Faculty Bibliography

Purpose: To demonstrate the appearance of osseous pathologies other than traumatic bone marrow edema using DECT with virtual noncalcium application for bone marrow edema and color overlay in patients presenting acutely to the emergency department with atraumatic musculoskeletal pain. Materials and Methods: This study was IRB approved and informed consent was waived. 166 consecutive patients presenting to the emergency department from 2/1/2017 - 7/1/2017 who underwent DECT (Somatom Force, Siemens) for musculoskeletal indications were retrospectively identified. CTs performed for the indication of trauma (n=113) were excluded. Post-processing was performed offline using a virtual noncalcium algorithm with color overlay (syngo.via; Siemans). Demographics were extracted from the electronic medical record. Descriptive statistics were performed. Results: In the study period, 20 females and 31 males, average age 59 years (range 20-92) underwent 53 CTs. Indications for imaging were infection (n=28), postoperative pain (n=2), and atraumatic pain (n=23). 34 (64%) had only soft tissue findings or were negative. 19 (36%) demonstrated atraumatic osseous etiologies of pain including metastasis, primary bone tumor, osteomyelitis, and inflammatory or infectious arthropathy. The appearance of these etiologies with color overlay is illustrated. 15 (28%) underwent subsequent imaging with MRI, bone scan, or PET with concordant results and these correlates are shown. Conclusion: DECT has emerged as a technology for detecting traumatic bone marrow edema. Bone marrow edema related to other, atraumatic etiologies including inflammatory arthropathy, tumor, and infection are also visually highlighted by this technique. In the emergent setting, DECT with virtual noncalcium subtraction and color overlay may be a useful adjunct to provide a visual aid for the detection or exclusion of marrow edema or amarrow infiltrating process in patients presenting with atraumatic musculoskeletal pain

Purpose: To determine if direct magnetic resonance arthrography (MRA) is more cost-effective than a non-contrast magnetic resonance imaging (MRI) in the management of superior labral anterior to posterior (SLAP) tears. Materials and Methods: Our base case was a 25-year-old with clinical findings of a SLAP tear in whom an imaging test is being ordered for further management. Decision analysis software (Tree Age Pro) was used to create a model from the healthcare perspective to evaluate the cost effectiveness of 4 imaging strategies: 3-Tesla (T) MRA, 3T MRI, 1.5T MRA and 1.5TMRI. Probability and utility estimates were obtained from published literature. Commercial insurance and Medicaid reimbursements were estimated using 2017 Medicare rates. Effectiveness was measured in quality-adjusted life years (QALY) over a 2-year period and costs were calculated in 2017 U.S. dollars. Results: 3T MRI was the least expensive ($5975) and most effective (1.62278 QALY) strategy for our base case and was dominant to 3T MRA ($6569, 1.61732 QALY), 1.5T MRA ($6790, 1.60517 QALY) and 1.5T MRI ($6823, 1.58544 QALY). The results remained robust and did not change over a reasonable range of costs, utilities and probabilities in 1-way sensitivity analyses. 3T MRA only becomes a cost-effective option if the specificity of 3T MRI drops below 91% with a willingness-to-pay (WTP) threshold of $100,000 or below 88.5% with WTP threshold of $50,000. If 3T is excluded from the analysis, 1.5T MRA is dominant for our base case but 1.5T MRI also becomes a cost effective option if its specificity is higher than 68%. Conclusion: 3TMRI is themost cost-effective option for management of SLAP tears. If a 3T magnet is not available, 1.5T MRA is the most cost effective option. In both circumstances, the most cost effective option is the test with highest specificity

Purpose: As glenohumeral osteoarthritis progresses, there is increased risk for posterior glenoid bone loss which impacts an increasingly common treatment for these patients, total shoulder arthroplasty. Defining the level of maximum posterior bone loss and accurate assessment of its severity, using glenoid version measurements, are crucial to correctly align the glenoid prosthesis with glenoid to prevent prosthetic failure. While the importance of this information is clear, how these measurements should be performed remains in question with several techniques described in the literature. The purpose of this study was to define the most accurate level to measure glenoid version on CT for the most clinically relevant variants of posterior glenoid bone loss, Walch B2 and B3 types. Materials and Methods: 386 consecutive CT shoulder studies performed for shoulder arthroplasty preoperative planning between 2013- 2016 were retrospectively reviewed. Patients with B2 and B3 glenoid types were included. Two radiologists measured glenoid retroversion independently according to Friedman method on true axial CT images using the "intermediate glenoid line", at three glenoid heights: 25% (upper) 50% (equator) and 75% (lower). Results: 29 B2 and 8 B3 glenoid types were included. There was no statistically significant difference found in the retroversion measurements performed by each reader at the three glenoid levels on the B2 or B3 glenoid types (Mean angles (%) in upper, equator and lower in B2: 16.5, 17,0 and 17.5 and B3: 20.6, 20.7 and 23.2, respectively). There was substantial inter-reader correlation (r>=0.7) in angle measurements. Conclusion: Our study suggests that glenoid version can be accurately measured at any level between 25%-75%of the glenoid height forWalch B2 and B3 types. We recommend that the glenoid equator be used as the reference in order to assure consistent and reliable version measurements in this group of patients

RATIONALE AND OBJECTIVES: Correlation of imaging studies and reference standard outcomes is a significant challenge in radiology. This study evaluates the effectiveness of a new communication tool by assessing the ability of this system to correctly match the imaging studies to arthroscopy reports and qualitatively assessing radiologist behavior before and after the implementation of this system. MATERIALS AND METHODS: Using a commercially available communication or educational tool and applying a novel matching rule algorithm, radiology and arthroscopy reports were matched from January 17, 2017 to March 1, 2017 based on anatomy. The interpreting radiologist was presented with email notifications containing the impression of the imaging report and the entire arthroscopy report. Total correlation rate of appropriate report pairings, modality-specific correlation rate, and the anatomy-specific correlation rate were calculated. Radiologists using the system were given a survey. RESULTS: Overall correlation rate for all musculoskeletal imaging was 83.1% (433 or 508). Low correlation was found in fluoroscopic procedures at 74.4%, and the highest correlation was found with ultrasound at 88.4%. Anatomic location varied from 51.6% for spine to 98.8% for hips and pelvis studies. Survey results revealed 87.5% of the respondents reporting being either satisfied or very satisfied with the new communication tool. The survey also revealed that some radiologists reviewed more cases than before. CONCLUSIONS: Matching of radiology and arthroscopy reports by anatomy allows for excellent report correlation (83.1%). Automated correlation improves the quality and efficiency of feedback to radiologists, providing important opportunities for learning and improved accuracy.

RATIONALE AND OBJECTIVES: Here we review the current state of multicenter radiology research (MRR), and utilize a survey of experienced researchers to identify common advantages, barriers, and resources to guide future investigators. MATERIALS AND METHODS: The Association of University Radiologists established a Radiology Research Alliance task force, Multi-center Research Studies in Radiology, composed of 12 society members to review MRR. A REDCap survey was designed to gain more insight from experienced researchers. Recipients were authors identified from a PubMed database search, utilizing search terms "multicenter" or "multisite" and "radiology." The survey included investigator background information, reasons why, barriers to, and resources that investigators found helpful in conducting or participating in MRR. RESULTS: The survey was completed by 23 of 80 recipients (29%), the majority (76%) of whom served as a primary investigator on at least one MRR project. Respondents reported meeting collaborators at national or international (74%) and society (39%) meetings. The most common perceived advantages of MRR were increased sample size (100%) and improved generalizability (91%). External funding was considered the most significant barrier to MRR, reported by 26% of respondents. Institutional funding, setting up a central picture archiving and communication system, and setting up a central database were considered a significant barrier by 30%, 22%, and 22% of respondents, respectively. Resources for overcoming barriers included motivated staff (74%), strong leadership (70%), regular conference calls (57%), and at least one face-to-face meeting (57%). CONCLUSIONS: Barriers to MRR include funding and establishing a central database and a picture archiving and communication system. Upon embarking on an MRR project, forming a motivated team who meets and speaks regularly is essential.

PURPOSE: To compare diagnostic performance of a 5-min knee MRI protocol to that of a standard knee MRI. MATERIALS AND METHODS: One hundred 3 T (100 patients, mean 38.8 years) and 50 1.5 T (46 patients, mean 46.4 years) MRIs, consisting of 5 fast, 2D multi-planar fast-spin-echo (FSE) sequences and five standard multiplanar FSE sequences, from two academic centers (1/2015-1/2016), were retrospectively reviewed by four musculoskeletal radiologists. Agreement between fast and standard (interprotocol agreement) and between standard (intraprotocol agreement) readings for meniscal, ligamentous, chondral, and bone pathology was compared for interchangeability. Frequency of major findings, sensitivity, and specificity was also tested for each protocol. RESULTS: Interprotocol agreement using fast MRI was similar to intraprotocol agreement with standard MRI (83.0-99.5%), with no excess disagreement (/= 0.215), except more ACL tears on fast MRI (p = 0.021) and more cartilage defects on standard MRI (p < 0.001). Sensitivities (59-100%) and specificities (73-99%) of fast and standard MRI were not significantly different for meniscal and ligament tears (95% CI for difference, -0.08-0.08). For cartilage defects, fast MRI was slightly less sensitive (95% CI for difference, -0.125 to -0.01) but slightly more specific (95% CI for difference, 0.01-0.5) than standard MRI. CONCLUSION: A fast 5-min MRI protocol is interchangeable with and has similar accuracy to a standard knee MRI for evaluating internal derangement of the knee.

BACKGROUND: The purpose of this study was to determine the value of magnetic resonance imaging (MRI) and ultrasound-based imaging strategies in the evaluation of a hypothetical population with a symptomatic full-thickness supraspinatus tendon (FTST) tear using formal cost-effectiveness analysis. METHODS: A decision analytic model from the health care system perspective for 60-year-old patients with symptoms secondary to a suspected FTST tear was used to evaluate the incremental cost-effectiveness of 3 imaging strategies during a 2-year time horizon: MRI, ultrasound, and ultrasound followed by MRI. Comprehensive literature search and expert opinion provided data on cost, probability, and quality of life estimates. The primary effectiveness outcome was quality-adjusted life-years (QALYs) through 2 years, with a willingness-to-pay threshold set to $100,000/QALY gained (2016 U.S. dollars). Costs and health benefits were discounted at 3%. RESULTS: Ultrasound was the least costly strategy ($1385). MRI was the most effective (1.332 QALYs). Ultrasound was the most cost-effective strategy but was not dominant. The incremental cost-effectiveness ratio for MRI was $22,756/QALY gained, below the willingness-to-pay threshold. Two-way sensitivity analysis demonstrated that MRI was favored over the other imaging strategies over a wide range of reasonable costs. In probabilistic sensitivity analysis, MRI was the preferred imaging strategy in 78% of the simulations. CONCLUSION: MRI and ultrasound represent cost-effective imaging options for evaluation of the patient thought to have a symptomatic FTST tear. The results indicate that MRI is the preferred strategy based on cost-effectiveness criteria, although the decision between MRI and ultrasound for an imaging center is likely to be dependent on additional factors, such as available resources and workflow.

OBJECTIVE: The objective of our study was to assess temporal changes in the utilization of musculoskeletal extremity imaging in Medicare beneficiaries over a recent 20-year period (1994-2013). MATERIALS AND METHODS: Medicare Physician Supplier Procedure Summary Master Files from 1994 through 2013 were used to study changing utilization and utilization rates of the four most common musculoskeletal imaging modalities: radiography, MRI, CT, and ultrasound. RESULTS: Utilization rates (per 1000 beneficiaries) for all four musculoskeletal extremity imaging modalities increased over time: 43% (from 441.7 to 633.6) for radiography, 615% (5.4-38.6) for MRI, 758% (1.2-10.3) for CT, and 500% (1.8-10.8) for ultrasound. Radiologists were the most common billing specialty group for all modalities throughout the 20-year period, maintaining dominant market shares for MRI and CT (84% and 96% in 2013). In recent years, the second most common billing group was orthopedic surgery for radiography, MRI, and CT and podiatry for ultrasound. The physician office was the most common site of service for radiography, MRI, and ultrasound, whereas the hospital outpatient and inpatient settings were the most common sites for CT. CONCLUSION: In the Medicare population, the most common musculoskeletal extremity imaging modalities increased substantially in utilization over the 2-decade period from 1994 through 2013. Throughout that time, radiology remained the most common billing specialty, and the physician office and hospital outpatient settings remained the most common sites of service. These insights may have implications for radiology practice leaders in making decisions regarding capital infrastructure, workforce, and training investments to ensure the provision of optimal imaging services for extremity musculoskeletal care.

OBJECTIVE: This article reviews the normal anatomy of the extensor tendons of the wrist as well as the clinical presentation and MRI appearances of common tendon abnormalities, such as tears, tenosynovitis, intersection syndromes, and associated or predisposing osseous findings. Treatment options are also discussed. CONCLUSION: We review the anatomy and normal MRI appearance of the clinically important dorsal extensor tendons of the wrist, in addition to the spectrum of abnormalities associated with these tendons.

Purpose To evaluate the diagnostic accuracies of nonenhanced magnetic resonance (MR) imaging and MR arthrography for diagnosis of superior labrum anterior-to-posterior (SLAP) tears by using a systematic review and meta-analysis. Materials and Methods A comprehensive literature search was performed on the two main concepts of MR imaging (MR imaging, and direct and indirect MR arthrography) and SLAP tears. Inclusion criteria consisted of original studies that assessed the diagnostic accuracy of MR imaging, direct MR arthrography, and/or indirect MR arthrography for the detection of SLAP tears, by using surgical findings as the reference standard. The Quality Assessment of Diagnostic Accuracy Studies 2, or QUADAS-2 Quality Assessment of Diagnostic Accuracy Studies 2 Quality Assessment of Diagnostic Accuracy Studies 2 , tool was used to assess methodologic quality. Meta-analyses were performed that compared MR imaging studies to direct MR arthrography studies and indirect MR arthrography studies, 3-T studies to 1.5-T studies, and low-bias MR imaging studies to low-bias direct MR arthrography studies. Study variation was analyzed by using the Cochran Q test of heterogeneity and the I2 statistic. Results Thirty-two studies met inclusion and exclusion criteria, including 3524 imaging examinations: 1963 direct MR arthrography examinations (23 studies), 1402 MR examinations (14 studies), and 159 indirect MR arthrography examinations (three studies). Twelve studies had low risk for bias, two had questionable risk, and 18 had high risk. Mean sensitivities of direct MR arthrography, MR imaging, and indirect MR arthrography for SLAP tear diagnosis were 80.4%, 63.0%, and 74.2%, respectively. Mean specificities of direct MR arthrography, MR imaging, and indirect MR arthrography were 90.7%, 87.2%, and 66.5%, respectively. Summary receiver operator characteristic (ROC) curve demonstrated superior accuracy of direct MR arthrography compared with those of MR imaging and indirect MR arthrography. Similar findings were observed in the low-bias subanalysis. Summary ROC curve demonstrated overall superiority of 3-T imaging, with or without intra-articular contrast material compared with 1.5-T imaging, with or without intra-articular contrast material. Significant variance was observed for MR imaging and direct MR arthrography (P < .001) studies for both mean sensitivity and specificity. Conclusion Direct MR arthrography appears to be more accurate than nonenhanced MR imaging for diagnosis of SLAP tears, whereas 3-T MR imaging with or without intra-articular contrast material appears to improve diagnostic accuracy compared with 1.5-T MR imaging with or without intra-articular contrast material. (c) RSNA, 2017 Online supplemental material is available for this article.