutin
Bio
Dr. Boutin works clinically as a musculoskeletal radiologist interpreting a broad array of diagnostic imaging examinations, most frequently MRI, CT, sonography, and radiography.
The clinical focus for Dr. Boutin is MRI of joints, bones, and muscles, as well as adding value to routine radiology exams by translating advancements from fields of artificial intelligence and imaging informatics.
These advancements include enhancing routine imaging exams to help promote physical function, quality of life, and health span in our patients. Because the worldwide population of people > 60 years of age is projected to double by 2050, there is a crucial need for improvements in the accurate and efficient management of derangements associated with biological aging, including osteoporosis, sarcopenia, and visceral adiposity.
Dr. Boutin is a leader in the field of musculoskeletal imaging. He has served as the Chair of the Musculoskeletal Imaging Program Committee for the largest medical meeting in the world (RSNA) and is the President of the Society of Academic Bone Radiologists. Core professional values include an emphasis on outstanding quality, compassion, safety, and integrity.
Dr. Boutin was introduced to Orthopaedics at an early age by his father and older brother -- both orthopaedists. After earning undergraduate and graduate degrees at Stanford University, Dr. Boutin completed advanced fellowship training in Musculoskeletal Imaging at the University of California, San Diego, and worked on the faculty at Harvard Medical School.
Dr. Boutin is dedicated to excellence in musculoskeletal imaging. Dr. Boutin has written over 100 peer-reviewed articles and textbook chapters. He has also served as Guest Editor for 2 volumes of the 'Orthopaedic Clinics of North America', and volumes of ‘Seminars in Musculoskeletal Radiology’. Dr. Boutin also has served for many years as a Peer Reviewer for premier radiology journals.
Dr. Boutin is a popular invited lecturer for Continuing Medical Education Courses, such as those at the annual meetings of the 'Radiological Society of North America', the 'International Skeletal Society', the 'Arthroscopy Association of North America', the 'American Academy of Orthopaedic Surgeons', and the 'International Society for Magnetic Resonance in Medicine'. He is also a repeat lecturer at the prestigious Orthopaedic Imaging course in Davos, Switzerland.
Clinical Focus
- Diagnostic Radiology
Academic Appointments
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Clinical Professor, Radiology
Administrative Appointments
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Chair, Appointments & Promotions Committee, Stanford University School of Medicine (2023 - 2025)
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Affiliated Faculty, Integrative Biomedical Imaging Informatics at Stanford (IBIIS) (2022 - Present)
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Director, Musculoskeletal Imaging Fellowship, Department of Radiology (2021 - Present)
Honors & Awards
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Musculoskeletal Imaging 2024: Lessons Learned, Society of Academic Bone Radiologists - The John Hunter Medal (2024)
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AI-Based CT for Assessment of Muscle Mass in Patients with Malnutrition and Denied Insurance Claims, Stanford Quality Improvement & Patient Safety Symposium - Innovation Winner (2024)
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Myositis and its Mimics, American Roentgen Ray Society (ARRS) (2024)
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Cachexia: Current Concepts and Imaging Implications, American Roentgen Ray Society (ARRS) (2024)
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Accessory Infraglenoid Muscle in Patients with and without Teres Minor Fatty Infiltration, ARRS - Magna Cum Laude Award (2024)
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Soft Tissue Tumors, RSNA - Cum Laude Award (2022)
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CMS and Calculators: Hospital Price Transparency Requirements and Imaging Cost Variability, American Roentgen Ray Society (ARRS) (2022)
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Liposclerosing Myxofibrous Tumor (LSMFT), Society of Skeletal Radiology (AIRP Award) (2022)
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Meniscus Roots, Ramps, Repairs, and Repercussions, RSNA - Magna Cum Laude Award (2021)
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The Sternum and Sternoclavicular Joints, RSNA - Magna Cum Laude Award (2021)
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Altered Biomechanics and Patterns of Injury in the Presence of Rotator Cuff Insufficiency, Radiological Society of North America (2020)
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Fast Musculoskeletal MRI: What the Radiologist Needs to Know, Radiological Society of North America (2019)
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Value-Added 'Opportunistic' CT: State-of-the-Art Insights into Bone, Muscle, and Fat, Radiological Society of North America (2019)
Boards, Advisory Committees, Professional Organizations
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Chair, RSNA Msk Meeting Program Committee (2021-22); RadioGraphics Subspecialty Panel (2021-24), Radiological Society of North America (RSNA) (1992 - Present)
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ISS Scientific Session Cmte (2021-24); Chair, Grants Cmte (2019-20); Chair, Audit Cmte (2017-18), International Skeletal Society (ISS) (2001 - Present)
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SABR President (2024 - 2026), Society of Academic Bone Radiologists (SABR) (2013 - Present)
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QIBA Musculoskeletal Biomarkers Committee (Articular Cartilage MRI), Quantitative Imaging Biomarkers Alliance (QIBA) (2019 - 2023)
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ARRS Musculoskeletal Radiology Scientific Program Committee (2011 - Present), American Roentgen Ray Society (ARRS) (1991 - Present)
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ACR Practice Parameters and Technical Standards Development (Quantitative CT Bone Densitometry; DXA), American College of Radiology (ACR) (2022 - Present)
Professional Education
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Fellowship, University of California San Diego School of Medicine, Musculoskeletal Radiology
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Board Certification, American Board of Radiology, Diagnostic Radiology
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Residency, UNM School of Medicine, Diagnostic Radiology
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Medical Degree, University of California Davis School of Medicine, Medicine
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Master's Degree, Stanford University, Biological Sciences
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Bachelor's Degree, Stanford University, Biological Sciences
All Publications
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Opportunistic Screening of Bone Fragility Using Computed Tomography.
Seminars in musculoskeletal radiology
2024; 28 (5): 620-627
Abstract
Opportunistic screening uses existing imaging studies for additional diagnostic insights without imposing further burden on patients. We explore the potential of opportunistic computed tomography (CT) screening for osteoporosis, a condition affecting 500 million people globally and leading to significant health care costs and fragility fractures. Although dual-energy X-ray absorptiometry (DXA) remains the gold standard for diagnosing osteoporosis, > 50% of fractures occur in individuals not screened previously with DXA. With recent advancements in technology, CT has emerged as the most promising tool for opportunistic screening due to its wide use and the ability to provide quantitative measurements of bone attenuation, a surrogate of bone mineral density. This article discusses the technical considerations, calibration methods, and potential benefits of CT for osteoporosis screening. It also explores the role of automation, supervised and unsupervised, in streamlining the diagnostic process, improving accuracy, and potentially developing new biomarkers of bone health. The potential addition of radiomics and genomics is also highlighted, showcasing the synergy between genetic and imaging data for a more comprehensive understanding of osteoporosis pathophysiology and with it possible novel osteoporosis therapies. The future of opportunistic CT screening holds significant promise, with automation and advanced image processing ultimately enhancing patient care, reducing rates of osteoporotic fractures, and improving patient outcomes.
View details for DOI 10.1055/s-0044-1788816
View details for PubMedID 39406224
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Editorial Comment: A New Chapter for Obesity-Glucagon-Like Peptide-1 Agonists and Body Composition Imaging.
AJR. American journal of roentgenology
2024
View details for DOI 10.2214/AJR.24.32045
View details for PubMedID 39291948
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Merlin: A Vision Language Foundation Model for 3D Computed Tomography.
Research square
2024
Abstract
Over 85 million computed tomography (CT) scans are performed annually in the US, of which approximately one quarter focus on the abdomen. Given the current shortage of both general and specialized radiologists, there is a large impetus to use artificial intelligence to alleviate the burden of interpreting these complex imaging studies while simultaneously using the images to extract novel physiological insights. Prior state-of-the-art approaches for automated medical image interpretation leverage vision language models (VLMs) that utilize both the image and the corresponding textual radiology reports. However, current medical VLMs are generally limited to 2D images and short reports. To overcome these shortcomings for abdominal CT interpretation, we introduce Merlin - a 3D VLM that leverages both structured electronic health records (EHR) and unstructured radiology reports for pretraining without requiring additional manual annotations. We train Merlin using a high-quality clinical dataset of paired CT scans (6+ million images from 15,331 CTs), EHR diagnosis codes (1.8+ million codes), and radiology reports (6+ million tokens) for training. We comprehensively evaluate Merlin on 6 task types and 752 individual tasks. The non-adapted (off-the-shelf) tasks include zero-shot findings classification (31 findings), phenotype classification (692 phenotypes), and zero-shot cross-modal retrieval (image to findings and image to impressions), while model adapted tasks include 5-year chronic disease prediction (6 diseases), radiology report generation, and 3D semantic segmentation (20 organs). We perform internal validation on a test set of 5,137 CTs, and external validation on 7,000 clinical CTs and on two public CT datasets (VerSe, TotalSegmentator). Beyond these clinically-relevant evaluations, we assess the efficacy of various network architectures and training strategies to depict that Merlin has favorable performance to existing task-specific baselines. We derive data scaling laws to empirically assess training data needs for requisite downstream task performance. Furthermore, unlike conventional VLMs that require hundreds of GPUs for training, we perform all training on a single GPU. This computationally efficient design can help democratize foundation model training, especially for health systems with compute constraints. We plan to release our trained models, code, and dataset, pending manual removal of all protected health information.
View details for DOI 10.21203/rs.3.rs-4546309/v1
View details for PubMedID 38978576
View details for PubMedCentralID PMC11230513
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Myositis and Its Mimics: Guideline Updates, MRI Characteristics, and New Horizons.
AJR. American journal of roentgenology
2024
Abstract
Myositis is defined as inflammation within skeletal muscle and is a subcategory of myopathy, which is more broadly defined as any disorder affecting skeletal muscle. Myositis may be encountered as a component of autoimmune and connective tissue disease, where it is described as idiopathic inflammatory myopathy. Myositis can also be caused by infections, as well as toxins and drugs, including newer classes of medications. MRI plays an important role in the diagnosis and evaluation of patients with suspected myositis, but many entities may have imaging features similar to myositis and can be considered myositis mimics. These include muscular dystrophies, denervation, deep venous thrombosis, diabetic myonecrosis, muscle injury, heterotopic ossification, and even neoplasms. In patients with suspected myositis, definitive diagnosis may require integrated analysis of imaging findings with clinical, laboratory, and pathology data. The objectives of this article are to review the fundamental features of myositis, including recent updates in terminology and consensus guidelines for idiopathic inflammatory myopathies, the most important MRI differential diagnostic considerations for myositis (i.e., myositis mimics), and new horizons, including the potential importance of artificial intelligence and multimodal integrated diagnostics in the evaluation of patients with muscle disorders.
View details for DOI 10.2214/AJR.24.31359
View details for PubMedID 38838235
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MRI of Soft-Tissue Tumors: What to Include in the Report.
Radiographics : a review publication of the Radiological Society of North America, Inc
2024; 44 (6): e230086
Abstract
MRI serves as a critical step in the workup, local staging, and treatment planning of extremity soft-tissue masses. For the radiologist to meaningfully contribute to the management of soft-tissue masses, they need to provide a detailed list of descriptors of the lesion outlined in an organized report. While it is occasionally possible to use MRI to provide a diagnosis for patients with a mass, it is more often used to help with determining the differential diagnosis and planning of biopsies, surgery, radiation treatment, and chemotherapy (when provided). Each descriptor on the list outlined in this article is specifically aimed to assist in one or more facets of the overall approach to soft-tissue masses. This applies to all masses, but in particular sarcomas. Those descriptors are useful to help narrow the differential diagnosis and ensure concordance with a pathologic diagnosis and its accompanying grade assignment of soft-tissue sarcomas. These include a lesion's borders and shape, signal characteristics, and contrast enhancement pattern; the presence of peritumoral edema and peritumoral enhancement; and the presence of lymph nodes. The items most helpful in assisting surgical planning include a lesion's anatomic location, site of origin, size, location relative to a landmark, relationship to adjacent structures, and vascularity including feeding and draining vessels. The authors provide some background information on soft-tissue sarcomas, including their diagnosis and treatment, for the general radiologist and as a refresher for radiologists who are more experienced in tumor imaging. ©RSNA, 2024 See the invited commentary by Murphey in this issue.
View details for DOI 10.1148/rg.230086
View details for PubMedID 38696323
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A randomized phase II study of gemcitabine and nab-paclitaxel compared with 5-fluorouracil, leucovorin, and liposomal irinotecan in older patients with treatment-naive metastatic pancreatic cancer (GIANT): ECOG-ACRIN EA2186.
LIPPINCOTT WILLIAMS & WILKINS. 2024
View details for Web of Science ID 001275557400878
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Abdominal CT metrics in 17,646 patients reveal associations between myopenia, myosteatosis, and medical phenotypes: a phenome-wide association study
EBIOMEDICINE
2024; 103
View details for DOI 10.1051161016/j.ebiom.2024.105116
View details for Web of Science ID 001231570700001
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Automated abdominal CT contrast phase detection using an interpretable and open-source artificial intelligence algorithm.
European radiology
2024
Abstract
To develop and validate an open-source artificial intelligence (AI) algorithm to accurately detect contrast phases in abdominal CT scans.Retrospective study aimed to develop an AI algorithm trained on 739 abdominal CT exams from 2016 to 2021, from 200 unique patients, covering 1545 axial series. We performed segmentation of five key anatomic structures-aorta, portal vein, inferior vena cava, renal parenchyma, and renal pelvis-using TotalSegmentator, a deep learning-based tool for multi-organ segmentation, and a rule-based approach to extract the renal pelvis. Radiomics features were extracted from the anatomical structures for use in a gradient-boosting classifier to identify four contrast phases: non-contrast, arterial, venous, and delayed. Internal and external validation was performed using the F1 score and other classification metrics, on the external dataset "VinDr-Multiphase CT".The training dataset consisted of 172 patients (mean age, 70 years ± 8, 22% women), and the internal test set included 28 patients (mean age, 68 years ± 8, 14% women). In internal validation, the classifier achieved an accuracy of 92.3%, with an average F1 score of 90.7%. During external validation, the algorithm maintained an accuracy of 90.1%, with an average F1 score of 82.6%. Shapley feature attribution analysis indicated that renal and vascular radiodensity values were the most important for phase classification.An open-source and interpretable AI algorithm accurately detects contrast phases in abdominal CT scans, with high accuracy and F1 scores in internal and external validation, confirming its generalization capability.Contrast phase detection in abdominal CT scans is a critical step for downstream AI applications, deploying algorithms in the clinical setting, and for quantifying imaging biomarkers, ultimately allowing for better diagnostics and increased access to diagnostic imaging.Digital Imaging and Communications in Medicine labels are inaccurate for determining the abdominal CT scan phase. AI provides great help in accurately discriminating the contrast phase. Accurate contrast phase determination aids downstream AI applications and biomarker quantification.
View details for DOI 10.1007/s00330-024-10769-6
View details for PubMedID 38683384
View details for PubMedCentralID 9700820
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Chronic Nonspinal Osteomyelitis in Adults: Consensus Recommendations on Percutaneous Bone Biopsies from the Society of Academic Bone Radiologists.
Radiology
2024; 311 (1): e231348
Abstract
The diagnosis and management of chronic nonspinal osteomyelitis can be challenging, and guidelines regarding the appropriateness of performing percutaneous image-guided biopsies to acquire bone samples for microbiological analysis remain limited. An expert panel convened by the Society of Academic Bone Radiologists developed and endorsed consensus statements on the various indications for percutaneous image-guided biopsies to standardize care and eliminate inconsistencies across institutions. The issued statements pertain to several commonly encountered clinical presentations of chronic osteomyelitis and were supported by a literature review. For most patients, MRI can help guide management and effectively rule out osteomyelitis when performed soon after presentation. Additionally, in the appropriate clinical setting, open wounds such as sinus tracts and ulcers, as well as joint fluid aspirates, can be used for microbiological culture to determine the causative microorganism. If MRI findings are positive, surgery is not needed, and alternative sites for microbiological culture are not available, then percutaneous image-guided biopsies can be performed. The expert panel recommends that antibiotics be avoided or discontinued for an optimal period of 2 weeks prior to a biopsy whenever possible. Patients with extensive necrotic decubitus ulcers or other surgical emergencies should not undergo percutaneous image-guided biopsies but rather should be admitted for surgical debridement and intraoperative cultures. Multidisciplinary discussion and approach are crucial to ensure optimal diagnosis and care of patients diagnosed with chronic osteomyelitis.
View details for DOI 10.1148/radiol.231348
View details for PubMedID 38625010
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ASSOCIATIONS BETWEEN ABDOMINAL ADIPOSE AND MUSCLE TISSUE COMPOSITIONS AND KNEE, HIP, AND SPINE OSTEOARTHRITIS DIAGNOSED PATIENTS: DEEP LEARNING COMPUTED TOMOGRAPHY ANALYSIS IN 14,714 PATIENTS
ELSEVIER SCI LTD. 2024: S199-S200
View details for Web of Science ID 001280544200271
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Body composition measurements and clinical outcomes in patients with resectable pancreatic adenocarcinoma - analysis from SWOG S1505.
Journal of gastrointestinal surgery : official journal of the Society for Surgery of the Alimentary Tract
2024; 28 (3): 232-235
Abstract
BACKGROUND: Sarcopenic obesity and muscle attenuation have been associated with survival in patients with borderline resectable and advanced pancreatic ductal adenocarcinoma (PDA); however, these relationships are unknown for patients with resectable PDA. This study examined the associations between skeletal muscle and adipose tissue as measured on baseline computed tomography (CT) and the overall survival (OS) of participants with resectable PDA in a secondary analysis of the Southwest Oncology Group S1505 clinical trial (identifier: NCT02562716).METHODS: The S1505 phase II clinical trial enrolled patients with resectable PDA who were randomized to receive modified FOLFIRINOX or gemcitabine and nab-paclitaxel as perioperative chemotherapy, followed by surgical resection. Baseline axial CT images at the L3 level were analyzed with externally validated software, and measurements were recorded for skeletal muscle area and skeletal muscle density, visceral adipose tissue area (VATA) and density, and subcutaneous adipose tissue area and density. The relationships between CT metrics and OS were analyzed using Cox regression models, with adjustment for baseline participant characteristics.RESULTS: Of 98 eligible participants with available baseline abdominal CT, 8 were excluded because of imaging quality (eg, orthopedic hardware), resulting in 90 evaluable cases: 51 men (57.0%; mean age, 63.2 years [SD, 8.5]; mean body mass index [BMI], 29.3kg/m2 [SD, 6.4]), 80 White (89.0%), 6 Black (7.0%), and 4 unknown race (4.0%). Sarcopenia was present in 32 participants (35.9%), and sarcopenic obesity was present in 10 participants (11.2%). Univariable analyses for the 6 variables of interest indicated that the standardized mean difference (hazard ratio [HR], 0.75; 95% CI, 0.57-0.98; P=.04) was statistically significantly associated with OS. In models adjusted for sex, race, age, BMI, performance score, contrast use, sarcopenia, and sarcopenic obesity, VATA was statistically significantly associated with OS (HR, 1.58; 95% CI, 1.00-2.51; P=.05). No difference was observed in OS between participants according to sarcopenic obesity or sarcopenia categories. The median OS estimates were 25.1 months for participants without sarcopenic obesity, 18.6 months for participants with sarcopenic obesity, 23.6 months for participants without sarcopenia, and 27.9 months for participants with sarcopenia.CONCLUSION: This was the first study to systematically evaluate body composition parameters in a prospective multicenter trial of patients with resectable PDA who received perioperative chemotherapy. Visceral adipose tissue was associated with survival; however, there was no association between OS and sarcopenia or sarcopenic obesity. Further studies should evaluate these findings in more detail.
View details for DOI 10.1016/j.gassur.2023.12.022
View details for PubMedID 38445914
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Biomarkers of Body Composition.
Seminars in musculoskeletal radiology
2024; 28 (1): 78-91
Abstract
The importance and impact of imaging biomarkers has been increasing over the past few decades. We review the relevant clinical and imaging terminology needed to understand the clinical and research applications of body composition. Imaging biomarkers of bone, muscle, and fat tissues obtained with dual-energy X-ray absorptiometry, computed tomography, magnetic resonance imaging, and ultrasonography are described.
View details for DOI 10.1055/s-0043-1776430
View details for PubMedID 38330972
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Relationships Between Diagnostic Imaging of First Carpometacarpal Osteoarthritis and Pain, Functional Status, and Disease Progression: A Systematic Review.
Osteoarthritis and cartilage
2023
Abstract
To systematically review the association of pain, function, and progression in first carpometacarpal osteoarthritis with imaging biomarkers and radiography-based staging.Database searches in PubMed, Embase, and the Cochrane Library, along with citation searching were conducted in accordance with published guidance. Data on the association of imaging with pain, functional status, and disease progression were extracted and synthesized, along with key information on study methodology such as sample sizes, use of control subjects, study design, number of image raters, and blinding. Methodological quality was assessed using National Heart, Lung, and Blood Institute tools.After duplicate removal, a total of 1,969 records were screened. Forty-six articles are included in this review, covering a total of 28,202 study participants, 7,263 with first carpometacarpal osteoarthritis. Osteophytes were found to be one of the strongest biomarkers for pain across imaging modalities. Radiographic findings alone showed conflicting relationships with pain. However, Kellgren-Lawrence staging showed consistent associations with pain in various studies. Radiographic, sonographic, and MRI findings and staging showed little association to tools evaluating functional status across imaging modalities. The same imaging methods showed limited ability to predict progression of first carpometacarpal osteoarthritis. A major limitation was the heterogeneity in the study base, limiting synthesis of results.Imaging findings and radiography-based staging systems generally showed strong associations with pain, but not with functional status or disease progression. More research and improved imaging techniques are needed to help physicians better manage patients with first carpometacarpal osteoarthritis.
View details for DOI 10.1016/j.joca.2023.11.023
View details for PubMedID 38141842
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Advanced Arthritis of the Carpus: Preoperative Planning Practices of 337 Hand Surgeons.
Journal of wrist surgery
2023; 12 (6): 517-521
Abstract
Background Surgical procedure selection for carpal arthritis depends on which articular surfaces are affected, but there is no consensus on how to preoperatively evaluate cartilage surfaces. Despite advances in cross-sectional imaging, the utility of advanced imaging for preoperative decision-making has not been well established. Objectives Our objective was to assess if there is an added value to presurgical advanced imaging or diagnostic procedures in planning for carpal arthrodesis or carpectomy and to determine what imaging or diagnostic procedures influence surgical treatment options. Methods A seven-question survey was sent to 2,400 hand surgeons. Questions assessed which articular surfaces surgeons consider important for decision-making, which imaging modalities surgeons employ, and how often surgeons utilize diagnostic arthroscopy before performing carpectomy or arthrodesis procedures. Results A total of 337 (14%) surveys were analyzed. The capitolunate articulation (alone or in combination) was most frequently reported to impact surgical decision-making (48.1%). Most surgeons (86.6%) reported that standard plain radiographs are usually sufficient. Few surgeons reported always obtaining magnetic resonance imaging (MRI) or computed tomography (CT), with 44.2% of surgeons believing that MRI is never useful and 38.4% believing that CT is never useful. Most surgeons (68.2%) reported that they never perform wrist arthroscopy as part of their decision-making process. Conclusions This study provides information on the decision-making process in the surgical management of carpal arthritis. Given advances in cross-sectional imaging, further studies are needed to determine the utility of MRI and CT for the planning of surgical procedures in the treatment of arthritis of the carpus. Level of Evidence Level 4.
View details for DOI 10.1055/s-0043-1764302
View details for PubMedID 38213560
View details for PubMedCentralID PMC10781575
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Opportunistic assessment of ischemic heart disease risk using abdominopelvic computed tomography and medical record data: a multimodal explainable artificial intelligence approach.
Scientific reports
2023; 13 (1): 21034
Abstract
Current risk scores using clinical risk factors for predicting ischemic heart disease (IHD) events-the leading cause of global mortality-have known limitations and may be improved by imaging biomarkers. While body composition (BC) imaging biomarkers derived from abdominopelvic computed tomography (CT) correlate with IHD risk, they are impractical to measure manually. Here, in a retrospective cohort of 8139 contrast-enhanced abdominopelvic CT examinations undergoing up to 5 years of follow-up, we developed multimodal opportunistic risk assessment models for IHD by automatically extracting BC features from abdominal CT images and integrating these with features from each patient's electronic medical record (EMR). Our predictive methods match and, in some cases, outperform clinical risk scores currently used in IHD risk assessment. We provide clinical interpretability of our model using a new method of determining tissue-level contributions from CT along with weightings of EMR features contributing to IHD risk. We conclude that such a multimodal approach, which automatically integrates BC biomarkers and EMR data, can enhance IHD risk assessment and aid primary prevention efforts for IHD. To further promote research, we release the Opportunistic L3 Ischemic heart disease (OL3I) dataset, the first public multimodal dataset for opportunistic CT prediction of IHD.
View details for DOI 10.1038/s41598-023-47895-y
View details for PubMedID 38030716
View details for PubMedCentralID 7734661
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Skeletal Muscle Area on CT: Determination of an Optimal Height Scaling Power and Testing for Mortality Risk Prediction.
AJR. American journal of roentgenology
2023
Abstract
BACKGROUND: Sarcopenia is commonly assessed on CT using the skeletal muscle index (SMI), calculated as skeletal muscle area (SMA) at L3 divided by patient height squared (i.e., height scaling power of 2). OBJECTIVE: To determine the optimal height scaling power for SMA measurements on CT, and to test the influence of the derived optimal scaling power on the utility of SMI in predicting all-cause mortality. METHODS: This retrospective study included 16,575 patients (mean age, 56.4 years; 6985 men, 9590 women) who underwent abdominal CT from December 2012 through October 2018. SMA at L3 was determined using automated software. The sample was stratified into 5459 patients without major medical conditions (using ICD-9 and ICD-10 codes) for determining an optimal height scaling power, and 11,116 patients with major medical conditions for testing this power. The optimal scaling power was determined by allometric analysis (whereby regression coefficients were fitted to log-linear sex-specific models relating height to SMA) and by analysis of statistical independence of SMI from height across scaling powers. Cox proportional hazards models were used to test the derived optimal scaling power's influence on utility of SMI in predicting all-cause mortality. RESULTS: In allometric analysis, the regression coefficient of log(height) in patients ≤40 years was 1.02 in men and 1.08 in women, and in patients >40 years was 1.07 in men and 1.10 in women (all p<.05 vs regression coefficient of 2). In analyses for statistical independence of SMI from height, the optimal height scaling power (i.e., those yielding correlations closest to 0) was, in patients ≤40 years, 0.97 in men and 1.08 in women, and in patients >40 years, 1.03 in men and 1.09 in women. In the Cox model used for testing, SMI predicted all-cause mortality with greater concordance index using a height scaling power of 1 than 2 in men (0.675 vs 0.663, p<.001) and women (0.664 vs 0.653, p<.001). CONCLUSION: The findings support a height scaling power of 1, rather than conventional power of 2, for SMI computation. CLINICAL IMPACT: A revised height scaling power for SMI could impact the utility of CT-based sarcopenia diagnoses in risk assessment.
View details for DOI 10.2214/AJR.23.29889
View details for PubMedID 37877596
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Real-Time MRI of the moving wrist at 0.55 tesla.
The British journal of radiology
2023: 20230298
Abstract
OBJECTIVES: Magnetic Resonance Imaging (MRI) using 1.5T or 3.0T systems is routinely employed for assessing wrist pathology, however, due to off-resonance artifacts and high power deposition, these high-field systems have drawbacks for real-time (RT) imaging of the moving wrist. Recently, high-performance 0.55T MRI systems have become available. In this proof-of-concept study we tested the hypothesis that RT-MRI during continuous, active, and uninterrupted wrist motion is feasible with a high-performance 0.55T system at temporal resolutions below 100 ms and that the resulting images provide visualization of tissues commonly interrogated for assessing dynamic wrist instability.METHODS: Participants were scanned during uninterrupted wrist radial-ulnar deviation and clenched fist maneuvers. Resulting images (nominal temporal resolution of 12.7-164.6 ms per image) were assessed for image quality. Feasibility of static MRI to supplement RT-MRI acquisition was also tested.RESULTS: The RT images with temporal resolutions < 100 ms demonstrated low distortion and image artifacts, and higher reader assessment scores. Static MRI scans showed the ability to assess anatomical structures of interest in the wrist.CONCLUSION: RT-MRI of the wrist at a high temporal resolution, coupled with static MRI, is feasible with a high-performance 0.55T system, and may enable improved assessment of wrist dynamic dysfunction and instability.ADVANCES IN KNOWLEDGE: Real-time MRI of the moving wrist is feasible with high-performance 0.55T and may improve the evaluation of dynamic dysfunction of the wrist.
View details for DOI 10.1259/bjr.20230298
View details for PubMedID 37750944
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MRI of patellar stabilizers: Anatomic visibility, inter-reader reliability, and intra-reader reproducibility of primary and secondary ligament anatomy.
Skeletal radiology
2023
Abstract
To compare MRI features of medial and lateral patellar stabilizers in patients with and without patellar instability.Retrospective study of 196 patients (mean age, 33.1 ± 18.5 years; 119 women) after diagnosis of patellar instability (cohort-1, acute patellar dislocation; cohort-2, chronic patellar maltracking) or no patellar instability (cohort-3, acute ACL rupture; cohort-4, chronic medial meniscus tear). On MRI, four medial and four lateral stabilizers were evaluated for visibility and injury by three readers independently. Inter- and intra-reader agreement was determined.Medial and lateral patellofemoral ligaments (MPFL and LPFL) were mostly or fully visualized in all cases (100%). Of the secondary patellar stabilizers, the medial patellotibial ligament was mostly or fully visualized in 166 cases (84.7%). Other secondary stabilizers were mostly or fully visualized in only a minority of cases (range, 0.5-32.1%). Injury scores for all four medial stabilizers were higher in patients with acute patellar dislocation than the other 3 cohorts (p < .05). Visibility inter- and intra-reader agreement was good for medial stabilizers (κ 0.61-0.78) and moderate-to-good for lateral stabilizers (κ 0.40-0.72). Injury inter- and intra-reader agreement was moderate-to-excellent for medial stabilizers (κ 0.43-0.90) and poor-to-moderate for lateral stabilizers (κ 0-0.50).The MPFL and LPFL were well visualized on MRI while the secondary stabilizers were less frequently visualized. The secondary stabilizers were more frequently visualized medially than laterally, and patellotibial ligaments were more frequently visualized compared to the other secondary stabilizers. Injury to the medial stabilizers was more common with acute patellar dislocation than with chronic patellar maltracking or other knee injuries.
View details for DOI 10.1007/s00256-023-04432-2
View details for PubMedID 37704830
View details for PubMedCentralID 7723147
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Clinical, functional, and opportunistic CT metrics of sarcopenia at the point of imaging care: analysis of all-cause mortality.
Skeletal radiology
2023
Abstract
This study examines clinical, functional, and CT metrics of sarcopenia and all-cause mortality in older adults undergoing outpatient imaging.The study included outpatients ≥ 65 years of age undergoing CT or PET/CT at a tertiary care institution. Assessments included screening questionnaires for sarcopenia (SARC-F) and frailty (FRAIL scale), and measurements of grip strength and usual gait speed (6 m course). Skeletal muscle area (SMA), index (SMI, area/height2) and density (SMD) were measured on CT at T12 and L3. A modified SMI was also examined (SMI-m, area/height). Mortality risk was studied with Cox proportional hazard analysis.The study included 416 patients; mean age 73.8 years [sd 6.2]; mean follow-up 2.9 years (sd 1.34). Abnormal grip, SARC-F, and FRAIL scale assessments were associated with higher mortality risk (HR [95%CI] = 2.0 [1.4-2.9], 1.6 [1.1-2.3], 2.0 [1.4-2.8]). Adjusting for age, higher L3-SMA, T12-SMA, T12-SMI and T12-SMI-m were associated with lower mortality risk (HR [95%CI] = 0.80 [0.65-0.90], 0.76 [0.64-0.90], 0.84 [0.70-1.00], and 0.80 [0.67-0.90], respectively). T12-SMD and L3-SMD were not predictive of mortality. After adjusting for abnormal grip strength and FRAIL scale assessments, T12-SMA and T12-SMI-m remained predictive of mortality risk (HR [95%CI] = 0.83 [0.70-1.00] and 0.80 [0.67-0.97], respectively).CT areal metrics were weaker predictors of all-cause mortality than clinical and functional metrics of sarcopenia in our older patient cohort; a CT density metric (SMD) was not predictive. Of areal CT metrics, SMI (area/height2) appeared to be less effective than non-normalized SMA or SMA normalized by height1.
View details for DOI 10.1007/s00256-023-04438-w
View details for PubMedID 37684434
View details for PubMedCentralID 9891989
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Muscle Steatosis and Fibrosis in Older Adults, From the AJR Special Series on Imaging of Fibrosis.
AJR. American journal of roentgenology
2023
Abstract
The purpose of this article is to review steatosis and fibrosis of skeletal muscle, focusing on older adults. Although CT, MRI, and ultrasound are commonly used to image skeletal muscle and provide diagnoses for a variety of medical conditions, quantitative assessment of muscle steatosis and fibrosis is uncommon. This review provides radiologists with a broad perspective on muscle steatosis and fibrosis in older adults by considering their public health impact, biologic mechanisms, and evaluation using CT, MRI, and ultrasound. Promising directions in clinical research that employ artificial intelligence algorithms and the imaging assessment of biologic age are also reviewed. The presented imaging methods hold promise for improving the evaluation of common conditions affecting older adults including sarcopenia, frailty, and cachexia.
View details for DOI 10.2214/AJR.23.29742
View details for PubMedID 37610777
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Association of CT-Derived Skeletal Muscle and Adipose Tissue Metrics with Frailty in Older Adults.
Academic radiology
2023
Abstract
RATIONALE AND OBJECTIVES: Tools are needed for frailty screening of older adults. Opportunistic analysis of body composition could play a role. We aim to determine whether computed tomography (CT)-derived measurements of muscle and adipose tissue are associated with frailty.MATERIALS AND METHODS: Outpatients aged ≥55 years consecutively imaged with contrast-enhanced abdominopelvic CT over a 3-month interval were included. Frailty was determined from the electronic health record using a previously validated electronic frailty index (eFI). CT images at the level of the L3 vertebra were automatically segmented to derive muscle metrics (skeletal muscle area [SMA], skeletal muscle density [SMD], intermuscular adipose tissue [IMAT]) and adipose tissue metrics (visceral adipose tissue [VAT], subcutaneous adipose tissue [SAT]). Distributions of demographic and CT-derived variables were compared between sexes. Sex-specific associations of muscle and adipose tissue metrics with eFI were characterized by linear regressions adjusted for age, race, ethnicity, duration between imaging and eFI measurements, and imaging parameters.RESULTS: The cohort comprised 886 patients (449 women, 437 men, mean age 67.9 years), of whom 382 (43%) met the criteria for pre-frailty (ie, 0.10< eFI ≤ 0.21) and 138 (16%) for frailty (eFI > 0.21). In men, 1 standard deviation changes in SMD (beta = -0.01, 95% confidence interval [CI],-0.02 to-0.001, P=.02) and VAT area (beta = 0.008, 95% CI,0.0005-0.02, P=.04), but not SMA, IMAT, or SAT, were associated with higher frailty. In women, none of the CT-derived muscle or adipose tissue metrics were associated with frailty.CONCLUSION: We observed a positive association between frailty and CT-derived biomarkers of myosteatosis and visceral adiposity in a sex-dependent manner.
View details for DOI 10.1016/j.acra.2023.06.003
View details for PubMedID 37479618
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Noise2Recon: Enabling SNR-robust MRI reconstruction with semi-supervised and self-supervised learning.
Magnetic resonance in medicine
2023
Abstract
PURPOSE: To develop a method for building MRI reconstruction neural networks robust to changes in signal-to-noise ratio (SNR) and trainable with a limited number of fully sampled scans.METHODS: We propose Noise2Recon, a consistency training method for SNR-robust accelerated MRI reconstruction that can use both fully sampled (labeled) and undersampled (unlabeled) scans. Noise2Recon uses unlabeled data by enforcing consistency between model reconstructions of undersampled scans and their noise-augmented counterparts. Noise2Recon was compared to compressed sensing and both supervised and self-supervised deep learning baselines. Experiments were conducted using retrospectively accelerated data from the mridata three-dimensional fast-spin-echo knee and two-dimensional fastMRI brain datasets. All methods were evaluated in label-limited settings and among out-of-distribution (OOD) shifts, including changes in SNR, acceleration factors, and datasets. An extensive ablation study was conducted to characterize the sensitivity of Noise2Recon to hyperparameter choices.RESULTS: In label-limited settings, Noise2Recon achieved better structural similarity, peak signal-to-noise ratio, and normalized-RMS error than all baselines and matched performance of supervised models, which were trained with 14 * $$ 14\times $$ more fully sampled scans. Noise2Recon outperformed all baselines, including state-of-the-art fine-tuning and augmentation techniques, among low-SNR scans and when generalizing to OOD acceleration factors. Augmentation extent and loss weighting hyperparameters had negligible impact on Noise2Recon compared to supervised methods, which may indicate increased training stability.CONCLUSION: Noise2Recon is a label-efficient reconstruction method that is robust to distribution shifts, such as changes in SNR, acceleration factors, and others, with limited or no fully sampled training data.
View details for DOI 10.1002/mrm.29759
View details for PubMedID 37427449
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Knee MRI: Meniscus Roots, Ramps, Repairs, and Repercussions.
Radiographics : a review publication of the Radiological Society of North America, Inc
2023; 43 (7): e220208
Abstract
Menisci play an essential role in maintaining normal pain-free function of the knee. While there are decades of MRI literature on the tears involving the meniscus body and horns, there is now a surge in knowledge regarding injuries at the meniscus roots and periphery. The authors briefly highlight new insights into meniscus anatomy and then summarize recent developments in the understanding of meniscus injuries that matter, emphasizing meniscus injuries at the root and peripheral (eg, ramp) regions that may be missed easily at MRI and arthroscopy. Root and ramp tears are important to diagnose because they may be amenable to repair. However, if these tears are left untreated, ongoing pain and accelerated cartilage degeneration may ensue. The posterior roots of the medial and lateral menisci are most commonly affected by injury, and each of these injuries is associated with distinctive clinical profiles, MRI findings, and tear patterns. Specific diagnostic pitfalls can make the roots challenging to evaluate, including MRI artifacts and anatomic variations. As with root tears, MRI interpretation and orthopedic treatment have important differences for injuries at the medial versus lateral meniscus (LM) periphery (located at or near the meniscocapsular junction). Medially, ramp lesions typically occur in the setting of an anterior cruciate ligament rupture and are generally classified into five patterns. Laterally, the meniscocapsular junction may be injured in association with tibial plateau fractures, but disruption of the popliteomeniscal fascicles may also result in a hypermobile LM. Updated knowledge of the meniscus root and ramp tears is crucial in optimizing diagnostic imaging before repair and understanding the clinical repercussions. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available in the Online Learning Center.
View details for DOI 10.1148/rg.220208
View details for PubMedID 37384542
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Fast volumetric ultrasound facilitates high-resolution 3D mapping of tissue compartments.
Science advances
2023; 9 (22): eadg8176
Abstract
Volumetric ultrasound imaging has the potential for operator-independent acquisition and enhanced field of view. Panoramic acquisition has many applications across ultrasound; spanning musculoskeletal, liver, breast, and pediatric imaging; and image-guided therapy. Challenges in high-resolution human imaging, such as subtle motion and the presence of bone or gas, have limited such acquisition. These issues can be addressed with a large transducer aperture and fast acquisition and processing. Programmable, ultrafast ultrasound scanners with a high channel count provide an unprecedented opportunity to optimize volumetric acquisition. In this work, we implement nonlinear processing and develop distributed beamformation to achieve fast acquisition over a 47-centimeter aperture. As a result, we achieve a 50-micrometer -6-decibel point spread function at 5 megahertz and resolve in-plane targets. A large volume scan of a human limb is completed in a few seconds, and in a 2-millimeter dorsal vein, the image intensity difference between the vessel center and surrounding tissue was ~50 decibels, facilitating three-dimensional reconstruction of the vasculature.
View details for DOI 10.1126/sciadv.adg8176
View details for PubMedID 37256942
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Patellar Tracking: An Old Problem with New Insights.
Radiographics : a review publication of the Radiological Society of North America, Inc
2023; 43 (6): e220177
Abstract
Patellofemoral pain and instability are common indications for imaging that are encountered in everyday practice. The authors comprehensively review key aspects of patellofemoral instability pertinent to radiologists that can be seen before the onset of osteoarthritis, highlighting the anatomy, clinical evaluation, diagnostic imaging, and treatment. Regarding the anatomy, the medial patellofemoral ligament (MPFL) is the primary static soft-tissue restraint to lateral patellar displacement and is commonly reconstructed surgically in patients with MPFL dysfunction and patellar instability. Osteoarticular abnormalities that predispose individuals to patellar instability include patellar malalignment, trochlear dysplasia, and tibial tubercle lateralization. Clinically, patients with patellar instability may be divided into two broad groups with imaging findings that sometimes overlap: patients with a history of overt patellar instability after a traumatic event (eg, dislocation, subluxation) and patients without such a history. In terms of imaging, radiography is generally the initial examination of choice, and MRI is the most common cross-sectional examination performed preoperatively. For all imaging techniques, there has been a proliferation of published radiologic measurement methods. The authors summarize the most common validated measurements for patellar malalignment, trochlear dysplasia, and tibial tubercle lateralization. Given that static imaging is inherently limited in the evaluation of patellar motion, dynamic imaging with US, CT, or MRI may be requested by some surgeons. The primary treatment strategy for patellofemoral pain is conservative. Surgical treatment options include MPFL reconstruction with or without osseous corrections such as trochleoplasty and tibial tubercle osteotomy. Postoperative complications evaluated at imaging include patellar fracture, graft failure, graft malposition, and medial patellar subluxation. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.
View details for DOI 10.1148/rg.220177
View details for PubMedID 37261964
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Interdisciplinary consensus statements on imaging of DRUJ instability and TFCC injuries.
European radiology
2023
Abstract
The purpose of this agreement was to establish evidence-based consensus statements on imaging of distal radioulnar joint (DRUJ) instability and triangular fibrocartilage complex (TFCC) injuries by an expert group using the Delphi technique.Nineteen hand surgeons developed a preliminary list of questions on DRUJ instability and TFCC injuries. Radiologists created statements based on the literature and the authors' clinical experience. Questions and statements were revised during three iterative Delphi rounds. Delphi panelists consisted of twenty-seven musculoskeletal radiologists. The panelists scored their degree of agreement to each statement on an 11-item numeric scale. Scores of "0," "5," and "10" reflected complete disagreement, indeterminate agreement, and complete agreement, respectively. Group consensus was defined as a score of "8" or higher for 80% or more of the panelists.Three of fourteen statements achieved group consensus in the first Delphi round and ten statements achieved group consensus in the second Delphi round. The third and final Delphi round was limited to the one question that did not achieve group consensus in the previous rounds.Delphi-based agreements suggest that CT with static axial slices in neutral rotation, pronation, and supination is the most useful and accurate imaging technique for the work-up of DRUJ instability. MRI is the most valuable technique in the diagnosis of TFCC lesions. The main indication for MR arthrography and CT arthrography are Palmer 1B foveal lesions of the TFCC.MRI is the method of choice for assessing TFCC lesions, with higher accuracy for central than peripheral abnormalities. The main indication for MR arthrography is the evaluation of TFCC foveal insertion lesions and peripheral non-Palmer injuries.• Conventional radiography should be the initial imaging technique in the assessment of DRUJ instability. CT with static axial slices in neutral rotation, pronation, and supination is the most accurate method for evaluating DRUJ instability. • MRI is the most useful technique in diagnosing soft-tissue injuries causing DRUJ instability, especially TFCC lesions. • The main indications for MR arthrography and CT arthrography are foveal lesions of the TFCC.
View details for DOI 10.1007/s00330-023-09698-7
View details for PubMedID 37191922
View details for PubMedCentralID 6005773
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The GIANT trial (ECOG-ACRIN EA2186) methods paper: A randomized phase II study of gemcitabine and nab-paclitaxel compared with 5-fluorouracil, leucovorin, and liposomal irinotecan in older patients with treatment-naïve metastatic pancreatic cancer - defining a new treatment option for older vulnerable patients.
Journal of geriatric oncology
2023; 14 (3): 101474
Abstract
Pancreatic cancer is the fourth leading cause of cancer-related death in the US with an increasing incidence in older adults (OA) over age 70. There are currently no treatment guidelines for OA with metastatic pancreatic cancer (mPCA) and selecting a chemotherapy regimen for these patients is subjective, based largely on chronologic age and performance status (PS). Geriatric screening tools provide a more objective and accurate evaluation of a patient's overall health but have not yet been validated in patient selection for mPCA treatment. This study aims to elucidate the optimal chemotherapy treatment of vulnerable OA with mPCA and understand the geriatric factors that affect outcomes in this population.The GIANT (ECOG-ACRIN EA2186) study is multicenter, randomized phase II trial enrolling patients over age 70 with newly diagnosed mPCA. This study utilizes a screening geriatric assessment (GA) which characterizes patients as fit, vulnerable, or frail. Patients with mild abnormalities in functional status and/or cognition, moderate comorbidities, or over age 80 are considered vulnerable. Enrolled patients are randomized to one of two dose-reduced treatment regimens (gemcitabine/nab-paclitaxel every other week, or dose-reduced 5-fluoruracil (5FU)/ liposomal irinotecan (nal-IRI) every other week). GA and quality of life (QoL) evaluations are completed prior to treatment initiation and at each disease evaluation. Overall survival (OS) is the primary endpoint, with secondary endpoints including progression free survival (PFS) and objective response rate (ORR). Enrolled patients will be stratified by age (70-74 vs ≥75) and ECOG PS (0-1 vs 2). Additional endpoints of interest for OA include evaluation of risk factors identified through GA, QoL evaluation, and toxicities of interest for older adults. Correlative studies include assessment of pro-inflammatory biomarkers of aging in the blood (IL-6, CRP) and imaging evaluation of sarcopenia as predictors of treatment tolerance.The GIANT study is the first randomized, prospective national trial evaluating vulnerable OA with mPCA aimed at developing a tailored treatment approach for this patient population. This trial has the potential to establish a new way of objectively selecting vulnerable OA with mPCA for modified treatment and to establish a new standard of care in this growing patient population.This trial is registered with ClinicalTrial.gov Identifier NCT04233866.
View details for DOI 10.1016/j.jgo.2023.101474
View details for PubMedID 36963200
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Editorial Comment: Death and Taxes…and Artificial Intelligence.
AJR. American journal of roentgenology
2023
Abstract
This Editorial Comment discusses the following AJR article: Technical Adequacy of Fully Automated Artificial Intelligence Body Composition Tools: Assessment in a Heterogeneous Sample of External CT Examinations.
View details for DOI 10.2214/AJR.23.29228
View details for PubMedID 37095676
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Improving Data-Efficiency and Robustness of Medical Imaging Segmentation Using Inpainting-Based Self-Supervised Learning.
Bioengineering (Basel, Switzerland)
2023; 10 (2)
Abstract
We systematically evaluate the training methodology and efficacy of two inpainting-based pretext tasks of context prediction and context restoration for medical image segmentation using self-supervised learning (SSL). Multiple versions of self-supervised U-Net models were trained to segment MRI and CT datasets, each using a different combination of design choices and pretext tasks to determine the effect of these design choices on segmentation performance. The optimal design choices were used to train SSL models that were then compared with baseline supervised models for computing clinically-relevant metrics in label-limited scenarios. We observed that SSL pretraining with context restoration using 32 × 32 patches and Poission-disc sampling, transferring only the pretrained encoder weights, and fine-tuning immediately with an initial learning rate of 1 × 10-3 provided the most benefit over supervised learning for MRI and CT tissue segmentation accuracy (p < 0.001). For both datasets and most label-limited scenarios, scaling the size of unlabeled pretraining data resulted in improved segmentation performance. SSL models pretrained with this amount of data outperformed baseline supervised models in the computation of clinically-relevant metrics, especially when the performance of supervised learning was low. Our results demonstrate that SSL pretraining using inpainting-based pretext tasks can help increase the robustness of models in label-limited scenarios and reduce worst-case errors that occur with supervised learning.
View details for DOI 10.3390/bioengineering10020207
View details for PubMedID 36829701
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Ageism in Society and Its Health Impact.
AJR. American journal of roentgenology
2023
Abstract
Ageism is an increasingly recognized form of cognitive bias involving stereotypes, prejudice, and discrimination directed toward people based on their age. Age-based bias influences how medicine is practiced and can result in profoundly negative but avoidable health outcomes. Awareness and education regarding ageism and its manifestations can improve the ability to identify and mitigate ageism. As this Viewpoint describes, radiologists are well situated to be part of the solution in addressing ageism.
View details for DOI 10.2214/AJR.22.28748
View details for PubMedID 36722760
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Pre-operative imaging for surgical decision-making and the frequency of wrist arthrodesis and carpectomy procedures: a scoping review.
Skeletal radiology
2022
Abstract
OBJECTIVES: Our objectives were to (1) analyze the imaging modalities utilized pre-operatively that influence surgical decision-making for wrist arthrodesis and carpectomy procedures and (2) determine the type and frequency of these procedures for the treatment of wrist arthritis.MATERIALS AND METHODS: This review was performed according to the guidelines of PRISMA Extension for Scoping Reviews. Using PubMed, Embase, and Scopus, peer-reviewed literature from 2011 to 2022 was searched for use of imaging in pre-operative decision-making for wrist arthrodesis and carpectomy surgical procedures. Data were compiled to determine the type(s) of imaging modalities used pre-operatively and types of surgical techniques reported in the literature.RESULTS: Of 307 articles identified, 35 articles satisfied eligibility criteria, with a total of 1377 patients (68% men; age mean, 50.9years [range, 10-81]) and 1428 wrist surgical interventions. Radiography was reported for pre-operative planning in all articles for all patients. Pre-operative cross-sectional imaging was reported in 2 articles (5.7%), but no articles reported detailed data on how CT or MRI influenced pre-operative wrist arthrodesis and carpectomy procedure decision-making. A dozen different types of surgical techniques were reported. The four most common procedures were four-corner arthrodesis with scaphoid excision (846, 59%), proximal row carpectomy (239, 17%), total wrist arthrodesis (130, 9%), and scaphocapitate arthrodesis (53, 4%).CONCLUSION: Radiography is always used in pre-operative decision-making, but the literature lacks data on the influence of CT and MRI for selecting among a dozen different types of wrist arthrodesis and carpectomy procedures.
View details for DOI 10.1007/s00256-022-04157-8
View details for PubMedID 35970955
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Generalizability of Deep Learning Segmentation Algorithms for Automated Assessment of Cartilage Morphology and MRI Relaxometry.
Journal of magnetic resonance imaging : JMRI
2022
Abstract
BACKGROUND: Deep learning (DL)-based automatic segmentation models can expedite manual segmentation yet require resource-intensive fine-tuning before deployment on new datasets. The generalizability of DL methods to new datasets without fine-tuning is not well characterized.PURPOSE: Evaluate the generalizability of DL-based models by deploying pretrained models on independent datasets varying by MR scanner, acquisition parameters, and subject population.STUDY TYPE: Retrospective based on prospectively acquired data.POPULATION: Overall test dataset: 59 subjects (26 females); Study 1: 5 healthy subjects (zero females), Study 2: 8 healthy subjects (eight females), Study 3: 10 subjects with osteoarthritis (eight females), Study 4: 36 subjects with various knee pathology (10 females).FIELD STRENGTH/SEQUENCE: A 3-T, quantitative double-echo steady state (qDESS).ASSESSMENT: Four annotators manually segmented knee cartilage. Each reader segmented one of four qDESS datasets in the test dataset. Two DL models, one trained on qDESS data and another on Osteoarthritis Initiative (OAI)-DESS data, were assessed. Manual and automatic segmentations were compared by quantifying variations in segmentation accuracy, volume, and T2 relaxation times for superficial and deep cartilage.STATISTICAL TESTS: Dice similarity coefficient (DSC) for segmentation accuracy. Lin's concordance correlation coefficient (CCC), Wilcoxon rank-sum tests, root-mean-squared error-coefficient-of-variation to quantify manual vs. automatic T2 and volume variations. Bland-Altman plots for manual vs. automatic T2 agreement. A P value<0.05 was considered statistically significant.RESULTS: DSCs for the qDESS-trained model, 0.79-0.93, were higher than those for the OAI-DESS-trained model, 0.59-0.79. T2 and volume CCCs for the qDESS-trained model, 0.75-0.98 and 0.47-0.95, were higher than respective CCCs for the OAI-DESS-trained model, 0.35-0.90 and 0.13-0.84. Bland-Altman 95% limits of agreement for superficial and deep cartilage T2 were lower for the qDESS-trained model, ±2.4msec and ±4.0msec, than the OAI-DESS-trained model, ±4.4msec and ±5.2msec.DATA CONCLUSION: The qDESS-trained model may generalize well to independent qDESS datasets regardless of MR scanner, acquisition parameters, and subject population.EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 1.
View details for DOI 10.1002/jmri.28365
View details for PubMedID 35852498
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Artificial Intelligence System for Automatic Quantitative Analysis and Radiology Reporting of Leg Length Radiographs.
Journal of digital imaging
2022
Abstract
Leg length discrepancies are common orthopedic problems with the potential for poor functional outcomes. These are frequently assessed using bilateral leg length radiographs. The objective was to determine whether an artificial intelligence (AI)-based image analysis system can accurately interpret long leg length radiographic images. We built an end-to-end system to analyze leg length radiographs and generate reports like radiologists, which involves measurement of lengths (femur, tibia, entire leg) and angles (mechanical axis and pelvic tilt), describes presence and location of orthopedic hardware, and reports laterality discrepancies. After IRB approval, a dataset of 1,726 extremities (863 images) from consecutive examinations at a tertiary referral center was retrospectively acquired and partitioned into train/validation and test sets. The training set was annotated and used to train a fasterRCNN-ResNet101 object detection convolutional neural network. A second-stage classifier using a EfficientNet-D0 model was trained to recognize the presence or absence of hardware within extracted joint image patches. The system was deployed in a custom web application that generated a preliminary radiology report. Performance of the system was evaluated using a holdout 220 image test set, annotated by 3 musculoskeletal fellowship trained radiologists. At the object detection level, the system demonstrated a recall of 0.98 and precision of 0.96 in detecting anatomic landmarks. Correlation coefficients between radiologist and AI-generated measurements for femur, tibia, and whole-leg lengths were>0.99, with mean error of<1%. Correlation coefficients for mechanical axis angle and pelvic tilt were 0.98 and 0.86, respectively, with mean absolute error of<1°. AI hardware detection demonstrated an accuracy of 99.8%. Automatic quantitative and qualitative analysis of leg length radiographs using deep learning is feasible and holds potential in improving radiologist workflow.
View details for DOI 10.1007/s10278-022-00671-2
View details for PubMedID 35794502
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Imaging of Sarcopenia.
Radiologic clinics of North America
2022; 60 (4): 575-582
Abstract
Sarcopenia is currently underdiagnosed and undertreated, but this is expected to change because sarcopenia is now recognized with a specific diagnosis code that can be used for billing in some countries, as well as an expanding body of research on prevention, diagnosis, and management. This article focuses on practical issues of increasing interest by highlighting 3 hot topics fundamental to understanding sarcopenia in older adults: definitions and terminology, current diagnostic imaging techniques, and the emerging role of opportunistic computed tomography.
View details for DOI 10.1016/j.rcl.2022.03.001
View details for PubMedID 35672090
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A randomized phase II study of gemcitabine and nab-paclitaxel compared with 5-fluorouracil, leucovorin, and liposomal irinotecan in older patients with treatmentnaive metastatic pancreatic cancer (GIANT): ECOG-ACRIN EA2186-Trials in progress
LIPPINCOTT WILLIAMS & WILKINS. 2022
View details for Web of Science ID 000863680304938
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Ultrasound Identifies First Rib Stress Fractures: A Case Series in Division I Athletes.
Journal of athletic training
2022
Abstract
Isolated first rib stress fractures in athletes are thought to be rare. In this case series, three Division I athletes developed isolated first rib stress fractures over the span of one year, revealing that these may occur more often than previously understood. These fractures can be easily missed because of low incidence, lack of clinical suspicion, and vague presentation. Further, radiographs can fail to reveal such fractures. To our knowledge, this is the largest case series of athletes with first rib stress fractures presenting with vague rhomboid interscapular pain. We also demonstrate that ultrasound successfully visualizes these fractures, thus offering, in the hands of an ultrasonographer or clinical provider trained in musculoskeletal ultrasound, an advantageous point-of-care screening imaging modality.
View details for DOI 10.4085/1062-6050-0375.21
View details for PubMedID 35622951
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MR Imaging of Benign Soft Tissue Tumors: Highlights for the Practicing Radiologist.
Radiologic clinics of North America
2022; 60 (2): 263-281
Abstract
The overwhelming majority of soft tissue masses encountered on routine imaging are incidental and benign. When incidental, the radiologist is usually limited to routine MR imaging sequences, often without contrast. In these situations, there are typical imaging features pointing to a single diagnosis or limited differential diagnosis. Although these imaging features can be helpful, many lesions are nonspecific and may require contrast administration, evaluation with other imaging modalities, follow-up imaging, or biopsy for diagnosis. This article will provide an overview of the most commonly encountered benign soft tissue masses along with some of their characteristic MR imaging features.
View details for DOI 10.1016/j.rcl.2021.11.006
View details for PubMedID 35236593
- Sarcopenia in Rheumatic Disorders: What the Radiologist and Rheumatologist Should Know Skeletal Radiology. 2022
- Charges for Shoppable Musculoskeletal Imaging Examinations: CMS Transparency Compliance and Variability Among 250 U.S. Hospitals. American Journal of Roentgenology (AJR). 2022
- The Global Reading Room: Knee MRI Protocols. American Journal of Roentgenology (AJR). 2022
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Opportunistic Incidence Prediction of Multiple Chronic Diseases from Abdominal CT Imaging Using Multi-task Learning
SPRINGER INTERNATIONAL PUBLISHING AG. 2022: 309-318
View details for DOI 10.1007/978-3-031-16449-1_30
View details for Web of Science ID 000867568000030
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Feasibility of dual-phase 99mTc-MDP SPECT/CT imaging in rheumatoid arthritis evaluation.
Quantitative imaging in medicine and surgery
2021; 11 (6): 2333-2343
Abstract
To prospectively demonstrate the feasibility of performing dual-phase SPECT/CT for the assessment of the small joints of the hands of rheumatoid arthritis (RA) patients, and to evaluate the reliability of the quantitative and qualitative measures derived from the resulting images.A SPECT/CT imaging protocol was developed in this pilot study to scan both hands simultaneously in participants with RA, in two phases of 99mTc-MDP radiotracer uptake, namely the soft-tissue blood pool phase (within 15 minutes after radiotracer injection) and osseous phase (after 3 hours). Joints were evaluated qualitatively (normal vs. abnormal uptake) and quantitatively [by measuring a newly developed metric, maximum corrected count ratio (MCCR)]. Qualitative and quantitative evaluations were repeated to assess reliability.Four participants completed seven studies (all four were imaged at baseline, and three of them at follow-up after 1-month of arthritis therapy). A total of 280 joints (20 per hand) were evaluated. The MCCR from soft-tissue phase scans was significantly higher for clinically abnormal joints compared to clinically normal ones; P<0.001, however the MCCR from the osseous phase scans were not different between the two joint groups. Intraclass Correlation Coefficient (ICC) for MCCR was excellent [0.9789, 95% confidence interval (CI): 0.9734-0.9833]. Intra-observer agreement for qualitative SPECT findings was substantial for both the soft-tissue phase (kappa =0.78, 95% CI: 0.72-0.83) and osseous-phase (kappa =0.70, 95% CI: 0.64-0.76) scans.Extracting reliable quantitative and qualitative measures from dual-phase 99mTc-MDP SPECT/CT hand scans is feasible in RA patients. SPECT/CT may provide a unique means for assessing both synovitis and osseous involvement in RA joints using the same radiotracer injection.
View details for DOI 10.21037/qims-20-996
View details for PubMedID 34079705
View details for PubMedCentralID PMC8107345
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Rapidly progressive idiopathic arthritis of the hip: incidence and risk factors in a controlled cohort study of 1471 patients after intra-articular corticosteroid injection
SKELETAL RADIOLOGY
2021
Abstract
Rapidly progressive idiopathic arthritis of the hip (RPIA) is defined by progressive joint space narrowing of > 2 mm or > 50% within 1 year. Our aims were to assess (a) the occurrence of RPIA after intra-articular steroid injection, and (b) possible risk factors for RPIA including: patient age, BMI, joint space narrowing, anesthetic and steroid selections, bone mineral density, and pain reduction after injection.A retrospective search of our imaging database identified 1471 patients who had undergone fluoroscopically guided hip injection of triamcinolone acetonide (Kenalog) and anesthetic within a 10-year period. Patient data, including hip DXA results and patient-reported pain scores, were recorded. Pre-injection and follow-up radiographs were assessed for joint space narrowing, femoral head deformity, and markers of osteoarthritis. Osteoarthritis was graded by Croft score. Associations between patient characteristics and outcome variables were analyzed.One hundred six of 1471 injected subjects (7.2%) met the criteria for RPIA. A control group of 161 subjects was randomly selected from subjects who underwent hip injections without developing RPIA. Compared to controls, patients with RPIA were older, had narrower hip joint spaces, and higher Croft scores before injection (p < 0.05). Patients who developed RPIA did not differ from controls in sex, BMI, hip DXA T-score, anesthetic and steroid injectates, or pain improvement after injection.We found that approximately 7% of patients undergoing steroid hip injection developed RPIA. More advanced patient age, greater joint space narrowing, and more severe osteoarthritis are risk factors for the development of RPIA after intra-articular steroid injection.
View details for DOI 10.1007/s00256-021-03815-7
View details for Web of Science ID 000652430200002
View details for PubMedID 34018006
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Body composition measurements and overall survival in patients with resectable pancreatic adenocarcinoma receiving neoadjuvant chemotherapy: Analysis from SWOG S1505.
LIPPINCOTT WILLIAMS & WILKINS. 2021
View details for DOI 10.1200/JCO.2021.39.15_suppl.4131
View details for Web of Science ID 000708120602231
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Assessment of Myofascial Trigger Points via Imaging: A Systematic Review.
American journal of physical medicine & rehabilitation
2021
Abstract
ABSTRACT: This study systematically reviewed the published literature on the objective characterization of myofascial pain syndrome and myofascial trigger points using imaging methods. PubMed, Embase, Ovid and the Cochrane Library databases were utilized, while citation searching was conducted in Scopus. Citations were restricted to those published in English and in peer-reviewed journals between 2000-2021. Out of 1,762 abstracts screened, 69 articles underwent full-text review and 33 were included. Imaging data assessing myofascial trigger points (MTrPs) or myofascial pain syndrome (MPS) were extracted and important qualitative and quantitative information on general study methodologies, study populations, sample sizes, and MTrP/MPS evaluation were tabulated. Methodological quality of eligible studies was assessed based on the QUADAS (Quality Assessment of Diagnostic Accuracy Studies) criteria. Biomechanical properties and blood flow of active and latent MTrPs assessed via imaging were found to be quantifiably distinct from those of healthy tissue. While these studies show promise, more studies are needed. Future studies should focus on assessing diagnostic test accuracy and testing the reproducibility of results to establish the best performing methods. Increasing methodological consistency would further motivate implementing imaging methods in larger clinical studies. Considering the evidence on efficacy, cost, ease of use and time constraints, US-based methods are currently the imaging modalities of choice for MPS/MTrP assessment.
View details for DOI 10.1097/PHM.0000000000001789
View details for PubMedID 33990485
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Displaced Flap Tears of the Triangular Fibrocartilage Complex: Frequency, Flap Location, and the "Comma" Sign on Wrist MRI.
AJR. American journal of roentgenology
2021
Abstract
The purpose of this article is to estimate the frequency of displaced triangular fibrocartilage complex (TFCC) tears and to describe their MRI characteristics. A total of 3,411 wrist MRI examinations were assessed, demonstrating 20 displaced TFCC tears in 17 patients (frequency, 0.5%). These flaps were characteristically connected to the TFCC via a pedicle ("comma" sign in 19/20) and displaced into the distal radioulnar joint (19/20). Management implications are considered.
View details for DOI 10.2214/AJR.20.25437
View details for PubMedID 33594905
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Interdisciplinary consensus statements on imaging of scapholunate joint instability.
European radiology
2021
Abstract
The purpose of this agreement was to establish evidence-based consensus statements on imaging of scapholunate joint (SLJ) instability by an expert group using the Delphi technique.Nineteen hand surgeons developed a preliminary list of questions on SLJ instability. Radiologists created statements based on the literature and the authors' clinical experience. Questions and statements were revised during three iterative Delphi rounds. Delphi panellists consisted of twenty-seven musculoskeletal radiologists. The panellists scored their degree of agreement to each statement on an eleven-item numeric scale. Scores of '0', '5' and '10' reflected complete disagreement, indeterminate agreement and complete agreement, respectively. Group consensus was defined as a score of '8' or higher for 80% or more of the panellists.Ten of fifteen statements achieved group consensus in the second Delphi round. The remaining five statements achieved group consensus in the third Delphi round. It was agreed that dorsopalmar and lateral radiographs should be acquired as routine imaging work-up in patients with suspected SLJ instability. Radiographic stress views and dynamic fluoroscopy allow accurate diagnosis of dynamic SLJ instability. MR arthrography and CT arthrography are accurate for detecting scapholunate interosseous ligament tears and articular cartilage defects. Ultrasonography and MRI can delineate most extrinsic carpal ligaments, although validated scientific evidence on accurate differentiation between partially or completely torn or incompetent ligaments is not available.Delphi-based agreements suggest that standardized radiographs, radiographic stress views, dynamic fluoroscopy, MR arthrography and CT arthrography are the most useful and accurate imaging techniques for the work-up of SLJ instability.• Dorsopalmar and lateral wrist radiographs remain the basic imaging modality for routine imaging work-up in patients with suspected scapholunate joint instability. • Radiographic stress views and dynamic fluoroscopy of the wrist allow accurate diagnosis of dynamic scapholunate joint instability. • Wrist MR arthrography and CT arthrography are accurate for determination of scapholunate interosseous ligament tears and cartilage defects.
View details for DOI 10.1007/s00330-021-08073-8
View details for PubMedID 34100996
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Genetic Algorithm based L4 Identification and Psoas Segmentation
SCITEPRESS. 2021: 120-127
View details for DOI 10.5220/0010207701200127
View details for Web of Science ID 000668127000010
- Pelvis and Groin: Practical Anatomy, Injury Patterns, and Imaging Findings Musculoskeletal Diseases 2021-2024: Diagnostic Imaging Springer. 2021
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Reply to "Sarcopenia and Osteoporosis: A Practical Approach to Obtaining Valuable Information With CT".
AJR. American journal of roentgenology
2021: W1
View details for DOI 10.2214/AJR.20.25316
View details for PubMedID 33760652
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Diagnosing sarcopenia at the point of imaging care: analysis of clinical, functional, and opportunistic CT metrics.
Skeletal radiology
2020
Abstract
OBJECTIVE: To determine the relationship between CT-derived muscle metrics and standardized metrics of sarcopenia in patients undergoing routine CT imaging.MATERIALS AND METHODS: Data collected in 443 consecutive patients included body CT, grip strength, usual gait speed, and responses to SARC-F and FRAIL scale questionnaires. Functional and clinical metrics of sarcopenia were acquired at the time of CT. Metrics were analyzed using the diagnostic framework of the European Working Group on Sarcopenia in Older People (EWGSOP2). The skeletal muscle index (SMI) and skeletal muscle density (SMD) were measured at the T12 and L3 levels. Statistical methods include linear prediction models and ROC analysis.RESULTS: T12-SMD and L3-SMD in women and T12-SMD and L3-SMI in men show weak but significant (p<0.05) predictive value for gait speed, after adjusting for subject age and body mass index. The prevalence of abnormal CT SMI at T12 and L3 was 29% and 71%, respectively, corresponding to prevalences of confirmed sarcopenia by EWGSOP2 of 10% and 15%, respectively. The agreement of abnormal SARC-F and FRAIL scale screening and EWGSOP2 confirmed sarcopenia was slight to fair (kappa: 0.20-0.28). CT cutpoints, based on EWGSOP2 criteria for abnormal grip strength or gait speed, are generally lower than cutpoints based on normative population data.CONCLUSION: Collection of clinical and functional sarcopenia information at the point of imaging care can be accomplished quickly and safely. CT-derived muscle metrics show convergent validity with gait speed. Only a minority of subjects with low CT metrics have confirmed sarcopenia by EWGSOP2 definition.
View details for DOI 10.1007/s00256-020-03576-9
View details for PubMedID 32892227
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Computed Tomography (CT) Measurements of Sarcopenia Predict Length of Stay in Older Burn Patients.
Journal of burn care & research : official publication of the American Burn Association
2020
Abstract
INTRODUCTION: Sarcopenia and frailty are associated with aging. In older burn patients, frailty has been associated with mortality and discharge disposition, but sarcopenia has not been examined. This study aims to investigate the relationship between frailty and CT-derived sarcopenia with length of stay and mortality in older burn patients.METHODS: Burn patients ≥60 years old admitted between 2008-2017 who had chest or abdomen CT scans within one week of admission were evaluated. Frailty was assessed using the Canadian Study of Health and Aging Clinical Frailty Scale (CFS). Sarcopenia was assessed on CT exams by measuring skeletal muscle index (SMI) of paraspinal muscles at T12 and all skeletal muscles at L3. The relationship between frailty scores and SMI with length of stay (LOS) and mortality was determined using logistic regression.RESULTS: 83 patients (59 men; mean age 70.2±8.5 years) had chest (n=50) or abdomen (n=60) CT scans. Mean TBSA = 14.3±14.0%, LOS = 25.8±21.3 days, CFS = 4.36±0.99. Sixteen patients (19.3%) died while in the hospital. CT-derived measurement of SMI at T12 was significantly associated with LOS (p&0.05), but not with mortality (p=0.561). CT-derived metrics at L3 were not significantly associated with outcomes. CFS was not associated with LOS (p = 0.836) or mortality (p=0.554).CONCLUSIONS: In older burn patients, low SMI of the paraspinal muscles at T12 was associated with longer LOS.
View details for DOI 10.1093/jbcr/iraa149
View details for PubMedID 32841333
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Soft tissue pathology for the radiologist: a tumor board primer with 2020 WHO classification update.
Skeletal radiology
2020
Abstract
Radiologists serve an important role in the diagnosis and staging of soft tissue tumors, often through participation in multidisciplinary tumor board teams. While an important function of the radiologist is to review pertinent imaging and assist in the differential diagnosis, a critical role is to ensure that there is concordance between the imaging and the pathologic diagnosis. This requires a basic understanding of the pathology of soft tissue tumors, particularly in the case of diagnostic dilemmas or incongruent imaging and histologic features. This work is intended to provide an overview of soft tissue pathology for the radiologist to optimize participation in multidisciplinary orthopedic oncology tumor boards, allowing for contribution to management decisions with expertise beyond image interpretation.
View details for DOI 10.1007/s00256-020-03567-w
View details for PubMedID 32743671
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Association of adipose tissue and skeletal muscle metrics with overall survival and postoperative complications in soft tissue sarcoma patients: an opportunistic study using computed tomography.
Quantitative imaging in medicine and surgery
2020; 10 (8): 1580-1589
Abstract
To determine the relationship between adipose tissue and skeletal muscle measurements on computed tomography (CT) and overall survival and major postoperative complications in patients with soft-tissue sarcoma (STS).The retrospective study included 137 STS patients (75 men, 62 women; mean age, 53 years, SD 17.7; mean BMI, 28.5, SD 6.6) who had abdominal CT exams. On a single CT image, at the L4 pedicle level, measurements of visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and skeletal muscle area and attenuation were obtained using clinical PACS and specialized segmentation software. Clinical information was recorded, including STS characteristics (size, depth, grade, stage, and site), overall survival, and postoperative complications. The relationships between CT metrics and survival were analyzed using Cox proportional hazard models and those between CT metrics and postoperative complications using logistic regression models.There were 33 deaths and 41 major postoperative complications. Measured on clinical PACS, the psoas area (P=0.003), psoas index (P=0.006), psoas attenuation (P=0.011), and total muscle attenuation (P=0.023) were associated with overall survival. Using specialized software, psoas attenuation was also associated with overall survival (P=0.018). Adipose tissue metrics were not associated with survival or postoperative complications.In STS patients, CT-derived muscle size and attenuation are associated with overall survival. These prognostic biomarkers can be obtained using specialized segmentation software or routine clinical PACS.
View details for DOI 10.21037/qims.2020.02.09
View details for PubMedID 32742953
View details for PubMedCentralID PMC7378098
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Value-Added Opportunistic CT: Insights Into Osteoporosis and Sarcopenia.
AJR. American journal of roentgenology
2020: 1–13
Abstract
OBJECTIVE. The purpose of this article is to review the emerging field of opportunistic CT, which can be used to screen patients for osteoporosis and sarcopenia. CONCLUSION. Although body composition measurements are not routinely obtained using CT, quantitative assessment of bone and muscle biomarkers on CT can add value to patient care. Automated bone and muscle measurements promise to transform the everyday practice of radiology without resulting in additional cost or radiation exposure for patients.
View details for DOI 10.2214/AJR.20.22874
View details for PubMedID 32755187
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Marrow uptake on FDG PET/CT is associated with progression from smoldering to symptomatic multiple myeloma.
Skeletal radiology
2020
Abstract
OBJECTIVE: To determine association of body composition measurements on CT and PET with progression of smoldering myeloma to multiple myeloma.METHODS: A retrospective cohort study in 65 patients with smoldering myeloma and PET/CT at diagnosis was performed at a tertiary cancer center. Subjects were between 38 and 87years of age (mean 64) and included 37 males. Primary outcome was progression-free survival as a function of bone, fat, and muscle metrics on CT and PET (measured at the level of L4 pedicles) and clinical confounders. CT metrics included attenuation of L4 and retroperitoneal fat and various indices derived from the psoas muscle. PET measures included SUVmax and SUVmean of L4, retroperitoneal fat, and psoas. Cox proportional hazards modeling was performed with entry and retention criteria of p<0.1 and p<0.05, respectively.RESULTS: SUVmax and SUVmean were associated for each compartment (R2=0.78-0.84), and SUVmean (SUV) was used for subsequent analyses. SUV of the L4 vertebral body was associated with attenuation of the L4 vertebral body (p=0.0032). There was no association between SUV and CT for muscle and fat compartments. In the subset of patients with bone marrow biopsy results (n=43), there was no association between SUV of L4 and plasma cell concentration on core biopsy or flow cytometry (p=0.089 and 0.072, respectively). The final Cox model showed association with albumin (HR 0.29, 95%CI 0.088-0.93, p=0.038), M protein (HR 1.31, 95%CI 1.021-1.68, p=0.034), and SUV of L4 (HR 1.99, 95%CI 1.037-3.82, p=0.039).CONCLUSION: SUV of L4 is a prognostic indicator in patients with smoldering myeloma.
View details for DOI 10.1007/s00256-020-03529-2
View details for PubMedID 32621061
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Capsular thinning on magnetic resonance arthrography is associated with intra-operative hip joint laxity in women.
Journal of hip preservation surgery
2020; 7 (2): 298–304
Abstract
Hip microinstability is a recognized cause of hip pain in young patients. Intra-operative evaluation is used to confirm the diagnosis, but limited data exist associating magnetic resonance arthrography (MRA) findings with hip microinstability. To determine if a difference exists in the thickness of the anterior joint capsule and/or the width of the anterior joint recess on MRA in hip arthroscopy patients with and without an intra-operative diagnosis of hip laxity. Sixty-two hip arthroscopy patients were included in the study. Two musculoskeletal radiologists blinded to surgical results reviewed the MRAs for two previously described findings: (i) anterior joint capsule thinning; (ii) widening of the anterior joint recess distal to the zona orbicularis. Operative reports were reviewed for the diagnosis of joint laxity. In all patients with and without intra-operative laxity, there were no significant differences with either MRA measurement. However, twenty-six of 27 patients with intra-operative laxity were women compared with 11 of 35 patients without laxity (P<0.001). In subgroup analysis of women, the intra-operative laxity group had a higher rate of capsular thinning compared with the non-laxity group (85% versus 45%; P=0.01). A 82% of women with capsular thinning also had intra-operative laxity, compared with 40% without capsular thinning (P=0.01). There were no differences regarding the width of the anterior joint recess. In this study, there was an association between capsular thinning and intra-operative laxity in female patients. Measuring anterior capsule thickness on a pre-operative MRA may be useful for the diagnosis of hip microinstability.
View details for DOI 10.1093/jhps/hnaa018
View details for PubMedID 33163215
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Accurate prediction of lumbar microdecompression level with an automated MRI grading system.
Skeletal radiology
2020
Abstract
OBJECTIVE: Lumbar spine MRI interpretations have high variability reducing utility for surgical planning. This study evaluated a convolutional neural network (CNN) framework that generates automated MRI grading for its ability to predict the level that was surgically decompressed.MATERIALS AND METHODS: Patients who had single-level decompression were retrospectively evaluated. Sagittal T2 images were processed by a CNN (SpineNet), which provided grading for the following: central canal stenosis, disc narrowing, disc degeneration, spondylolisthesis, upper/lower endplate morphologic changes, and upper/lower marrow changes. The grades were used to calculate an aggregate score. The variables and the aggregate score were analyzed for their ability to predict the surgical level. For each surgical level subgroup, the surgical level aggregate scores were compared with the non-surgical levels.RESULTS: A total of 141 patients met the inclusion criteria (82 women, 59 men; mean age 64years; age range 28-89years). SpineNet did not identify central canal stenosis in 32 patients. Of the remaining 109, 96 (88%) patients had a decompression at the level of greatest stenosis. The higher stenotic grade was present only at the surgical level in 82/96 (85%) patients. The level with the highest aggregate score matched the surgical level in 103/141 (73%) patients and was unique to the surgical level in 91/103 (88%) patients. Overall, the highest aggregate score identified the surgical level in 91/141 (65%) patients. The aggregate MRI score mean was significantly higher for the L3-S1 surgical levels.CONCLUSION: A previously developed CNN framework accurately predicts the level of microdecompression for degenerative spinal stenosis in most patients.
View details for DOI 10.1007/s00256-020-03505-w
View details for PubMedID 32607805
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Opportunistic muscle measurements on staging chest CT for extremity and truncal soft tissue sarcoma are associated with survival.
Journal of surgical oncology
2020
Abstract
BACKGROUND AND OBJECTIVES: Computed tomography (CT) measurements of sarcopenia have been proposed as biomarkers associated with outcomes in various cancers and have typically been evaluated at the L3 vertebral level. However, staging imaging for patients with extremity and truncal soft tissue sarcoma (STS) often only includes chest CT imaging which precludes evaluation at L3. Therefore, we sought to evaluate muscle metrics at T12 on standard staging chest CT scans and evaluate for correlation with overall and event-free survival in patients with STS.METHODS: CT chest imaging for 89 patients with intermediate and high-grade STS (53 male, 36 female; 58.5±19.0 years old, follow-up 37.4±27.1 months) was reviewed on PACS at T12 for skeletal muscle density (SMD) and skeletal muscle index (SMI).RESULTS: Overall survival increased with increased SMD on univariate (hazard ratio [HR]=0.61 [0.43, 0.86]) and age-adjusted analysis (HR=0.65 [0.42, 0.89]. Event-free survival also increased with increased SMD in univariate analyses (HR=0.68 [0.49, 0.95]) but did not maintain significance after adjusting for age (HR=0.68 [0.43, 1.07]). SMI was not a predictor of overall or event-free survival.CONCLUSIONS: Higher SMD measured on routinely obtained staging chest CTs in STS patients is associated with improved survival.
View details for DOI 10.1002/jso.26077
View details for PubMedID 32613648
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Automated Muscle Measurement on Chest Computed Tomography (CT) Predicts All-cause Mortality in Older Adults from the National Lung Screening Trial.
The journals of gerontology. Series A, Biological sciences and medical sciences
2020
Abstract
BACKGROUND: Muscle metrics derived from CT are associated with adverse health events in older persons, but obtaining these metrics using current methods is not practical for large datasets. We developed a fully-automated method for muscle measurement on CT images. This study aimed to determine the relationship between muscle measurements on CT with survival in a large multicenter trial of older adults.METHODS: The relationship between baseline paraspinous skeletal muscle area (SMA) and skeletal muscle density (SMD) and survival over 6 years was determined in 6803 men and 4558 women (baseline age: 60-69 years) in the National Lung Screening Trial (NLST). The automated machine learning pipeline selected appropriate CT series, chose a single image at T12, and segmented left paraspinous muscle, recording cross-sectional area and density. Associations between SMA and SMD with all-cause mortality were determined using sex-stratified Cox proportional hazards models, adjusted for age, race, height, weight, pack-years of smoking, and presence of diabetes, chronic lung disease, cardiovascular disease, and cancer at enrollment.RESULTS: After a mean 6.44 ± 1.06 years of follow-up, 635 (9.33%) men and 265 (5.81%) women died. In men, higher SMA and SMD were associated with a lower risk of all-cause mortality, in fully adjusted models. A one-unit standard deviation increase was associated with a hazard ratio (HR)=0.85 (95%CI=0.79,0.91;p<0.001) for SMA and HR=0.91 (95%CI=0.84,0.98;p=0.012) for SMD. In women, the associations did not reach significance.CONCLUSION: Higher paraspinous SMA and SMD, automatically derived from CT exams, were associated with better survival in a large multicenter cohort of community-dwelling older men.
View details for DOI 10.1093/gerona/glaa141
View details for PubMedID 32504466
- Top 3 Differentials in Musculoskeletal Imaging: A Case Review. Thieme. 2020
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Preoperative MRI of Articular Cartilage in the Knee: A Practical Approach.
The journal of knee surgery
2020; 33 (11): 1088–99
Abstract
Articular cartilage of the knee can be evaluated with high accuracy by magnetic resonance imaging (MRI) in preoperative patients with knee pain, but image quality and reporting are variable. This article discusses the normal MRI appearance of articular cartilage as well as the common MRI abnormalities of knee cartilage that may be considered for operative treatment. This article focuses on a practical approach to preoperative MRI of knee articular cartilage using routine MRI techniques. Current and future directions of knee MRI related to articular cartilage are also discussed.
View details for DOI 10.1055/s-0040-1716719
View details for PubMedID 33124010
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CT Phantom Evaluation of 67,392 ACR Accreditation Examinations: Implications for Opportunistic Screening of Osteoporosis Using CT.
AJR. American journal of roentgenology
2020
Abstract
Please see the Author Video associated with this article. OBJECTIVE. To investigate if there is a systematic bias in CT number (Hounsfield unit) measurements between scanners made by four major CT manufacturers. METHODS. CT number accuracy data acquired using the American College of Radiology (ACR) accreditation phantom were evaluated in a blinded fashion for four CT manufacturers (A: n=8,500; B: n=18,575; C: n=8,278, D: n=32,039). The CT number of water, acrylic (surrogate for trabecular bone), and teflon (surrogate for cortical bone) for an adult abdomen CT technique (120 kV, 240 mA, 50-cm FOV, standard reconstruction algorithm) was used in the analysis. Differences in HU values across all manufacturers were assessed using the Kruskal-Wallis test followed by a post-hoc test for pairwise comparisons. RESULTS. The mean CT number of water ranged from -0.3 to 2.7 HU, with highly significant differences between all manufacturers (p < 0.001). For the trabecular bone surrogate, differences in CT numbers across all manufacturers were also highly significant (p < 0.001), with mean values [standard deviation, SD] of 120.9 [3.5], 124.6 [3.3], 126.9 [4.4], and 123.9 [3.4] for manufacturers A, B, C, and D, respectively. For the cortical bone surrogate, differences in CT numbers across all manufacturers were also highly significant (p < 0.001), with mean values [SD] of 939.0 [14.2], 874.3 [13.3], 897.6 [11.3], and 912.7 [13.4] for manufacturers A, B, C, and D, respectively. CONCLUSION. CT number measurements between manufacturers have a systematic offset when compared to each other. Knowledge of these offsets is useful for optimizing the accuracy of opportunistic diagnosis of osteoporosis.
View details for DOI 10.2214/AJR.20.22943
View details for PubMedID 32755177
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Opportunistic body composition evaluation in patients with esophageal adenocarcinoma: association of survival with 18F-FDG PET/CT muscle metrics.
Annals of nuclear medicine
2019
Abstract
OBJECTIVE: 18F-FDG PET is widely used to accurately stage numerous types of cancers. Although 18F-FDG PET/CT features of tumors aid in predicting patient prognosis, there is increasing interest in mining additional quantitative body composition data that could improve the prognostic power of 18F-FDG PET/CT, without additional examination costs or radiation exposure. The aim of this study was to determine the association between overall survival and body composition metrics derived from routine clinical 18F-FDG PET/CT examinations.METHODS: Patients who received baseline 18F-FDG PET/CT imaging during workup for newly diagnosed esophageal adenocarcinoma (EAC) were included. From these studies, psoas cross-sectional area (CSA), muscle attenuation (MA), SUVmean, and SUVmax were obtained. Correlation with overall survival was assessed using a Cox Proportional Hazards model, controlling for age, body mass index, 18F-FDG dose, glucose level, diabetes status, in-hospital status, and tumor stage.RESULTS: Among the 59 patients studied, psoas MA and SUVmax were found to be significant predictors of survival (HR 0.94, 95% CI 0.88-0.99, p=0.04, and HR 0.37, 95% CI 0.14-0.97, p=0.04, respectively) and remained independent predictors. Psoas CSA and SUVmean did not significantly influence survival outcomes.CONCLUSIONS: Characterization of psoas muscles as a surrogate marker for sarcopenia on baseline 18F-FDG PET/CT imaging is relatively easily obtained and may offer additional prognostic value in patients with EAC.
View details for DOI 10.1007/s12149-019-01429-7
View details for PubMedID 31823231
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Automated Segmentation of Tissues Using CT and MRI: A Systematic Review.
Academic radiology
2019; 26 (12): 1695-1706
Abstract
The automated segmentation of organs and tissues throughout the body using computed tomography and magnetic resonance imaging has been rapidly increasing. Research into many medical conditions has benefited greatly from these approaches by allowing the development of more rapid and reproducible quantitative imaging markers. These markers have been used to help diagnose disease, determine prognosis, select patients for therapy, and follow responses to therapy. Because some of these tools are now transitioning from research environments to clinical practice, it is important for radiologists to become familiar with various methods used for automated segmentation.The Radiology Research Alliance of the Association of University Radiologists convened an Automated Segmentation Task Force to conduct a systematic review of the peer-reviewed literature on this topic.The systematic review presented here includes 408 studies and discusses various approaches to automated segmentation using computed tomography and magnetic resonance imaging for neurologic, thoracic, abdominal, musculoskeletal, and breast imaging applications.These insights should help prepare radiologists to better evaluate automated segmentation tools and apply them not only to research, but eventually to clinical practice.
View details for DOI 10.1016/j.acra.2019.07.006
View details for PubMedID 31405724
View details for PubMedCentralID PMC6878163
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Machine Learning for Automatic Paraspinous Muscle Area and Attenuation Measures on Low-Dose Chest CT Scans.
Academic radiology
2019; 26 (12): 1686-1694
Abstract
To develop and evaluate an automated machine learning (ML) algorithm for segmenting the paraspinous muscles on chest computed tomography (CT) scans to evaluate for presence of sarcopenia.A convolutional neural network based on the U-Net architecture was trained to perform muscle segmentation on a dataset of 1875 single slice CT images and was tested on 209 CT images of participants in the National Lung Screening Trial. Low-dose, noncontrast CT examinations were obtained at 33 clinical sites, using scanners from four manufacturers. The study participants had a mean age of 71.6 years (range, 70-74 years). Ground truth was obtained by manually segmenting the left paraspinous muscle at the level of the T12 vertebra. Muscle cross-sectional area (CSA) and muscle attenuation (MA) were recorded. Comparison between the ML algorithm and ground truth measures of muscle CSA and MA were obtained using Dice similarity coefficients and Pearson correlations.Compared to ground truth segmentation, the ML algorithm achieved median (standard deviation) Dice scores of 0.94 (0.04) in the test set. Mean (SD) muscle CSA was 14.3 (3.6) cm2 for ground truth and 13.7 (3.5) cm2 for ML segmentation. Mean (SD) MA was 41.6 (7.6) Hounsfield units (HU) for ground truth and 43.5 (7.9) HU for ML segmentation. There was high correlation between ML algorithm and ground truth for muscle CSA (r2 = 0.86; p < 0.0001) and MA (r2 = 0.95; p < 0.0001).The ML algorithm for measurement of paraspinous muscles compared favorably to manual ground truth measurements in the NLST. The algorithm generalized well to a heterogeneous set of low-dose CT images and may be capable of automated quantification of muscle metrics to screen for sarcopenia on routine chest CT examinations.
View details for DOI 10.1016/j.acra.2019.06.017
View details for PubMedID 31326311
View details for PubMedCentralID PMC6878160
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The medial epicondyle of the distal femur is the optimal location for MRI measurement of semitendinosus and gracilis tendon cross-sectional area.
Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA
2019; 27 (11): 3498-3504
Abstract
Graft diameter ≥ 8 mm reduces the risk of failure after anterior cruciate ligament reconstruction (ALCR) with hamstring tendon autograft. Pre-operative measurement of gracilis (GT) and semitendinosus (ST) cross-sectional area using MRI has been utilized but the optimal location for measurement is unknown. The main purpose of this study was to examine the cross-sectional areas of GT + ST at different locations and develop a model to predict whether a doubled hamstring graft of GT + ST will be of sufficient cross-sectional area for ACLR.A retrospective review was performed of 154 patients who underwent primary ACLR using doubled hamstring autograft. Cross-sectional area measurements of GT + ST on pre-operative MRI axial images were made at three locations: medial epicondyle (ME), tibiofemoral joint line (TJL), and tibial physeal scar (TPS) and calculated the correlation of intra-operative graft size for each location using the Pearson's correlation coefficient. A receiver operating characteristic (ROC) established a threshold that would predict graft diameter ≥ 8 mm.Measurement of GT + ST at the ME had a stronger correlation (r = 0.389) to intra-operative graft diameter than measurements at the TJL (r = 0.256) or TPS (r = 0.240). The ROC indicated good predictive value for hamstring graft diameter ≥ 8 mm based on MRI measurement at the ME with the optimal threshold with the highest sensitivity and specificity as 18 mm2.Cross-sectional area measurement of GT + ST at the ME correlated most closely to intra-operative diameter of a doubled hamstring autograft compared to measurements at the TJL or the TPS. As graft diameter < 8 mm is correlated with higher failure rates of ACL surgery, the ability to pre-operatively predict graft diameter is clinically useful.Level III, prognostic study.
View details for DOI 10.1007/s00167-019-05421-6
View details for PubMedID 30809723
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Real-time three-dimensional MRI for the assessment of dynamic carpal instability.
PloS one
2019; 14 (9): e0222704
Abstract
Carpal instability is defined as a condition where wrist motion and/or loading creates mechanical dysfunction, resulting in weakness, pain and decreased function. When conventional methods do not identify the instability patterns, yet clinical signs of instability exist, the diagnosis of dynamic instability is often suggested to describe carpal derangement manifested only during the wrist's active motion or stress. We addressed the question: can advanced MRI techniques provide quantitative means to evaluate dynamic carpal instability and supplement standard static MRI acquisition? Our objectives were to (i) develop a real-time, three-dimensional MRI method to image the carpal joints during their active, uninterrupted motion; and (ii) demonstrate feasibility of the method for assessing metrics relevant to dynamic carpal instability, thus overcoming limitations of standard MRI.Twenty wrists (bilateral wrists of ten healthy participants) were scanned during radial-ulnar deviation and clenched-fist maneuvers. Images resulting from two real-time MRI pulse sequences, four sparse data-acquisition schemes, and three constrained image reconstruction techniques were compared. Image quality was assessed via blinded scoring by three radiologists and quantitative imaging metrics.Real-time MRI data-acquisition employing sparse radial sampling with a gradient-recalled-echo acquisition and constrained iterative reconstruction appeared to provide a practical tradeoff between imaging speed (temporal resolution up to 135 ms per slice) and image quality. The method effectively reduced streaking artifacts arising from data undersampling and enabled the derivation of quantitative measures pertinent to evaluating dynamic carpal instability.This study demonstrates that real-time, three-dimensional MRI of the moving wrist is feasible and may be useful for the evaluation of dynamic carpal instability.
View details for DOI 10.1371/journal.pone.0222704
View details for PubMedID 31536561
View details for PubMedCentralID PMC6752861
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Subchondroplasty of the Ankle and Hindfoot for Treatment of Osteochondral Lesions and Stress Fractures: Initial Imaging Experience.
Foot & ankle specialist
2019: 1938640019863252
Abstract
Objective:To describe the imaging findings of patients treated with subchondroplasty (SCP) of the ankle and hindfoot. Materials and Methods: Eighteen patients (10 men, 8 women; age mean 43.1 years [range 20.1-67.7 years]) underwent ankle and hindfoot SCP at a single center over a 14-month period. Imaging data were reviewed retrospectively by 2 radiologists by consensus interpretation, including preoperative radiography (18), computed tomography (CT) (11), and magnetic resonance imaging (MRI) (13) and postoperative radiography (10), CT (4), and MRI (6). Follow-up imaging was acquired 1 month to 1.6 years following SCP. Results: Indications for SCP included symptomatic bone marrow lesions (BMLs) secondary to an osteochondral lesion (OCL) (16/18) or stress fracture (2/18). While focal radiodensity related to the SCP procedure was retrospectively identifiable on postoperative radiography in all except 1 case (10/11), postprocedural findings were not described by the interpreting radiologist in 6/11 cases. On CT, the average injected synthetic calcium phosphate (CaP) volume was 1.15 cm3 (SD = 0.33 cm3); mean CT attenuation of the injectate was 1220 HU (range 1058-1465 HU). In all patients who had pre- and postoperative MRI (5/18), BML size decreased on follow-up MRI. Extra-osseous extrusion of CaP was not seen on postoperative radiography, CT, or MRI. Conclusion: Physicians should be aware of the expanding preoperative indications and postoperative imaging findings of SCP, which is being performed with increasing frequency in the ankle and hindfoot. Levels of Evidence: Diagnostic, Level III: Retrospective cohort study.
View details for DOI 10.1177/1938640019863252
View details for PubMedID 31315447
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Dynamic MRI of the wrist in less than 20 seconds: normal midcarpal motion and reader reliability.
Skeletal radiology
2019
Abstract
To describe the normal motion pattern at the midcarpal compartment during active radial-ulnar deviation of the wrist using dynamic MRI, and to determine the observer performance for measurements obtained in asymptomatic volunteers.Dynamic MRI of 35 wrists in 19 asymptomatic volunteers (age mean 30.4 years, SD 8.6) was performed during active radial-ulnar deviation using a fast gradient-echo pulse sequence with 315 ms temporal resolution (acquisition time, 19 s). Two independent readers measured the transverse translation of the trapezium at the scaphotrapezium joint (STJ) and the capitate-to-triquetrum distance (CTD). Relationships between these measurements and laterality, sex, lunate type, and wrist kinematic pattern were evaluated.At the STJ, the trapezium moved most in radial deviation, with an overall translation of 2.3 mm between ulnar and radial deviation. Mean CTD measurements were the greatest in ulnar deviation and varied 2.4 mm between ulnar and radial deviation. Mean CTD was greater in men than women in the neutral position (p = 0.019), and in wrists with type II lunate morphology during radial and ulnar deviation (p = 0.001, p = 0.014). There were no significant differences in trapezium translation or CTD with wrist laterality and kinematic pattern. Intraobserver and interobserver correlation coefficients were 0.97 and 0.87 for trapezium translation and 0.84 and 0.67 for CTD.This study is the first to demonstrate the performance of dynamic MRI to quantify STJ motion and CTD. Dynamic MRI with a short acquisition time may be used as a tool to supplement static MRI in evaluation of the midcarpal compartment.
View details for DOI 10.1007/s00256-019-03266-1
View details for PubMedID 31289900
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Opportunistic Measurement of Skeletal Muscle Size and Muscle Attenuation on Computed Tomography Predicts 1-Year Mortality in Medicare Patients.
The journals of gerontology. Series A, Biological sciences and medical sciences
2019; 74 (7): 1063-1069
Abstract
Opportunistic assessment of sarcopenia on CT examinations is becoming increasingly common. This study aimed to determine relationships between CT-measured skeletal muscle size and attenuation with 1-year risk of mortality in older adults enrolled in a Medicare Shared Savings Program (MSSP).Relationships between skeletal muscle metrics and all-cause mortality were determined in 436 participants (52% women, mean age 75 years) who had abdominopelvic CT examinations. On CT images, skeletal muscles were segmented at the level of L3 using two methods: (a) all muscles with a threshold of -29 to +150 Hounsfield units (HU), using a dedicated segmentation software, (b) left psoas muscle using a free-hand region of interest tool on a clinical workstation. Muscle cross-sectional area (CSA) and muscle attenuation were measured. Cox regression models were fit to determine the associations between muscle metrics and mortality, adjusting for age, sex, race, smoking status, cancer diagnosis, and Charlson comorbidity index.Within 1 year of follow-up, 20.6% (90/436) participants died. In the fully-adjusted model, higher muscle index and muscle attenuation were associated with lower risk of mortality. A one-unit standard deviation (SD) increase was associated with a HR = 0.69 (95% CI = 0.49, 0.96; p = .03) for total muscle index, HR = 0.67 (95% CI = 0.49, 0.90; p < .01) for psoas muscle index, HR = 0.54 (95% CI = 0.40, 0.74; p < .01) for total muscle attenuation, and HR = 0.79 (95% CI = 0.66, 0.95; p = .01) for psoas muscle attenuation.In older adults, higher skeletal muscle index and muscle attenuation on abdominopelvic CT examinations were associated with better survival, after adjusting for multiple risk factors.
View details for DOI 10.1093/gerona/gly183
View details for PubMedID 30124775
View details for PubMedCentralID PMC6765059
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Approaches to Assessment of Muscle Mass and Myosteatosis on Computed Tomography (CT): A Systematic Review.
The journals of gerontology. Series A, Biological sciences and medical sciences
2019
Abstract
There is increasing use of computed tomography (CT) in sarcopenia research using a wide variety of techniques. We performed a systematic review of the CT literature to identify the differences between approaches used. A comprehensive search of PubMed from 1983-2017 was performed to identify studies that used CT muscle measurements to assess muscle mass and myosteatosis. The CT protocols were evaluated based on: anatomic landmark(s), thresholding, muscle(s) segmented, key measurement (i.e., muscle attenuation, cross-sectional area, volume), derived variables, and analysis software. From the described search, 657 articles were identified and 388 studies met inclusion criteria for this systematic review. Muscle mass was more commonly assessed than myosteatosis (330 vs 125). The most commonly assessed muscle or muscle groups were total abdominal wall musculature (142/330 and 49/125 for muscle mass and myosteatosis, respectively) and total thigh musculature (90/330 and 48/125). The most commonly used landmark in the abdomen was the L3 vertebra (123/142 and 45/49 for muscle mass and myosteatosis, respectively). Skeletal muscle index (SMI) and inter-muscular adipose tissue (IMAT) were the most commonly used measures of abdominal wall muscle mass (114/142) and myosteatosis (27/49), respectively. Cut-points varied across studies. A significant majority of studies failed to report important CT technical parameters, such as use of intravenous contrast and slice thickness (94% and 63%, respectively). There is considerable variation in the CT approaches used for the assessment of muscle mass and myosteatosis. There is a need to develop consensus for CT-based evaluation of sarcopenia and myosteatosis.
View details for DOI 10.1093/gerona/glz034
View details for PubMedID 30726878
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Tears in the distal superficial medial collateral ligament: the wave sign and other associated MRI findings.
Skeletal radiology
2019
Abstract
To analyze the MRI characteristics of distal superficial medial collateral ligament (sMCL) tears and to identify features of tears displaced superficial to the pes anserinus (Stener-like lesion (SLL)).Knee MRI examinations at four institutions were selected which showed tears of the sMCL located distal to the joint line. MRIs were evaluated for a SLL, a wavy contour to the sMCL, and the location of the proximal sMCL stump. Additional coexistent knee injuries were recorded.The study included 51 patients (mean age, 28 years [sd, 12]). A SLL was identified in 20 of 51 cases. The proximal stump margin was located significantly (p < 0.01) more distal and more medial with a SLL (mean = 33 mm [sd = 11 mm] and mean = 6.5 mm [sd = 2.5 mm], respectively), than without a SLL (mean = 19 mm [sd = 16 mm] and mean = 4.8 mm [sd = 2.4 mm], respectively). Medial compartment osseous injury was significantly (p < 0.05) more common with a SLL (75%) than without a SLL (42%). The frequency of concomitant injuries in the group (ACL tear, 82%; PCL tear, 22%; deep MCL tear, 61%; lateral compartment osseous injury, 94%) did not differ significantly between patients with and without a SLL.A distal sMCL tear should be considered when MRI depicts a wavy appearance of the sMCL. Distal sMCL tears have a frequent association with concomitant knee injuries, especially ACL tears and lateral femorotibial osseous injuries. A SLL is particularly important to recognize because of implications for treatment.
View details for DOI 10.1007/s00256-019-03352-4
View details for PubMedID 31820044
- Imaging of the Musculoskeletal System Chapman’s Comprehensive Orthopaedic Surgery 2019; 4th
- Imaging of Bone Tumors Chapman’s Comprehensive Orthopaedic Surgery 2019
- Imaging of Soft-tissue Tumors Chapman’s Comprehensive Orthopaedic Surgery 2019
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Opportunistic Screening for Osteoporosis Using Computed Tomography: State of the Art and Argument for Paradigm Shift.
Current rheumatology reports
2018; 20 (12): 74
Abstract
Osteoporosis is disproportionately common in rheumatology patients. For the past three decades, the diagnosis of osteoporosis has benefited from well-established practice guidelines that emphasized the use of dual x-ray absorptiometry (DXA). Despite these guidelines and the wide availability of DXA, approximately two thirds of eligible patients do not undergo testing. One strategy to improve osteoporosis testing is to employ computed tomography (CT) examinations obtained as part of routine patient care to "opportunistically" screen for osteoporosis, without additional cost or radiation exposure to patients. This review examines the role of opportunistic CT in the evaluation of osteoporosis.Recent evidence suggests that opportunistic measurement of bone attenuation (radiodensity) using CT has sensitivity comparable to DXA. More importantly, such an approach has been shown to predict osteoporotic fractures. The paradigm shift of using CTs obtained for other reasons to opportunistically screen for osteoporosis promises to substantially improve patient care.
View details for DOI 10.1007/s11926-018-0784-7
View details for PubMedID 30317448
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MR Imaging of SLAP Lesions.
The open orthopaedics journal
2018; 12: 314-323
Abstract
SLAP lesions of the shoulder are challenging to diagnose by clinical means alone. Interpretation of MR images requires knowledge of the normal appearance of the labrum, its anatomical variants, and the characteristic patterns of SLAP lesions. In general, high signal extending anterior and posterior to the biceps anchor is the hallmark of SLAP lesions. Common diagnostic criteria for a SLAP lesion by MR or MR arthrography include the following: presence of a laterally curved, high signal intensity in the labrum on a coronal image, multiple or branching lines of high signal intensity in the superior labrum on a coronal image, full-thickness detachment with irregularly marginated high signal intensity and/or separation >2 mm on conventional MRI or 3 mm on MR arthrography between the labrum and glenoid on a coronal image, and a paralabral cyst extending from the superior labrum.MR diagnosis of SLAP tears may be improved with provocative maneuvers, such as longitudinal traction of the arm or positioning of the shoulder in abduction and external rotation during imaging. The use of intra-articular contrast distends the joint similar to what occurs during arthroscopy and forced diffusion under the labrum may improve the ability to detect SLAP lesions that might not be seen with standard MR. Improved diagnostic accuracy for SLAP tears is seen with 3-T compared with 1.5-T MR imaging, with or without intra-articular contrast material.Regardless of MR findings, however, physicians should be cautious when recommending surgery in the patient with a vague clinical picture. The patient's history, physical exam, and imaging evaluation all should be considered together in making the decision to proceed with surgery.
View details for DOI 10.2174/1874325001812010314
View details for PubMedID 30197713
View details for PubMedCentralID PMC6110058
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Sarcopenia: Beyond Muscle Atrophy and into the New Frontiers of Opportunistic Imaging, Precision Medicine, and Machine Learning.
Seminars in musculoskeletal radiology
2018; 22 (3): 307-322
Abstract
As populations continue to age worldwide, the impact of sarcopenia on public health will continue to grow. The clinically relevant and increasingly common diagnosis of sarcopenia is at the confluence of three tectonic shifts in medicine: opportunistic imaging, precision medicine, and machine learning. This review focuses on the state-of-the-art imaging of sarcopenia and provides context for such imaging by discussing the epidemiology, pathophysiology, consequences, and future directions in the field of sarcopenia.
View details for DOI 10.1055/s-0038-1641573
View details for PubMedID 29791959
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Skeletal Muscle Metrics on Clinical 18F-FDG PET/CT Predict Health Outcomes in Patients with Sarcoma.
Journal of nature and science
2018; 4 (5)
Abstract
The aim of this study was to determine the association of measures of skeletal muscle determined from 18F-FDG PET/CT with health outcomes in patients with soft-tissue sarcoma. 14 patients (8 women and 6 men; mean age 66.5 years) with sarcoma had PET/CT examinations. On CTs of the abdomen and pelvis, skeletal muscle was segmented, and cross-sectional muscle area, muscle volume, and muscle attenuation were determined. Within the segmented muscle, intramuscular fat area, volume, and density were derived. On PET images, the standardized uptake value (SUV) of muscle was determined. Regression analyses were conducted to determine the association between the imaging measures and health outcomes including overall survival (OS), local recurrence-free survival (LRFS), distant cancer recurrence (DCR), and major surgical complications (MSC). The association between imaging metrics and pre-therapy levels of serum C-reactive protein (CRP), creatinine, hemoglobin, and albumin was determined. Decreased volumetric muscle CT attenuation was associated with increased DCR. Increased PET SUV of muscle was associated with decreased OS and LRFS. Lower muscle SUV was associated with lower serum hemoglobin and albumin. Muscle measurements obtained on routine 18F-FDG PET/CT are associated with outcomes and serum hemoglobin and albumin in patients with sarcoma.
View details for PubMedID 29756042
View details for PubMedCentralID PMC5944355
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WRIST: A WRist Image Segmentation Toolkit for carpal bone delineation from MRI.
Computerized medical imaging and graphics : the official journal of the Computerized Medical Imaging Society
2018; 63: 31-40
Abstract
Segmentation of the carpal bones from 3D imaging modalities, such as magnetic resonance imaging (MRI), is commonly performed for in vivo analysis of wrist morphology, kinematics, and biomechanics. This crucial task is typically carried out manually and is labor intensive, time consuming, subject to high inter- and intra-observer variability, and may result in topologically incorrect surfaces. We present a method, WRist Image Segmentation Toolkit (WRIST), for 3D semi-automated, rapid segmentation of the carpal bones of the wrist from MRI. In our method, the boundary of the bones were iteratively found using prior known anatomical constraints and a shape-detection level set. The parameters of the method were optimized using a training dataset of 48 manually segmented carpal bones and evaluated on 112 carpal bones which included both healthy participants without known wrist conditions and participants with thumb basilar osteoarthritis (OA). Manual segmentation by two expert human observers was considered as a reference. On the healthy subject dataset we obtained a Dice overlap of 93.0 ± 3.8, Jaccard Index of 87.3 ± 6.2, and a Hausdorff distance of 2.7 ± 3.4 mm, while on the OA dataset we obtained a Dice overlap of 90.7 ± 8.6, Jaccard Index of 83.0 ± 10.6, and a Hausdorff distance of 4.0 ± 4.4 mm. The short computational time of 20.8 s per bone (or 5.1 s per bone in the parallelized version) and the high agreement with the expert observers gives WRIST the potential to be utilized in musculoskeletal research.
View details for DOI 10.1016/j.compmedimag.2017.12.003
View details for PubMedID 29331208
View details for PubMedCentralID PMC5803471
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Association of lunate morphology, sex, and lunotriquetral interosseous ligament injury with radiologic measurement of the capitate-triquetrum joint.
Skeletal radiology
2017; 46 (12): 1729-1737
Abstract
Radiologic presentation of carpal instability at the radial side of the carpus, e.g. scapholunate diastasis following scapholunate interosseous ligament injury, has been studied extensively. By comparison, presentation at the ulnar-sided carpus has not. The purpose of this study was to assess the effects of lunate morphology, sex, and lunotriquetral interosseous ligament (LTIL) status on the radiologic measurement of the capitate-triquetrum joint (C-T distance). Further, we sought to evaluate the diagnostic accuracy of C-T distance for assessing LTIL injuries.We retrospectively identified 223 wrists with wrist radiographs and MR arthrograms with contrast injection. Data collected included sex, lunate morphology and LTIL status from MR arthrography, and C-T distance from radiography. The effects of lunate morphology, sex, and LTIL injury status on C-T distance were evaluated using generalized linear models. Diagnostic performance of C-T distance was assessed by the area under receiver-operator characteristic curve (AUROC).Lunate morphology, sex, and LTIL injury status all had significant effects on C-T distance; wrists with type II lunates, men, and wrists with LTIL injuries had greater C-T distances than wrists with type I lunates, women, and wrists without LTIL injuries, respectively (p < 0.01). The diagnostic value of the C-T distance for identifying patients with full-thickness LTIL tears was sufficient for women with type I (AUROC = 0.67) and type II lunates (0.60) and good for men with type I (0.72) and type II lunates (0.77). The demonstrated influence of LTIL status on C-T distance supports the use of C-T distance as a tool in assessing for full-thickness LTIL tears.
View details for DOI 10.1007/s00256-017-2747-x
View details for PubMedID 28828602
View details for PubMedCentralID PMC5710747
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Musculotendinous Disorders in the Upper Extremity: Part 2. MRI of the Elbow, Forearm, Wrist, and Hand.
Seminars in musculoskeletal radiology
2017; 21 (4): 376-391
View details for DOI 10.1055/s-0037-1604008
View details for PubMedID 28772316
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Muscle Imaging: Beyond the Basics.
Seminars in musculoskeletal radiology
2017; 21 (4): 357-358
View details for DOI 10.1055/s-0037-1604182
View details for PubMedID 28772314
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Musculotendinous Disorders in the Upper Extremity: Part 1. MRI of the Shoulder and Upper Arm.
Seminars in musculoskeletal radiology
2017; 21 (4): 359-375
View details for DOI 10.1055/s-0037-1604009
View details for PubMedID 28772315
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CT of Patients With Hip Fracture: Muscle Size and Attenuation Help Predict Mortality.
AJR. American journal of roentgenology
2017; 208 (6): W208-W215
Abstract
Our objective was to determine the association between muscle cross-sectional area and attenuation, as measured on routine CT scans, and mortality in older patients with hip fracture.A retrospective 10-year study of patients with hip fracture was conducted with the following inclusion criteria: age 65 years or older, first-time hip fracture treated with surgery, and CT of the chest, abdomen, or pelvis. This yielded 274 patients (70.4% women; mean [± SD] age, 81.3 ± 8.3 years). On each CT scan, two readers independently measured the size (cross-sectional area, indexed for patient height) and attenuation of the paravertebral muscle at T12 and the psoas muscle at L4. We then determined the association between overall mortality and the muscle size and muscle attenuation, while adjusting for demographic variables (age, sex, ethnicity, and body mass index), American Society of Anesthesiologists (ASA) classification, and Charlson comorbidity index (CCI).The overall mortality rate increased from 28.3% at 1 year to 79.5% at 5 years. Mortality was associated with decreased thoracic muscle size (odds ratio [OR], 0.66; 95% CI, 0.49-0.87). This association persisted after adjusting for demographic variables (OR, 0.69; 95% CI, 0.50-0.95), the ASA classification (OR, 0.70; CI, 0.51-0.97), and the CCI (OR, 0.72; 95% CI, 0.52-1.00). Similarly, decreased survival was associated with decreased thoracic muscle attenuation after adjusting for all of these combinations of covariates (OR, 0.67-0.72; 95% CI, 0.49-0.99). Decreased lumbar muscle size and attenuation trended with decreased survival but did not reach statistical significance.In older adults with hip fractures, CT findings of decreased thoracic paravertebral muscle size and attenuation are associated with decreased overall survival.
View details for DOI 10.2214/AJR.16.17226
View details for PubMedID 28267356
View details for PubMedCentralID PMC5898447
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Pelvic Tilt Evaluation From Frontal Radiographs: The Validity, Interobserver Reliability and Intraobserver Reproducibility of the Sacro-Femoral-Pubic Parameter.
The Journal of arthroplasty
2017; 32 (5): 1665-1669
Abstract
The sacro-femoral-pubic (SFP) parameter, calculated using the SFP angle measured on a frontal pelvis radiograph, has previously been shown to have a strong correlation with sagittal pelvic tilt (PT) measured on a lateral x-ray. The purpose of this study is to assess the validity, interobserver reliability and intraobserver reproducibility of the SFP parameter in predicting the sagittal PT.This is a retrospective study of 100 patients with frontal and lateral radiographs of the pelvis. Two observers independently measured the SFP angle on frontal x-ray (midpoint of S1 end plate to centroid of acetabula to upper midpoint of the pubic symphysis) and PT on lateral x-ray (midpoint of sacral plate to the centroid of acetabula to vertical plane). The SFP parameter was defined using the equation: SFP parameter = 75 - SFP angle. The interobserver reliability and intraobserver reproducibility were calculated using interclass correlation coefficient (ICC). Validity of the SFP parameter was calculated using Pearson correlation coefficient.The intraobserver reproducibility of the SFP parameter was excellent (ICC >0.90) for both observers. The interobserver reliability of all measurements was substantial for the SFP parameter (ICC >0.80) and PT (ICC >0.70). The concurrent validity of the SFP parameter was substantial (r = 0.70).Calculating PT from a frontal radiograph using the equation for the SFP parameter is a valid, reliable, and reproducible formula that may be used to predict sagittal PT.
View details for DOI 10.1016/j.arth.2016.11.026
View details for PubMedID 28012720
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"Knuckle Cracking": Can Blinded Observers Detect Changes with Physical Examination and Sonography?
Clinical orthopaedics and related research
2017; 475 (4): 1265-1271
Abstract
Voluntary knuckle cracking is a common habit, with a reported prevalence of 25% to 45%. Habitual knuckle cracking also is a frequent source of questions for physicians, and the largest study to date reported an association with functional hand impairments.(1) When compared with subjects who are not habitual knuckle crackers, do habitual knuckle crackers have greater QuickDASH scores, swelling, weakness, joint laxity, or ROM? (2) In subjects who crack their knuckles, does cracking immediately increase ROM? (3) What are the characteristic sonographic findings in joints that crack?A prospective, institutional review board-approved study was performed on 400 metacarpophalangeal joints (MPJs) in 40 asymptomatic adult subjects. Of those, 30 subjects had a history of habitual knuckle cracking (defined as daily voluntary popping of MPJs). Clinical history provided by all subjects included a standardized QuickDASH questionnaire. Physical examination was performed by two orthopaedic surgeons (blinded to subjects' knuckle-cracking history and sonographic outcomes). The physical examination included evaluation for swelling, grip strength, and ROM before and after attempted knuckle cracking. Sonographic examination was conducted by one sonographer, with static and real-time cine images recorded before, during, and after MPJ distraction was performed by the subjects. Two musculoskeletal radiologists (blinded to subjects' knuckle-cracking history) interpreted the images for a definite hyperechoic focus during and after MPJ distraction; this was compared against the reference standard of an audible "crack" during joint distraction.Comparing subjects with knuckle cracking with those who did not crack their knuckles, there was no differences in QuickDASH scores (knuckle crackers, 3.7 ± 5.2; nonknuckle crackers, 3.2 ± 6.3; mean difference, 0.6; 95% CI, -3.5 to 4.6; p = 0.786), laxity (knuckle crackers, 2.0 ± 1.8; nonknuckle crackers, 0.3 ± 0.7; mean difference, 1.7; 95% CI, 0.5-2.9; p = 0.191), and grip strength (preultrasound, right hand, p = 0.499, left hand p = 0.575; postultrasound, right hand p = 0.777, left hand p = 0.424); ROM comparisons between subjects with a history of habitual knuckle cracking versus subjects without such a history only yielded increased ROM in joints that cracked during manipulation (knuckle cracking, 143.8° ± 26.5°; nonknuckle cracking, 134.9° ± 28.6°; mean difference, 9.0°; 95% CI, 2.9°-15.1°; p = 0.004). Swelling was not observed in any subjects, including when comparing MPJs before versus after distraction maneuvers that resulted in audible cracks. Immediately after a documented crack, there were greater ranges of motion with active flexion (preultrasound, 85.7° ± 12.4°; postultrasound, 88.6° ± 11.6°; mean difference, -2.9°; 95% CI, -5.1° to -0.8°; p = 0.009), passive flexion (preultrasound, 96.1° ± 12.4°; postultrasound, 100.3° ± 10.4°; mean difference, -4.3°; 95% CI, -6.2° to -2.3°; p < 0.001), passive extension (preultrasound, 41.8° ± 18.1°; postultrasound, 45.2° ± 17.6°; mean difference, -3.5°; 95% CI, -6.9° to -0.1°; p = 0.046), and passive total ROM (preultrasound, 137.8° ± 24.8°; postultrasound, 145.6° ± 23.1°; mean difference, -7.7°; 95% CI, -11.7° to -3.8°; p < 0.001). The characteristic sonographic finding observed during cracking events is an echogenic focus that appears de novo dynamically in the joint during distraction.We found no evidence of immediate adverse physical examination findings after knuckle cracking. However, we did find a small increase in ROM among joints that cracked compared with those that did not. Future studies should examine if there are any long-term beneficial and adverse clinical outcomes associated with habitual knuckle cracking.Level I, prognostic study.
View details for DOI 10.1007/s11999-016-5215-3
View details for PubMedID 28050816
View details for PubMedCentralID PMC5339152
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Predictors of residual disease after unplanned excision of soft tissue sarcomas.
The Journal of surgical research
2017; 208: 26-32
Abstract
Unplanned excision of soft tissue sarcomas (STS) is an important quality of care issue given the morbidity related to tumor bed excision. Since not all patients harbor residual disease at the time of reexcision, we sought to determine predictors of residual STS following unplanned excision.We identified 76 patients from a prospective database (January 1, 2008-September 30, 2014) who received a diagnosis of primary STS following unplanned excision on the trunk or extremities. We used univariable and multivariable analyses to evaluate predictors of residual STS as the primary endpoint. We calculated the sensitivity, specificity, and accuracy of interval magnetic resonance imaging (MRI) to predict residual sarcoma at reexcision.Mean age was 52 y, and 63.2% were male. 50% had fragmented unplanned excision. Among patients undergoing reexcision, residual STS was identified in 70%. On univariable analysis, MRI showing gross disease and fragmented excision were significant predictors of residual STS (odds ratio, 10.59; 95% CI, 2.14-52.49; P = 0.004 and odds ratio, 3.61; 95% CI, 1.09-11.94; P = 0.035, respectively). On multivariable analysis, tumor size predicted distant recurrence and overall survival. When we combined equivocal and positive MRI, the sensitivity and specificity of MRI for predicting residual STS were 86.7% (95% CI, 73.2%-95.0%) and 57.9% (95% CI, 33.5%-79.8%), with an overall accuracy of 78.1% (95% CI, 66.0%-87.5%).About 70% of patients undergoing repeat excision after unplanned excision of STS harbor residual sarcoma. Although interval MRI and fragmented excision appear to be the most significant predictors of residual STS, the accuracy of MRI remains modest, especially given the incidence of equivocal MRI.
View details for DOI 10.1016/j.jss.2016.08.096
View details for PubMedID 27993214
View details for PubMedCentralID PMC5180207
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Influence of IV Contrast Administration on CT Measures of Muscle and Bone Attenuation: Implications for Sarcopenia and Osteoporosis Evaluation.
AJR. American journal of roentgenology
2016; 207 (5): 1046-1054
Abstract
The objective of our study was to characterize enhancement of muscle and bone that occurs on standardized four-phase contrast-enhanced CT.Two musculoskeletal radiologists reviewed standardized four-phase abdominal CT scans obtained with IV contrast material. The psoas area was measured, and the mean attenuation (in Hounsfield units) was recorded for the aorta, psoas muscles, posterior paraspinal muscles, and L4 vertebral body. CT attenuation measures were compared between anatomic regions and imaging phases with the paired t test; associations between measures were examined with the Pearson correlation coefficient (R).The study included 201 patients (97 men, 104 women; mean age, 57.7 ± 12.5 [SD] years). Subject age was inversely correlated with unenhanced attenuation in the psoas muscles, posterior paraspinal muscles, and L4 (p < 0.001). The psoas muscles, posterior paraspinal muscles, and L4 enhanced significantly (p < 0.001) at all three contrast-enhanced phases. The greatest muscle enhancement was observed on delayed phase scans, whereas the greatest enhancement in L4 was seen on portal phase imaging. The unenhanced attenuation of the psoas muscles was significantly and negatively correlated with enhancement of the psoas muscles at the portal and delayed phases (p < 0.05 and p < 0.01, respectively), but these correlations were not seen for the posterior paraspinal muscles. Age was positively correlated with posterior paraspinal muscle enhancement at the portal and delayed phases in men (p < 0.05 and p < 0.01, respectively) but not in women.Contrast enhancement of commonly measured muscle and bone regions is routinely observed and should be considered when using CT attenuation values as biomarkers of sarcopenia and osteoporosis. Furthermore, CT enhancement may be significantly influenced by age, sex, and unenhanced tissue attenuation.
View details for DOI 10.2214/AJR.16.16387
View details for PubMedID 27556335
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Conservative management of desmoid tumors is safe and effective.
journal of surgical research
2016; 205 (1): 115-120
Abstract
Surgical resection of desmoid tumors has traditionally been the mainstay of therapy, but this is a potentially morbid approach with high rates of recurrence. Given increasing reports of active surveillance in this disease, we sought to evaluate our experience with conservative management hypothesizing this would be an effective strategy.Using a prospectively maintained database of sarcoma patients from 2008 to 2015, we identified 47 patients with a diagnosis of desmoid tumor from all anatomic sites. Data points were abstracted on clinical and pathologic factors, disease stability or progression, and follow-up time. Main outcome measurements were tumor recurrence after surgical resection versus tumor progression with conservative management.In our cohort, 20 patients were managed with surveillance, 24 patients with surgery, and three patients with other approaches. Clinical and tumor characteristics between treatment groups were not significantly different. With a median follow-up of 35.7 mo, there was one complete regression, five partial regressions, and 13 stable diseases among the surveillance group. Only one patient under observation progressed, crossing over to surgical resection. Among 24 patients managed with surgery, 13 patients developed local recurrence. Kaplan-Meier analysis revealed a statistically superior progression-free survival in the surveillance group (P = 0.001).This retrospective analysis adds to the growing body of evidence that observation of desmoid tumors is safe and effective with high rates of stable disease. These data further support an initial conservative approach to desmoid tumors that may spare patients the morbidity and risk of recurrence that accompanies potentially extensive operations.
View details for DOI 10.1016/j.jss.2016.06.028
View details for PubMedID 27621007
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MRI findings of serous atrophy of bone marrow and associated complications
EUROPEAN RADIOLOGY
2015; 25 (9): 2771-2778
Abstract
To report the MRI appearance of serous atrophy of bone marrow (SABM) and analyse clinical findings and complications of SABM.A retrospective search of MRI examinations of SABM was performed. Symptoms, underlying conditions, MRI findings, delay in diagnosis and associated complications were recorded.We identified 30 patients (15 male, 15 female; mean age: 46 ± 21 years) with MRI findings of SABM. Underlying conditions included anorexia nervosa (n = 10), cachexia from malignant (n = 5) and non-malignant (n = 7) causes, massive weight loss after bariatric surgery (n = 1), biliary atresia (n = 1), AIDS (n = 3), endocrine disorders (n = 2) and scurvy (n = 1). MRI showed mildly hypointense signal on T1- weighted and hyperintense signal on fat-suppressed fluid-sensitive images of affected bone marrow in all cases and similar signal abnormalities of the adjacent subcutaneous fat in 29/30 cases. Seven patients underwent repeat MRI due to initial misinterpretation of bone marrow signal as technical error. Superimposed fractures of the hips and lower extremities were common (n = 14).SABM occurs most commonly in anorexia nervosa and cachexia. MRI findings of SABM are often misinterpreted as technical error requiring unnecessary repeat imaging. SABM is frequently associated with fractures of the lower extremities.• SABM occurs in several underlying conditions, most commonly anorexia nervosa and cachexia. • Abnormal marrow signal is often misinterpreted as technical error requiring unnecessary repeat imaging. • SABM is frequently associated with stress fractures. • Fractures in SABM can be obscured by marrow signal abnormality on MRI.
View details for DOI 10.1007/s00330-015-3692-5
View details for Web of Science ID 000359396700031
View details for PubMedID 25773942
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Sarcopenia: Current Concepts and Imaging Implications.
AJR. American journal of roentgenology
2015; 205 (3): W255-66
Abstract
The purpose of this article is to review the nomenclature, clinical impact, and diagnostic techniques characterizing sarcopenia.Sarcopenia-defined as significant loss of muscle-is associated with cachexia and frailty. Specific diagnostic criteria for sarcopenia continue to evolve, but imaging can play a role in the detection and quantification of muscle depletion. Emerging evidence indicates that sarcopenia is a relevant predictor of quality and quantity of life, particularly in patients who are elderly, have cancer, or undergo surgery.
View details for DOI 10.2214/AJR.15.14635
View details for PubMedID 26102307
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The Notch of Harty (Pseudodefect of the Tibial Plafond): Frequency and Characteristic Findings at MRI of the Ankle.
AJR. American journal of roentgenology
2015; 205 (2): 358-63
Abstract
The purpose of this study is to report the frequency and characteristic findings of the notch of Harty as seen on MRI.One hundred six consecutive ankle MRI studies performed at 1.5 or 3 T were reviewed retrospectively by two radiologists. Findings relating to the notch of Harty and ankle joint were recorded and analyzed, including qualitative assessment of the presence of the notch, focal chondral thinning or focal subcortical osteosclerosis at the notch, notch width and depth, osteochondral lesions elsewhere in the ankle, subchondral edema signal or cystic change at the tibial plafond, and the presence of an ankle joint effusion.The study group of 106 patients consisted of 48 male and 58 female patients, with a mean age of 44.5 years (SD, 17.5 years). The notch was identified in 48 of 106 patients (45%) (24 male and 24 female patients; mean age, 43.1 years; range, 7-79 years). When present, the notch averaged 6.2 mm (SD, 1.6 mm) in width and 1.2 mm (SD, 0.5 mm) in depth. The notch was graded as prominent in six of the 106 ankle MRI examinations (6%). Subchondral edemalike signal or cystic change was not localized to the notch in any case. Between patients with versus those without a notch, there was no statistically significant difference in age, sex, subjacent subcortical osteosclerosis, ankle joint effusion, osteochondral lesions elsewhere in the ankle, or subchondral bone marrow edema at the tibial plafond.The notch of Harty can be observed as an anatomic variant on MRI and should be differentiated from a traumatic osteochondral lesion.
View details for DOI 10.2214/AJR.14.14012
View details for PubMedID 26204288
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Magnetic resonance imaging of the postoperative meniscus: resection, repair, and replacement.
Magnetic resonance imaging clinics of North America
2014; 22 (4): 517-55
Abstract
Meniscus surgery is common, and surgical indications and techniques continue to evolve. After highlighting relevant anatomy and emerging magnetic resonance (MR) imaging techniques, this article reviews the current indications and techniques used for meniscus surgery, evaluates the use of MR imaging protocols with and without arthrography, and focuses on MR imaging interpretation of the postoperative meniscus, with particular attention to clinical outcomes and diagnostic criteria.
View details for DOI 10.1016/j.mric.2014.07.007
View details for PubMedID 25442022
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Axial scan orientation and the tibial tubercle-trochlear groove distance: error analysis and correction.
AJR. American journal of roentgenology
2014; 202 (6): 1291-6
Abstract
The tibial tubercle (TT)-trochlear groove (TG) distance is an important metric in the assessment of patellofemoral dysfunction and is routinely measured on axial MRI and CT. This study examines error in measurements of the TT-TG distance related to variance in axial MRI scan orientation.Isotropic 3D turbo spin-echo MRI of the extended knee was performed in 12 healthy subjects. The z-axis of the scanner defines the perpendicular to a routine axial plane, and the anatomic axial plane is parallel to the knee joint. Isotropic MRI was reformatted into routine and anatomic axial planes and in axial planes simulating 5° of femoral adduction and abduction relative to the anatomic plane. A method for correcting the TT-TG distance to account for variable axial scan orientation is presented.Five degrees of simulated femoral abduction is associated with a mean increase in the TT-TG distance of 38% (SD = 17%), whereas 5° of simulated femoral adduction is associated with a mean decrease in the TT-TG distance of 51% (SD = 39%). The average deviation of the routine axial plane from the anatomic axial plane was 5.0° abduction (SD = 2.3°). The simplest correction method reduced the mean discrepancy in the observed TT-TG distance by 68% and 72% in simulated femoral abduction and adduction, respectively.The TT-TG distance is sensitive to small changes in femoral alignment and should be interpreted with caution if axial image acquisition is not standardized. Knowing the vertical separation of the TT from the TG facilitates a simplified correction of the TT-TG distance, which is as effective as more complex corrections.
View details for DOI 10.2214/AJR.13.11488
View details for PubMedID 24848827
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Erdheim-Chester disease: an unusual presentation of an uncommon disease.
Skeletal radiology
2014; 43 (6): 835-40
Abstract
Erdheim-Chester disease (ECD) is a rare, non-Langerhans cell histiocytosis with classic radiographic findings of patchy or diffuse osteosclerosis predominantly involving the long bones in a bilaterally symmetrical pattern. A 49-year-old woman presented with diffuse lymphadenopathy, painful skin lesions, and constitutional symptoms. Recent history was significant for a nontraumatic fracture of the tibia 3 weeks prior to admission. Physical examination and laboratory studies were notable for lower extremity pain and swelling, nodular lesions on the skin, and normocytic, normochromic anemia. Plain radiographs showed a lytic pattern of destruction with a superimposed fracture in the left proximal tibia. MRI showed focal bone marrow replacement extending from the subchondral bone to the tibial diaphysis. Excisional lymph node and skin biopsies of the lesions demonstrated a CD-68 positive, S-100 variable, and CD1a-negative histiocytic cell proliferation filling the dermis and completely replacing the sampled lymph node with an accompanying chronic inflammatory infiltrate and fibrosis, pathognomonic for ECD. We report an unusual case of ECD presenting initially as diffuse, painful lymphadenopathy, and subsequently demonstrating a lytic lesion of the tibia underlying a nontraumatic fracture.
View details for DOI 10.1007/s00256-013-1793-2
View details for PubMedID 24366632
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Phase I trial of neoadjuvant conformal radiotherapy plus sorafenib for patients with locally advanced soft tissue sarcoma of the extremity.
Annals of surgical oncology
2014; 21 (5): 1616-23
Abstract
Despite effective local therapy with surgery and radiotherapy (RT), ~50 % of patients with high-grade soft tissue sarcoma (STS) will relapse and die of disease. Since experimental data suggest a significant synergistic effect when antiangiogenic targeted therapies such as sorafenib are combined with RT, we chose to evaluate preoperative combined modality sorafenib and conformal RT in a phase I/II trial among patients with extremity STS amenable to treatment with curative intent.For the phase I trial, eight patients with intermediate- or high-grade STS >5 cm in maximal dimension or low-grade STS >8 cm in maximal dimension received concomitant sorafenib (dose escalation cohort 1:200 twice daily, cohort 2:200/400 daily) and preoperative RT (50 Gy in 25 fractions). Sorafenib was continued during the entire period of RT as tolerated. Surgical resection was completed 4-6 weeks following completion of neoadjuvant sorafenib/RT. Three sorafenib dose levels were planned. Primary endpoints of the phase I trial were maximal tolerated dose and dose-limiting toxicity (DLT).Eight patients were enrolled in the phase I (five females, median age 44 years, two high-grade pleomorphic, two myxoid/round cell liposarcoma, four other). Median tumor size was 16 cm (range 8-29), and all tumors were located in the lower extremity. Two of five patients treated at dose level 2 developed DLT consisting of grade 3 rash not tolerating drug reintroduction. Other grade 3 side effects included anemia, perirectal abscess, and supraventricular tachycardia. Radiation toxicity (grade 1 or 2 dermatitis; N = 8) and post-surgical complications (three grade 3 wound complications) were comparable to historical controls and other series of preoperative RT monotherapy. Complete pathologic reponse (≥95 % tumor necrosis) was observed in three patients (38 %).Neoadjuvant sorafenib in combination with RT is tolerable and appears to demonstrate activity in locally advanced extremity STS. Further study to determine efficacy at dose level 1 is warranted. (ClinicalTrials.gov identifier NCT00805727).
View details for DOI 10.1245/s10434-014-3543-7
View details for PubMedID 24554062
View details for PubMedCentralID PMC4153793
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Real-time magnetic resonance imaging (MRI) during active wrist motion--initial observations.
PloS one
2013; 8 (12): e84004
Abstract
Non-invasive imaging techniques such as magnetic resonance imaging (MRI) provide the ability to evaluate the complex anatomy of bone and soft tissues of the wrist without the use of ionizing radiation. Dynamic instability of wrist--occurring during joint motion--is a complex condition that has assumed increased importance in musculoskeletal medicine. The objective of this study was to develop an MRI protocol for evaluating the wrist during continuous active motion, to show that dynamic imaging of the wrist is realizable, and to demonstrate that the resulting anatomical images enable the measurement of metrics commonly evaluated for dynamic wrist instability.A 3-Tesla "active-MRI" protocol was developed using a bSSFP sequence with 475 ms temporal resolution for continuous imaging of the moving wrist. Fifteen wrists of 10 asymptomatic volunteers were scanned during active supination/pronation, radial/ulnar deviation, "clenched-fist", and volarflexion/dorsiflexion maneuvers. Two physicians evaluated distal radioulnar joint (DRUJ) congruity, extensor carpi ulnaris (ECU) tendon translation, the scapholunate (SL) interval, and the SL, radiolunate (RL) and capitolunate (CL) angles from the resulting images.The mean DRUJ subluxation ratio was 0.04 in supination, 0.10 in neutral, and 0.14 in pronation. The ECU tendon was subluxated or translated out of its groove in 3 wrists in pronation, 9 wrists in neutral, and 11 wrists in supination. The mean SL interval was 1.43 mm for neutral, ulnar deviation, radial deviation positions, and increased to 1.64 mm during the clenched-fist maneuver. Measurement of SL, RL and CL angles in neutral and dorsiflexion was also accomplished.This study demonstrates the initial performance of active-MRI, which may be useful in the investigation of dynamic wrist instability in vivo.
View details for DOI 10.1371/journal.pone.0084004
View details for PubMedID 24391865
View details for PubMedCentralID PMC3877133
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MRI of snow skiing and snowboarding injuries.
Seminars in musculoskeletal radiology
2005; 9 (4): 360-78
Abstract
Snow skiing has been called "the world's oldest sport," "the fastest non-motorized sport on Earth," and "the riskiest sport undertaken by adults on a routine basis." This article discusses the common mechanisms for orthopedic injuries occurring in two of the most popular winter sports in the world that have a reputation for an inherently high risk of injury: alpine skiing and snowboarding. The emphasis herein is on magnetic resonance imaging of characteristic injuries in skiers (knee, thumb, shoulder) and in snowboarders (wrist, forearm, ankle). Spine injuries in snowboarders and skiers are also discussed.
View details for DOI 10.1055/s-2005-923380
View details for PubMedID 16315118
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Presumptive subarticular stress reactions of the knee: MRI detection and association with meniscal tear patterns.
Skeletal radiology
2004; 33 (5): 260-4
Abstract
MRI detects subchondral marrow findings in painful knees which bear resemblance to spontaneous osteonecrosis of the knee (SONK). Gathering evidence suggests that the primary or predominant pathogenesis of these lesions is physical stress. This study analyzes the patient characteristics and meniscal pathology associated with these lesions-herein referred to as "presumptive subarticular stress related" (PSSR) lesions.All patients were scanned using a standardized imaging protocol. The criterion for a PSSR lesion was a subchondral marrow edema pattern encompassing a more focal, low-signal zone adjacent to or contiguous with the subchondral cortex. Patients were identified using an electronic database search of cases reported by one experienced musculoskeletal radiologist.Twenty-five PSSR lesions were identified among 1948 MRI evaluations of the knee. Twenty-one PSSR lesions occurred in the medial compartment, and four occurred in the lateral compartment. There was no sex predilection. Patients with PSSR lesions were older than other patients undergoing MRI evaluation (mean 66 years versus 52 years, P<0.001). Meniscal tears occurred more commonly in cases with PSSR lesions than in the group as a whole (76% versus 45%, P<0.001). Radial and posterior root tears were more common in knees with PSSR lesions than in other knees with meniscal tears (53% versus 26%, P<0.01).PSSR lesions are associated with meniscal tears and, more specifically, with meniscal tear patterns that dramatically increase contact forces across the knee joint. This observation supports the hypothesis that mechanical stress is important in the pathogenesis of these subarticular lesions that are detected by MRI.
View details for DOI 10.1007/s00256-004-0751-4
View details for PubMedID 14999432
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MR imaging of sports-related hip disorders.
Magnetic resonance imaging clinics of North America
2003; 11 (2): 255-81
Abstract
Hip arthroscopy is being used increasingly for the diagnosis and treatment of hip disorders. MR imaging performed with appropriate technical considerations may aid not only in preoperative planning but in the appropriate selection of patients, which tends to lead to better postoperative results. Although the painful hip is imaged most commonly by radiography, MR imaging is considered the next imaging test of choice for evaluation of most common hip abnormalities in athletes, including labral injuries, ligament injuries, osteochondral injuries, fractures, bursitis, and musculotendinous injuries. MR arthrography can be a particularly useful technique for dedicated assessment of hip joint internal derangements.
View details for DOI 10.1016/s1064-9689(03)00029-1
View details for PubMedID 12916890
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MR imaging features of osteochondritis dissecans of the femoral sulcus.
AJR. American journal of roentgenology
2003; 180 (3): 641-5
Abstract
The objective of this study was to describe the MR imaging features of osteochondritis dissecans of the femoral sulcus, which have not been described previously.Osteochondritis dissecans of the femoral sulcus has been recognized as a unique clinical and radiographic entity, warranting early diagnosis and appropriate treatment. Although this type of osteochondritis dissecans may be inconspicuous on radiography, fast spin-echo proton density-weighted and T2-weighted MR imaging sequences allow evaluation for articular cartilage integrity and lesion stability. Because of the orientation of the femoral sulcus, osteochondritis dissecans involving the femoral sulcus is best evaluated on axial and sagittal images.
View details for DOI 10.2214/ajr.180.3.1800641
View details for PubMedID 12591666
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Spinous process fractures associated with Baastrup disease.
Clinical imaging
2002; 28 (3): 219-22
Abstract
Patients with Baastrup disease may experience pain owing to irritation of the periosteum or adventitial bursae between abutting spinous processes. We are not aware of any reports in the literature that describe stress fractures of the spinous fractures in patients with Baastrup disease. In this case report, we present two cases of spinous process fractures in lumbar vertebrae associated with Baastrup disease and describe their appearance with conventional radiography, bone scintigraphy, computed tomography (CT) and magnetic resonance (MR) imaging.
View details for DOI 10.1016/S0899-7071(03)00156-6
View details for PubMedID 15158230
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Imaging of sports-related muscle injuries.
Radiologic clinics of North America
2002; 40 (2): 333-62, vii
Abstract
Muscle derangements in athletes have a wide variety of causes, treatments, and prognoses. Given that the cause and severity of sports-related injuries may be difficult to determine clinically in some cases, MR imaging is utilized increasingly to evaluate muscle injuries in athletes. After reviewing useful MR imaging techniques, this article focuses on MR imaging of the most common causes of muscle pain and disability in athletes, including myotendinous strain, delayed onset muscle soreness, muscle contusion, myositis ossificans, muscle laceration, muscle herniation, and compartment syndrome. The differential diagnosis of various signal intensity abnormalities in muscle also is reviewed.
View details for DOI 10.1016/s0033-8389(02)00008-8
View details for PubMedID 12118828
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Postoperative magnetic resonance imaging of articular cartilage repair.
Seminars in musculoskeletal radiology
2001; 5 (4): 345-63
Abstract
The treatment of articular cartilage injuries remains a challenge because cartilage has a limited capacity for spontaneous repair. Over the past decade, a number of surgical interventions have been developed to produce a durable repair. This article reviews the available treatment options, including their indications, technique, and clinical results, and illustrates the MR imaging appearance of normal repair sites and postoperative complications.
View details for DOI 10.1055/s-2001-19044
View details for PubMedID 11745050
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Magnetic resonance imaging of the peripheral nervous system.
Physical medicine and rehabilitation clinics of North America
2001; 12 (2): 399-432
Abstract
An accurate diagnosis is the essential first step toward a successful treatment plan in patients who present with pain and suspected nerve entrapment. Pain and dysfunction are often related to an acute traumatic event or a classic presentation that leads to a straightforward clinical diagnosis. The diagnostic approach to abnormalities of the peripheral nervous system always begins with a thorough history and physical examination. Imaging may play an important role in confirming the initial clinical [figure: see text] diagnosis so that a rational plan of treatment may be selected. Diagnostic imaging is especially important when there is significant uncertainty regarding the cause of pain and the outcome may be improved by timely implementation of various treatment options. Diagnostic accuracy is important when various conditions in the differential diagnosis would be treated differently from the beginning. Indeed, certain conditions that result in pain and dysfunction related to peripheral nerve entrapment are best treated with initial rest, protection, and rehabilitation whereas other conditions are best treated with prompt surgery. Promptly arriving at an accurate diagnosis is an essential step in designing a rational course of therapy, in achieving a good outcome, and in treating medical conditions in a timely fashion. Indeed, because pain is mediated through peripheral nerves, establishing an accurate diagnosis is especially important in disorders of the peripheral nervous system in which there may be considerable pain and suffering with an incorrect or delayed diagnosis. Moreover, an early diagnosis is desirable [figure: see text] to preserve motor power and sensory function in cases of clinically occult nerve entrapment. Although entrapment syndromes are well described and widely documented in the literature, they may be easily missed in clinical practice in certain instances. Although MR imaging is useful to confirm and characterize a known or suspected case of peripheral nerve entrapment, there may be evidence of peripheral nerve pathology that is first detected with MR imaging. Clinically unsuspected nerve entrapment may occur in patients with occult dorsal ganglion cysts in the wrist that may entrap the posterior interosseous nerve and produce pain without other symptoms. In addition, the authors routinely see patients with paralabral cysts secondary to tears of the superior labrum in the shoulder resulting in entrapment of the suprascapular nerve. This diagnosis is usually not suspected clinically until there is relatively advanced weakness and muscular atrophy in addition to shoulder pain. MR imaging remains an evolving technique with ongoing improvements in technology and developing clinical experience, resulting in greater diagnostic capacity. In this article current technique and strategies for image analysis and the authors' specific clinical experience with MR imaging of peripheral nerve disorders are reviewed. The exact role of MR imaging in the evaluation of these disorders will be further defined with additional experimental work and published clinical experience.
View details for PubMedID 11345015
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Shell osteochondral allografts of the knee: comparison of mr imaging findings and immunologic responses.
Radiology
2001; 219 (1): 35-43
Abstract
To define the magnetic resonance (MR) imaging appearance of shell osteochondral allografts of the knee and compare the MR findings with antibody responses.Thirty-six grafts were evaluated with a 1.5-T unit with T1-, intermediate-, and T2-weighted, and three-dimensional spoiled gradient-recalled MR imaging at 3, 6, 12, 24, and/or 36 months after surgery. Nineteen patients underwent imaging serially. Two osteoradiologists scored by consensus host marrow edema, thickness of graft-host interface, signal intensity of graft marrow, cyst formation, joint effusion, articular cartilage defects, and surface collapse. Patients were divided into antibody-positive (AP) (n = 11) and antibody-negative (AN) (n = 25) groups evenly distributed across the different time points on the basis of results of anti-human leukocyte antigen antibody screening. MR findings for the two groups were compared.AP patients demonstrated greater mean edema (P<.002), thicker interface (P<.03), and more abnormal graft marrow (P<.04) than AN patients, and they had a higher proportion of surface collapse (P<.03).Humoral immune responses were associated with more inflammation and less complete incorporation after allograft placement. MR imaging shows promise as a surrogate biomarker for success of shell osteochondral allograft implantation.
View details for DOI 10.1148/radiology.219.1.r01ap0435
View details for PubMedID 11274532
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Protocol issues for delayed Gd(DTPA)(2-)-enhanced MRI (dGEMRIC) for clinical evaluation of articular cartilage.
Magnetic resonance in medicine
2001; 45 (1): 36-41
Abstract
Biochemical and histologic data have validated the technique of delayed gadolinium-enhanced MRI, in which the T(1) values of cartilage after penetration of Gd(DTPA)2-allow assessment of the glycosaminoglycan (GAG) component of articular cartilage. This work describes the factors that have been found to be important for the practical implementation of the technique: 1) Exercise immediately after intravenous contrast administration was necessary for effective penetration of the contrast into the articular cartilage; 2) double-dose contrast was better than single-dose; 3) after contrast administration, a time window of 30-90 min for the hip, and 2-3 hr for all compartments of the knee proved to be appropriate for assessing articular cartilage; and 4) in some cases of hypointensities in the subchondral patellar bone, decreased penetration of the contrast agent into cartilage from bone was found. With the protocol described, ROIs on T(1) images were reproducible within 15% on two separate imaging sessions, and initial clinical studies demonstrated the possible applications of the technique. Magn Reson Med 45:36-41, 2001.
View details for DOI 10.1002/1522-2594(200101)45:1<36::aid-mrm1006>3.0.co;2-w
View details for PubMedID 11146483
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Polydioxanone biodegradable pins in the knee: MR imaging.
AJR. American journal of roentgenology
2001; 176 (1): 83-90
Abstract
Biodegradable solid implants have been developed as an alternative to metallic orthopedic fixation. In animal models, implants degrade within and are replaced by bone. This study documents the resorption of these devices in human patients with MR imaging.One hundred seventy-five 1.3-mm biodegradable pins made of polydioxanone were used to secure a total of 59 osteochondral allografts of the knee. Patients with the pins underwent scanning on a 1.5-T unit with 3.3- to 4-mm contiguous T1-weighted spin-echo (TR/TE, 600/15), fat-saturated proton density-weighted (3000/40), T2-weighted fast spin-echo (3000/63), and three-dimensional spoiled gradient-recalled (47/7; flip angle, 60 degrees ) sequences at 3, 6, 12, 24, or 36 months after surgery. Eighty-nine pins were imaged on multiple occasions. Two osteoradiologists interpreted the MR examinations.More than 80% of the pin channels were visible at 3 and at 6 months after surgery. By 24 months, only 20% of the pin channels were visible, with the remainder having been replaced by bone. At 3 months, nearly 40% of the pins were associated with adjacent marrow edema. Edema generally diminished, involving less than 20% of pins at later time points. Focal cartilage defects were evident at 32% of the pin insertion sites during the first 6 months, but these defects were present in only 4% of the insertion sites thereafter.Biodegradable polydioxanone pins usually resorb completely by 24 months. Marrow edema, presumably representing inflammation related to pin resorption, is infrequent and tends to resolve. Cartilage defects related to pin placement heal spontaneously.
View details for DOI 10.2214/ajr.176.1.1760083
View details for PubMedID 11133543
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Pulley system in the fingers: normal anatomy and simulated lesions in cadavers at MR imaging, CT, and US with and without contrast material distention of the tendon sheath.
Radiology
2000; 217 (1): 201-12
Abstract
To describe the normal anatomy of the finger flexor tendon pulley system, with anatomic correlation, and to define criteria to diagnose pulley abnormalities with different imaging modalities.Three groups of cadaveric fingers underwent computed tomography (CT), magnetic resonance (MR) imaging, and ultrasonography (US). The normal anatomy of the pulley system was studied at extension and flexion without and with MR tenography. Pulley lengths were measured, and anatomic correlation was performed. Pulley lesions were created and studied at flexion, extension, and forced flexion. Two radiologists reviewed the studies in blinded fashion.MR imaging demonstrated A2 (proximal phalanx) and A4 (middle phalanx) pulleys in 12 (100%) of 12 cases, without and with tenography. MR tenography showed the A3 (proximal interphalangeal) and A5 (distal interphalangeal) pulleys in 10 (83%) and nine (75%) cases, respectively. US showed the A2 pulley in all cases and the A4 pulley in eight (67%). CT did not allow direct pulley visualization. No significant differences in pulley lengths were measured at MR, US, or pathologic examination (P: =.512). Direct lesion diagnosis was possible with MR imaging and US in 79%-100% of cases, depending on lesion type. Indirect diagnosis was successful with all methods with forced flexion.MR imaging and US provide means of direct finger pulley system evaluation.
View details for DOI 10.1148/radiology.217.1.r00oc40201
View details for PubMedID 11012445
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Characterization of the "red zone" of knee meniscus: MR imaging and histologic correlation.
Radiology
2000; 217 (1): 193-200
Abstract
To determine the extent and vascularity of knee menisci with conventional and gadolinium-enhanced magnetic resonance (MR) imaging in cadaveric specimens, with histologic findings as the reference standard, and to investigate signal intensity changes in menisci and perimeniscal soft tissues in symptomatic patients.Radial dimensions and enhancement patterns of menisci were recorded and compared in (a) 12 cadaveric menisci examined with conventional and gadolinium-enhanced intermediate-weighted and fat-suppressed T1-weighted spin-echo MR imaging, high-spatial-resolution T1-weighted and fast low-angle shot MR imaging, and gross anatomic and histologic specimens and (b) 18 patients examined with conventional and gadolinium-enhanced fat-suppressed T1-weighted spin-echo MR imaging.No differences in radial measurements of the meniscus were found for different MR techniques (P =.551). Despite the presence of vessels in the peripheral 10%-15% of the menisci, no enhancement of menisci was detected in specimens or patients. Perimeniscal soft-tissue enhancement adjacent to the posterior horn was greater than that adjacent to the anterior horn (P <.05), and enhancement of the lateral meniscal body was greater than that of the medial meniscal body (P <.05).The wedge-shaped low-signal-intensity structure seen on MR images represents the entire meniscus. Intravenous injection of contrast material does not appear to be useful for differentiation of the vascularized from the nonvascularized zone of the meniscus.
View details for DOI 10.1148/radiology.217.1.r00se36193
View details for PubMedID 11012444
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MR imaging of degenerative diseases in the cervical spine.
Magnetic resonance imaging clinics of North America
2000; 8 (3): 471-90
Abstract
This article reviews three topics of fundamental importance in MR imaging of degenerative diseases in the cervical spine: (1) common clinical presentations that determine whether an MR examination is ordered and the ultimate significance ascribed to MR imaging results; (2) imaging techniques; and (3) MR imaging of the major types of cervical spine degeneration.
View details for PubMedID 10947922
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Calcium pyrophosphate dihydrate crystal deposition in and around the atlantoaxial joint: association with type 2 odontoid fractures in nine patients.
Radiology
2000; 216 (1): 213-9
Abstract
To investigate the histopathologic anatomy of calcium pyrophosphate dihydrate (CPPD) crystal deposition in and around the atlantoaxial joint and the association between CPPD crystal deposition and subchondral cysts, erosions, and fracture involving the odontoid process of the axis.One adult cadaver demonstrating calcification in the retro-odontoid area at computed tomography (CT) was selected for further radiography, CT, and magnetic resonance (MR) imaging at the C1-2 level. Anatomic sectioning and histologic evaluations were performed in the specimen. For clinical study, radiographs (n = 5), CT scans (n = 8), and MR images (n = 6) in nine patients (mean age, 74.4 years) with odontoid process fractures and CPPD crystal deposits in and around the atlantoaxial joint were reviewed.In the cadaveric specimen, radiography and CT demonstrated calcifications in the transverse ligament; histologic evaluation confirmed that these calcifications were CPPD crystal deposits. In all nine patients, radiography (n = 5) and CT (n = 8) also showed calcification in areas adjacent to the odontoid process, which included the transverse ligament. T1- and T2-weighted MR imaging showed a retro-odontoid mass of low signal intensity that compressed the cervical cord in six patients. CT, MR imaging, or both demonstrated subchondral cysts, osseous erosions, or a type 2 odontoid fracture in all patients.CPPD crystal deposition disease involving the C1-C2 articulation can be a clinically important entity that may place affected patients at increased risk of pathologic fracture of the odontoid process.
View details for DOI 10.1148/radiology.216.1.r00jl36213
View details for PubMedID 10887250
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Stress fractures of the lateral metatarsal bones in metatarsus adductus foot deformity: a previously unrecognized association.
Skeletal radiology
1999; 28 (12): 679-84
Abstract
To document a distinctive pattern of stress fractures in the lateral metatarsal bones of patients with metatarsus adductus foot deformity.Conventional radiographs and available medical records were reviewed in 11 patients (6 women, 5 men; ages 25-61 years) with stress fractures of the lateral (fourth or fifth) metatarsal bones and metatarsus adductus. Evaluation included the number and location of fracture(s), forefoot adduction angle, and qualitative assessment of bone mineral density. Conditions that might predispose patients to metatarsal fractures, including direct trauma, osteoporosis, and neuropathic osteoarthropathy were also recorded.A total of 22 stress fractures were demonstrated, 17 of which involved the lateral metatarsals. A solitary fracture was present in six patients, while multiple fractures were evident in five patients. The sites of involvement were the fifth metatarsal (n=10), fourth metatarsal (n=7), third metatarsal (n=3), second metatarsal (n=1), and first metatarsal (n=1) bones. The locations of the stress fractures were in the proximal one-third of the metatarsal bones in 19 instances (86%) and in the middle one-third in three instances (14%). Forefoot adduction angle measured between 21 degrees and 37 degrees (normal range 8 degrees -14 degrees).Patients with metatarsus adductus may be at increased risk for stress fractures involving the lateral metatarsal bones, likely owing to the presence of altered biomechanics that place greater loads across the lateral aspect of the foot.
View details for DOI 10.1007/s002560050573
View details for PubMedID 10653362
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Evaluation of the postoperative meniscus of the knee: a study comparing conventional arthrography, conventional MR imaging, MR arthrography with iodinated contrast material, and MR arthrography with gadolinium-based contrast material
SKELETAL RADIOLOGY
1999; 28 (9): 508-514
Abstract
To compare four imaging methods in the evaluation of the postoperative meniscus: conventional arthrography, conventional MR imaging, MR arthrography with iodinated contrast material, and MR arthrography with gadolinium-based contrast material.Thirty-three patients referred for knee MR examinations with a history of meniscal surgery were studied prospectively. At the first patient visit, conventional MR examination was followed by an MR arthrogram with gadolinium-based contrast material. At the second visit, a conventional arthrogram with iodinated contrast material was followed immediately by an MR examination. Imaging examinations were interpreted by a masked reader, and then compared with the results of repeat arthroscopic surgery in 12 patients.The correct evaluation of the status of postoperative menisci was allowed in 12 of 13 patients (92%) by MR arthrography using gadolinium-based contrast agent, 10 of 13 patients (77%) by conventional MR examination, 9 of 12 patients (75%) by MR arthrography, and 7 of 12 patients (58%) by conventional arthrography.Intra-articular fluid is advantageous in the evaluation of patients with a suspected meniscal retear. MR arthrography with gadolinium-based contrast material is the most accurate imaging method for the diagnosis of meniscal retears.
View details for Web of Science ID 000083001300003
View details for PubMedID 10525794
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Iliotibial band friction syndrome: MR imaging findings in 16 patients and MR arthrographic study of six cadaveric knees
RADIOLOGY
1999; 212 (1): 103-110
Abstract
To define magnetic resonance (MR) imaging findings in patients with the iliotibial band friction syndrome (ITBFS) and to correlate these findings with anatomic features defined at magnetic resonance (MR) arthrography in cadavers.The anatomic relationship of the iliotibial tract (ITT) to the lateral recesses of the knee joint and the lateral femoral epicondyle was investigated with MR arthrography at full extension and at 30 degrees and 60 degrees of knee flexion in six cadaveric knees. Seventeen MR imaging studies in 16 patients with ITBFS were evaluated.In the cadaveric study, no interference of the lateral synovial recess with the lateral femoral epicondyle at full extension and at 30 degrees and 60 degrees of knee flexion was observed. In all specimens, correlation of MR images with macroscopic and microscopic sections revealed no primary bursa between the lateral femoral epicondyle and the ITT. In clinical studies, MR imaging findings of poorly defined signal intensity abnormalities or circumscribed fluid collections were located in a compartmentlike space confined laterally by the ITT and medially by the meniscocapsular junction, the lateral collateral ligament, and the lateral femoral epicondyle.MR imaging accurately depicts the compartmentlike distribution of signal intensity abnormalities in patients with ITBFS.
View details for Web of Science ID 000081086900017
View details for PubMedID 10405728
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Bicipitoradial bursitis: MR imaging findings in eight patients and anatomic data from contrast material opacification of bursae followed by routine radiography and MR imaging in cadavers.
Radiology
1999; 212 (1): 111-6
Abstract
To use radiography and magnetic resonance (MR) imaging after contrast material opacification of the bursae in cadaveric specimens to demonstrate the anatomy of the bicipitoradial bursa and to report MR imaging findings in patients with bicipitoradial bursitis.Bicipitoradial bursa in eight cadaveric elbows were injected with a solution containing gadodiamide, iodinated contrast agent, and gelatin. Radiographs and MR images were obtained in each specimen, with both supination and pronation of the forearm. The morphology and relationships of the bursa were studied. Anatomic sections subsequently were obtained. MR imaging studies in eight patients with bicipitoradial bursitis were also evaluated.The bicipitoradial bursa revealed a smooth outline and a wide base along the superficial aspect of the radius. The mean volume of contrast material that could be injected before extravasation was 4 mL. The mean size of the bursa was 1.8 x 2.5 cm. The bicipitoradial bursa enveloped the biceps tendon, with internal septation seen in two cases. Displacement of the superficial branch of the radial nerve by the bursa was found in two specimens. Communication between the bicipitoradial bursa and elbow joint was not observed. In patients, MR imaging demonstrated fluid collections in the bicipitoradial bursa in all cases, with compression of branches of the radial nerve in two cases.The anatomy of the bicipitoradial bursa is demonstrated with radiography and MR imaging of bursae. MR imaging allows accurate diagnosis of bicipitoradial bursitis and its effects on adjacent structures.
View details for DOI 10.1148/radiology.212.1.r99jl49111
View details for PubMedID 10405729
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Tophaceous pseudogout of the sternoclavicular joint.
AJR. American journal of roentgenology
1999; 172 (6): 1587-9
View details for DOI 10.2214/ajr.172.6.10350294
View details for PubMedID 10350294
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Post-traumatic and stress-induced osteolysis of the distal clavicle: MR imaging findings in 17 patients.
Skeletal radiology
1999; 28 (4): 202-8
Abstract
To describe the MR imaging findings in patients with osteolysis of the distal clavicle and to compare the MR imaging appearance of clavicular osteolysis following acute injury with that related to chronic stress.MR imaging examinations were reviewed in 17 patients (14 men, 3 women; ages 16-55 years) with the diagnosis of post-traumatic or stress-induced osteolysis of the clavicle. A history of a single direct injury was present in seven patients and a history of weight-lifting, participation in sports, or repetitive microtrauma was present in 10 patients.MR imaging showed edema in the distal clavicle in 17 patients and, of these, eight also had edema in the acromion. The edema was most evident in STIR and fat-suppressed T2-weighted pulse sequences. Other findings about the acromioclavicular (AC) joint were prominence of the joint capsule in 14, joint fluid in eight, cortical irregularity in 12, and bone fragmentation in six patients. No differences in the MR imaging features of post-traumatic and stress-induced osteolysis of the distal clavicle were observed.Post-traumatic and stress-induced osteolysis of the distal clavicle have similar appearances on MR imaging, the most common and conspicuous MR imaging feature being increased T2 signal intensity in the distal clavicle.
View details for DOI 10.1007/s002560050501
View details for PubMedID 10384990
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Magnetic resonance imaging of knee cartilage repair.
Topics in magnetic resonance imaging
1998; 9 (6): 377-392
Abstract
Cartilage injury resulting in osteoarthritis is a frequent cause of disability in young people. Osteoarthritis, based on either cartilage injury or degeneration, is a leading cause of disability in the United States. Over the last several decades, much progress has been made in understanding cartilage injury and repair. Magnetic resonance (MR) imaging, with its unique ability to noninvasively image and characterize soft tissue, has shown promise in assessment of cartilage integrity. In addition to standard MR imaging methods, MR imaging contrast mechanisms under development may reveal detailed information regarding the physiology and morphology of cartilage. MR imaging will play a crucial role in assessing the success or failure of therapies for cartilage injury and degeneration.
View details for PubMedID 9894740
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Complications in Paget disease at MR imaging.
Radiology
1998; 209 (3): 641-51
Abstract
To determine the MR imaging findings in patients with complications of Paget disease of bone.Of 45 patients with Paget disease who underwent MR imaging, 33 (26 men, seven women; age range, 64-91 years) with known complications of the disease were examined. Imaging in this subgroup included radiography (n = 26), computed tomography (n = 12), bone scintigraphy (n = 15), and magnetic resonance (MR) imaging (n = 33). Patients were examined specifically for musculoskeletal and neurologic complications of Paget disease, including fracture, basilar impression, spinal stenosis, bone tumor, and osteoarthrosis.The 56 complications documented in the 33 patients were fracture (n = 17), neurologic entrapment (n = 19), neoplasm (n = 9), and arthropathy (n = 11). MR imaging was beneficial in the diagnostic evaluation of basilar impression (n = 7), spinal stenosis (n = 12), and the tumor stage (n = 9). It also helped to successfully evaluate pagetic bone narrowing of the coracoacromial arch, which was associated with impingement syndrome and rotator cuff rupture (n = 2). The signal intensities in pagetic bone were most commonly similar to those in fat; this finding had a 100% negative predictive value in excluding neoplasm.Although Paget disease is diagnosed economically with conventional radiography, MR imaging is well suited for demonstrating the presence and extent of several characteristic disease complications, including basilar impression, spinal stenosis, and secondary neoplasm.
View details for DOI 10.1148/radiology.209.3.9844654
View details for PubMedID 9844654
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Disorders in the stumps of amputee patients: MR imaging.
AJR. American journal of roentgenology
1998; 171 (2): 497-501
View details for DOI 10.2214/ajr.171.2.9694483
View details for PubMedID 9694483
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Normal Anatomy of the Elbow on Conventional MR Imaging and MR Arthrography.
Seminars in musculoskeletal radiology
1998; 2 (2): 133-140
Abstract
Conventional MR imaging allows clear depiction of the muscles, tendons, nerves, vessels, ligaments, bones, and cartilage that compose the elbow. MR arthrography can be a valuable supplementary technique for optimizing evaluation of intraarticular structures, including the undersurfaces of the collateral ligaments. Regardless of the imaging technique utilized, knowledge of normal anatomy-and normal anatomic variants-is fundamental for accurate assessment of normal and diseased states.
View details for DOI 10.1055/s-2008-1080094
View details for PubMedID 11387096
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The SAPHO syndrome: an evolving concept for unifying several idiopathic disorders of bone and skin.
AJR. American journal of roentgenology
1998; 170 (3): 585-91
View details for DOI 10.2214/ajr.170.3.9490935
View details for PubMedID 9490935
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Update on imaging of orthopedic infections.
The Orthopedic clinics of North America
1998; 29 (1): 41-66
Abstract
Although the diagnosis of infection is only a small part of the orthopedist's job description, it is a important part. This article discusses the fundamentals of orthopedic infections and highlights the refinements on this topic from a radiologic perspective. In addition to reviewing the imaging appearance of musculoskeletal infections in bone and the surrounding soft tissues, we focus on the advantages and disadvantages of five imaging methods: radiography, sonography, CT, scintigraphy, and MR imaging. Finally, we review three specific situations that have garnered substantial attention in recent medical literature: chronic recurrent multifocal osteomyelitis, musculoskeletal infections in AIDS patients, and pedal infections in diabetic patients.
View details for DOI 10.1016/s0030-5898(05)70006-7
View details for PubMedID 9405777
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Glycosaminoglycan in articular cartilage: in vivo assessment with delayed Gd(DTPA)(2-)-enhanced MR imaging.
Radiology
1997; 205 (2): 551-8
Abstract
To investigate the feasibility of applying magnetic resonance (MR) imaging with use of an anionic compound, Gd(DTPA)2- (gadolinium diethylenetriamine-pentaacetic acid), for measuring glycosaminoglycan concentration in human cartilage in clinical studies.Penetration of Gd(DTPA)2- into cartilage was monitored through sequential T1-calculated images obtained after intraarticular (n = 2) or intravenous (n = 2) injection. T1-weighted and T1-calculated image series were then obtained in seven volunteers (nine knees) after penetration of Gd-(DTPA)2- into cartilage. If T1 was heterogeneous on Gd(DTPA)(2-)-enhanced images, images were also obtained after penetration of the cartilage with the nonionic contrast agent, gadoteridol.Gd(DTPA)2- penetrated cartilage from the articular surface after intraarticular injection and from both the articular surface and the subchondral bone after intravenous injection. The latter resulted in shorter overall penetration time. T1 values on Gd(DTPA)(2-)-enhanced images were homogeneous in four knees, but in five knees T1 differences of up to 30% were observed. These T1 differences were not seen in the presence of gadoteridol. These variations in T1 reflected about 50% variations in glycosaminoglycan.The data suggest that Gd(DTPA)(2-)-enhanced MR imaging has potential for monitoring glycosaminoglycan content of cartilage in vivo.
View details for DOI 10.1148/radiology.205.2.9356644
View details for PubMedID 9356644
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MR imaging of arthritides affecting the shoulder.
Magnetic resonance imaging clinics of North America
1997; 5 (4): 861-79
Abstract
MR imaging has had a limited role in the evaluation of arthritis involving the shoulder, despite studies that have shown this technique to be more sensitive than radiography in the evaluation of osseous erosions and cartilage loss. Factors responsible for limiting the use of MR imaging are its relatively high cost, as well as its insensitivity to diminished osseous mineralization and subtle areas of calcification or hyperostosis. MR imaging findings of some arthropathies, however--such as synovial osteochondromatosis, PVNS, and amyloid arthropath--are highly characteristic, and help in determining both diagnosis and treatment. Physicians also should be aware that MR imaging is highly effective at diagnosing numerous "secondary" conditions common in patients with shoulder arthropathies, including rotator cuff rupture, synovial cyst formation, and osteonecrosis.
View details for PubMedID 9314511
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Short echo time projection reconstruction MR imaging of cartilage: Comparison with fat-suppressed spoiled GRASS and magnetization transfer contrast MR imaging
RADIOLOGY
1997; 203 (2): 501-507
Abstract
To evaluate short echo time (TE) projection reconstruction magnetic resonance (MR) imaging in the detection of cartilage lesions.Twenty-seven cartilage regions of 10 human patellar specimens were examined with the following MR sequences: short TE projection reconstruction (repetition time msec/TE msec, 400/0.15), fat-suppressed three-dimensional spoiled gradient-recalled acquisition in the steady state (Spoiled GRASS) (50/10, 60 degrees flip angle), and magnetization transfer contrast (MTC) subtraction (400/6). MR findings were correlated with histopathologic grading of the cartilage.For detection of cartilage lesions, sensitivity of projection reconstruction imaging (100%) was significantly greater (P = .03) than that of MTC (62%) but not significantly greater (P > .05) than that of Spoiled GRASS (81%) imaging. Accuracy of projection reconstruction was significantly greater than that of MTC (P = .004) and Spoiled GRASS (P = .03) imaging. Unmasking of collagen fibers was most predictive of abnormal signal intensity of the cartilage with all sequences.In vitro, short TE projection reconstruction MR imaging provides superior delineation of cartilage lesions when compared with two other sequences. On Spoiled GRASS and MTC images, signal intensity of the superficial layer of cartilage is not a reliable sign for surface integrity.
View details for Web of Science ID A1997WU53200041
View details for PubMedID 9114112
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Intraosseous venous drainage anomaly in patients with pretibial varices: imaging findings.
Radiology
1997; 202 (3): 751-7
Abstract
To determine a set of distinctive imaging findings seen in symptomatic patients with pretibial varices.Medical records and imaging studies of patients who presented with pretibial varices over an 8-year period were collected from four institutions. Findings in six symptomatic patients with pretibial varices were retrospectively reviewed. Radiographic and magnetic resonance (MR) imaging findings were available from all six patients; findings from several other modalities were also available in some patients.Conventional radiographs showed a small osteolytic defect in the anterior cortex of the midtibia and a prominent, longitudinally oriented, radiolucent groove in the proximal half of the tibial diaphysis. MR images showed pretibial varices connected to an enlarged vessel in the tibia that eventually exited through the nutrient foramen. Computed tomographic (three patients), sonographic (four patients), venographic (four patients), arteriographic (two patients), and surgical (three patients) findings demonstrated that these patients had an unusual intraosseous varix that traversed the anterior cortex, medullary cavity, and posterior cortex of the tibia.Recognition of these findings can prevent misdiagnosis and may prove helpful in the planning of appropriate treatment.
View details for DOI 10.1148/radiology.202.3.9051030
View details for PubMedID 9051030
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Epithelioid hemangioendothelioma of bone.
Skeletal radiology
1996; 25 (4): 391-5
Abstract
Neoplasms of bone can arise from any of the cellular elements that constitute osseous tissues. Although tumors of vascular origin are not uncommon, the vast majority are benign. A rare malignant vascular tumor--epithelioid hemangioendothelioma of bone--classifically affects young males and produces osteolytic lesions involving the cortex and cancellous bone of the lower extremities. We present a case with these findings, as well as such unusual findings as cervical spine instability and lesions affecting no fewer than 45 different bones. We conclude that epithelioid hemangioendothelioma should be investigated by skeletal survey because (1) osteolytic lesions involving more that 50% of the cortex present a serious risk for pathologic fracture and (2) the natural history of multicentric epithelioid hemangioendothelioma is more indolent than its solitary counterparts.
View details for DOI 10.1007/s002560050102
View details for PubMedID 8738008
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MR arthrography detects subtle joint pathology.
Diagnostic imaging
1996; 18 (3): 42-4, 47-9
Abstract
In the inevitable cost-benefit analysis to come, the appropriate role of MR arthrography will rightly be challenged. As arthroscopic and MR imaging techniques become even more widespread and refined, a well-defined niche for MR arthrography will eventually emerge.
View details for PubMedID 10184582
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Spiral computed tomography.
The Western journal of medicine
1994; 160 (5): 454-5
View details for PubMedID 8048231
View details for PubMedCentralID PMC1022492
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Metallic foreign bodies in the orbits of patients undergoing MR imaging: prevalence and value of radiography and CT before MR.
AJR. American journal of roentgenology
1994; 162 (4): 981-3
Abstract
The purpose of this study was to measure the prevalence of metallic foreign bodies in the orbits of 15,024 patients who were scheduled for MR imaging during a 4-year period and to determine if screening by plain radiography, CT, or both before MR imaging is efficacious.Records of 15,024 patients scheduled for MR imaging were reviewed. A total of 1593 patients who had identified themselves as being at risk for an intraorbital metallic foreign body had undergone plain radiography or CT of the orbits. Plain radiographs and/or CT scans of patients reported as having orbital metal were reviewed to confirm the presence of a metallic foreign body and to identify its location.Metallic foreign bodies were discovered in 40 patients. Six of these patients had impaired vision in the involved eye. Ten patients had a metallic foreign body in or near the orbit but well away from the globe and were thought to be at low risk for movement of the foreign body as a result of MR imaging. The other 24 patients had metallic foreign bodies adjacent to or within the globe and were thought to be at risk for movement of the metallic foreign body as a result of MR imaging.The prevalence of intraorbital metallic foreign bodies in our study population was low (0.27%). Even in those patients identified as being at risk, the prevalence was only 2.5%. Based on the number of MR examinations performed annually in the United States and on data indicating that no radiographic screening is performed at 5% of institutions, we extrapolate that more than 2400 patients with intraorbital metallic foreign bodies have undergone MR imaging since 1986 without report of injury. These data allow us to infer that the risk of eye damage for patients who have intraorbital metal is low and that radiographic screening before MR imaging is not needed as often as it is done.
View details for DOI 10.2214/ajr.162.4.8141030
View details for PubMedID 8141030
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Injuries associated with MR imaging: survey of safety records and methods used to screen patients for metallic foreign bodies before imaging.
AJR. American journal of roentgenology
1994; 162 (1): 189-94
Abstract
The purpose of this study was to survey the methods used by academic institutions for identifying patients who might have metallic foreign bodies or other contraindications to MR imaging. We also sought to determine the types of MR-related injuries and any subsequent legal action that might have occurred at these institutions.A survey on these issues was mailed to 207 academic institutions listed in the American Medical Association's Directory of Graduate Medical Education Programs. Institutions that did not respond by mail were contacted by phone. The survey requested information on the use of questionnaires, plain radiography, CT, and metal detectors for screening potential MR imaging subjects, as well as on any MR-related injuries and subsequent legal action. Responses were entered into a data base and response percentages were calculated for each question.The overall response rate for the survey was 99% (206/207). These 206 institutions have a total of 368 MR imaging units, with a mean number of 1.8 MR units per department (range, none to nine). Data from a total of 205 different sites revealed that all patients are screened before MR imaging with a written questionnaire at 93% of all institutions (190/205). For selected indications, 85% of departments (174/205) screen with plain film radiography of the orbits. For selected indications, 41% of facilities (83/205) screen with CT of the orbits. Patients are sometimes screened with a metal detector or magnetometer in 12% of the departments (24/205). Ten departments reported serious injuries relating to MR imaging. The most serious injury occurred when an oxygen tank near the magnet became a missile and struck a patient's face. Most injuries (nine of 14) were burns. Two institutions also reported adverse reactions to gadopentetate dimeglumine. Injuries prompted legal action against four of the 10 institutions. No injuries were related to intraorbital foreign bodies, vascular clips, or pacemakers in patients.These data demonstrate the lack of consensus on screening protocols before MR imaging. Accidents are uncommon, but most accidents that do occur are potentially severe and easily preventable. We recommend that all patients be screened by a written questionnaire followed by oral questioning before imaging to determine those who are at risk. Specific questions should investigate the possibility that patients have ferromagnetic foreign bodies or implants anywhere in the body that are electrically, magnetically, or mechanically activated. All facilities must maintain a high state of vigilance in an effort to prevent iatrogenic burns and injuries from ferromagnetic missiles.
View details for DOI 10.2214/ajr.162.1.8273663
View details for PubMedID 8273663
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Magnetic resonance imaging of musculoskeletal tumors.
The Western journal of medicine
1992; 156 (3): 295
Abstract
The Scientific Board of the California Medical Association presents the following inventory of items of progress in radiology. Each item, in the judgment of a panel of knowledgeable physicians, has recently become reasonably firmly established, both as to scientific fact and important clinical significance. The items are presented in simple epitome, and an authoritative reference, both to the item itself and to the subject as a whole, is generally given for those who may be unfamiliar with a particular item. The purpose is to assist busy practitioners, students, researchers, or scholars to stay abreast of these items of progress in radiology that have recently achieved a substantial degree of authoritative acceptance. Whether in their own field of special interest or another. The items of progress listed below were selected by the Advisory Panel to the Section on Radiology of the California Medical Association, and the summaries were prepared under its direction.
View details for PubMedID 1595247
View details for PubMedCentralID PMC1003238