Faculty Bibliography

Episodic care forms a payment methodology of increasing relevance to neurointerventional specialists and other providers. Episodic care payment models are currently recognized in both payment paths described by the Medicare Access and Children's Health Insurance Program (CHIP) Reauthorization Act (MACRA): the Merit-Based Incentive Payment System and Advanced Alternative Payment Models. Understanding the cost of care, as well as how such costs are shaped in the context of episodic care, will be critical to success in both of these paths.

OBJECTIVE: The purpose of this study is to assess informal consultations between radiologists and referring physicians as identified through an electronic medical record (EMR) search. MATERIALS AND METHODS: The EMR was searched for physician notes containing either the term "radiologist" or "radiology" in combination with any of the following: "second opinion," "second-opinion," "2nd opinion," "2nd-opinion," "rereview," "re-review," "reread," "re-read," "overread," "over-read," "spoke with," "discussed with," or "reviewed with." A sample of 300 notes describing a consultation by a referring physician with a diagnostic radiologist was identified. RESULTS: Of the consultations, 73.3% were related to a specific previously interpreted imaging study, and 26.7% were related to other general management issues, including patient safety. Only 18.7% of the physicians' notes indicated the name of the consulted radiologist; a fraction of these consultations were with a radiologist other than the one who originally interpreted the study or with a radiologist at an outside institution. Of consultations with a local radiologist regarding a specific prior examination, 33.9% resulted in a new finding, a change in severity of a previously detected finding, or a change in management recommendation. Of consultations with a change from the initial report, 24.6% were documented by the radiologist via an addendum; 92.9% of these addenda agreed with the referring physicians' notes. CONCLUSION: Radiologists may be unaware of how their consultations are captured within physician notes that may be incomplete or misrepresent the communication. Radiology practices should consider developing policies requiring radiologists to document informal consultations potentially affecting patient management, while developing solutions to facilitate such documentation when it is not readily achieved through report addenda (e.g., through direct documentation by the radiologist in the EMR).

OBJECTIVE:The purpose of this study was to compare image quality and tumor assessment at prostate magnetic resonance imaging (MRI) between reduced field-of-view diffusion-weighted imaging (rFOV-DWI) and standard DWI (st-DWI). METHODS:A total of 49 patients undergoing prostate MRI and MRI/ultrasound fusion-targeted biopsy were included. Examinations included st-DWI (field of view [FOV], 200 × 200 mm) and rFOV-DWI (FOV, 140 × 64 mm) using a 2-dimensional (2D) spatially-selective radiofrequency pulse and parallel transmission. Two readers performed qualitative assessments; a third reader performed quantitative evaluation. RESULTS:Overall image quality, anatomic distortion, visualization of capsule, and visualization of peripheral/transition zone edge were better for rFOV-DWI for reader 1 (P ≤ 0.002), although not for reader 2 (P ≥ 0.567). For both readers, sensitivity, specificity, and accuracy for tumor with a Gleason Score (GS) of 3 + 4 or higher were not different (P ≥ 0.289). Lesion clarity was higher for st-DWI for reader 2 (P = 0.008), although similar for reader 1 (P = 0.409). Diagnostic confidence was not different for either reader (P ≥ 0.052). Tumor-to-benign apparent diffusion coefficient ratio was not different (P = 0.675). CONCLUSIONS:Potentially improved image quality of rFOV-DWI did not yield improved tumor assessment. Continued optimization is warranted.

Systematic transrectal ultrasonography (US)-guided biopsy is the standard approach for histopathologic diagnosis of prostate cancer. However, this technique has multiple limitations because of its inability to accurately visualize and target prostate lesions. Multiparametric magnetic resonance (MR) imaging of the prostate is more reliably able to localize significant prostate cancer. Targeted prostate biopsy by using MR imaging may thus help to reduce false-negative results and improve risk assessment. Several commercial devices are now available for targeted prostate biopsy, including in-gantry MR imaging-targeted biopsy and real-time transrectal US-MR imaging fusion biopsy systems. This article reviews the current status of MR imaging-targeted biopsy platforms, including technical considerations, as well as advantages and challenges of each technique. (c) RSNA, 2017.

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.

PURPOSE: The aim of this study was to assess both existing Medicare provider code assignments and a new claims-based system for subspecialty classification of private practice radiologists. METHODS: Websites of the 100 largest US radiology private practices were used to identify 1,476 radiologists self-identified with a single subspecialty ([1] abdominal, [2] breast, [3] cardiothoracic, or [4] musculoskeletal imaging; [5] nuclear medicine; [6] interventional radiology; [7] neuroradiology). Concordance of existing Medicare radiology subspecialty provider codes (present only for nuclear medicine and interventional radiology) was first assessed. Next, using a classification approach based on Neiman Imaging Types of Service (NITOS) piloted among academic practices, the percentage of subspecialty work relative value units (wRVUs) from 2012 to 2014 Medicare claims were used to assign each radiologist a unique subspecialty. RESULTS: Existing Medicare provider codes matched only 8.0% of nuclear medicine physicians and 10.7% of interventional radiologists to their self-reported subspecialties. The NITOS-based system mapped a median 51.9% of private practice radiologists' wRVUs to self-identified subspecialties (range, 23.3% [nuclear medicine] to 73.6% [neuroradiology]). The 50% NITOS-based wRVU threshold previously established for academic radiologists correctly assigned subspecialties to 48.8% of private practice radiologists but incorrectly categorized 2.9%. Practice patterns of the remaining 48.3% were sufficiently varied such that no single subspecialty assignment was possible. CONCLUSIONS: Existing Medicare provider codes poorly mirror subspecialty radiologists' own practice website-designated subspecialties. Actual payer claims data permit far more granular and accurate subspecialty identification for many radiologists. As new payment models increasingly focus on subspecialty-specific performance measures, claims-based identification methodologies show promise for reproducibly and transparently matching radiologists to practice-relevant metrics.

OBJECTIVE: The objective of our study was to assess the utility of CT features in the diagnosis of cecal volvulus. MATERIALS AND METHODS: Forty-three patients undergoing CT for cecal volvulus and with surgical or clinical follow-up were included. Two radiologists (11 years and 1 year of experience) evaluated CT examinations for the following: whirl sign, abnormal cecal position, "bird beak" sign, severe cecal distention, mesenteric engorgement, a newly described "central appendix" sign (defined as abnormal appendix position near midline), and overall impression for cecal volvulus. Univariable and multivariable assessments were performed. Patients with CT examinations in which the appendix was not visible were excluded from calculations involving the central appendix sign. RESULTS: Fifty-one percent (n = 22) of patients had cecal volvulus. All CT findings were significantly more common in patients with cecal volvulus (p < 0.01) other than mesenteric engorgement for reader 1 (p = 0.332). Readers 1 and 2 identified the central appendix sign in 92.9% and 92.3% of patients with volvulus versus in 37.5 and 31.1% of patients without volvulus. The whirl sign exhibited a sensitivity for cecal volvulus of 90.9% for reader 1 and 95.5% for reader 2, and a specificity of 61.9% for both readers. Abnormal cecal position exhibited a sensitivity of 90.0% for reader 1 and 100.0% for reader 2 and a specificity of 66.7% and 38.1%. The bird beak sign exhibited a sensitivity of 86.4% for reader 1 and 100.0% for reader 2 and a specificity of 85.7% and 71.4%. Severe cecal distention exhibited a sensitivity of 100.0% for both readers and a specificity of 81.0% and 61.9%. Mesenteric engorgement exhibited a sensitivity of 40.9% for reader 1 and 100.0% for reader 2 and a specificity of 76.2% and 71.4%. The central appendix sign exhibited a sensitivity of 92.9% for reader 1 and 92.3% for reader 2 and a specificity of 62.5% and 68.8%. Overall impression exhibited a sensitivity of 100.0% for both readers and a specificity of 76.2% and 57.1%. At multivariable analysis, the AUC for cecal volvulus ranged from 0.787 to 0.931, and the whirl sign was an independent predictor of volvulus for both readers (p