Faculty Bibliography

RATIONALE AND OBJECTIVES/OBJECTIVE:Radiology residency often fails to account for individual differences between residents or provide sufficient exposure to diverse pathologies. We sought to evaluate whether artificial intelligence (AI)-enabled "Precision Education" can accurately identify and address individual radiology resident pathology exposure gaps through supplemental personalized teaching cases. MATERIALS AND METHODS/METHODS:A curriculum outlined types and frequencies of important pathologies (IPs) residents should encounter during postgraduate years 2 through 4 (PGY-2 through PGY-4). Daily resident "live" clinical reports were analyzed by ChatGPT-4o prompts to detect IPs encountered. Each resident's live cases were then supplemented with curated anonymized teaching cases, with priority given to IPs encountered below curriculum-defined target thresholds to date. Volumes and IP exposure were compared between pre- (2022-2023) and postintervention (2024-2025) academic years. RESULTS:ChatGPT-4o demonstrated over 91% precision and recall in accurately identifying IPs. Unique IPs encountered by residents significantly increased postintervention from median 75-107 to 93.5-144 in abdominal, 43.5-70 to 73-99 in musculoskeletal, 32.5-38 to 64.5-79 in neuro-, 39.5-49 to 82-96.5 in pediatric, and 42.5-56 to 49.3-85.3 in thoracic imaging (all p < 0.05). Residents met significantly more curriculum-defined targets postintervention, increasing from a median 54-64 to 78.5-131.5 in abdominal, 21-49 to 51.5-75.5 in musculoskeletal, 3.5-9 to 21-38 in neuro-, 13.5-21 to 51.5-72 in pediatric, and 12.5-33 to 23-58 in thoracic imaging (all p < 0.05). Median live case interpretations were not significantly reduced by the intervention, aside from PGY-3 abdominal imaging cases (p = 0.0489). CONCLUSION/CONCLUSIONS:Personalized AI-enabled Precision Education accurately identified resident pathology exposure gaps, enhanced exposure to IPs, and maintained clinical training opportunities.

OBJECTIVE:To retrospectively evaluate the diagnostic utility of dual-energy computed tomography (DECT) virtual non-calcium bone marrow edema (BME) maps in the assessment of osseous pelvic trauma compared to conventional CT. In addition to fracture detection rates, we sought to determine the DECT effect on reader diagnostic confidence and follow-up recommendations. MATERIALS AND METHODS/METHODS:Three radiologists performed independent retrospective reviews of 92 consecutive pelvic CTs for the presence of fractures, without the use of DECT-generated BME maps. Following a washout period of ≥ 4 weeks, the cases were re-reviewed with the addition of DECT BME maps. Comparison of fracture detection rates, frequency of "indeterminate" reads, reader confidence ratings, and follow-up imaging recommendations were performed using McNemar's test and mixed-effects logistic regressions. Mixed-effect models were utilized to assess the effect of DEXA-derived patient bone mineral density, when available, on fracture detection rates. RESULTS:The use of DECT BME maps resulted in higher pooled reader diagnostic confidence, with a mean 0.19 increase on a 5-point Likert scale (p < 0.001). There was, however, no statistically significant difference in fracture detection rates for readers utilizing DECT versus conventional CT alone, with similar rates of "indeterminate" interpretations between the groups. For patients with recent DEXAs (n = 27), DECT was not associated with change in fracture detection rates among patients with osteoporosis or osteopenia. Readers recommended follow-up imaging more frequently in cases interpreted with DECT, but this effect was not significant (p = 0.266). CONCLUSION/CONCLUSIONS:When interpreting pelvic CT for trauma, DECT-generated BME maps increased diagnostic confidence without changing detection rates.

OBJECTIVES/OBJECTIVE:Metal artifact reduction MRI can exceed specific absorption rate (SAR) limits due to high-bandwidth radiofrequency pulses, causing scan interruptions and prolonged acquisition times. The aim of the current study is to reduce SAR and potentially scan time in metal artifact reduction MRI using an optimized variable refocusing flip angle (VRFA) scheme compared with the standard constant refocusing flip angle (CRFA). MATERIALS AND METHODS/METHODS:Three VRFA variants (VRFA1 to VRFA3) were developed to maximize tissue signal and contrast while minimizing SAR and image blur. The optimal variant was selected through quantification of metal artifacts and image blur in phantoms and tissue signal in a volunteer. Patients with hip arthroplasty underwent CRFA and optimal VRFA imaging using high-bandwidth turbo-spin-echo (HBW-TSE) and compressed-sensing slice-encoding-for-metal-artifact-correction (CS-SEMAC) sequences. Three readers ranked paired CRFA and VRFA scans for quality. Analyses included repeated measures ANOVA, noninferiority testing, and paired t/Wilcoxon signed-rank tests. RESULTS:CRFA and VRFA1 to VRFA3 showed no significant differences in image blur (full-width-at-half-maximum, mean ± SD, 1.9 ± 0.2 vs 1.9 ± 0.2 vs 1.9 ± 0.3 vs 1.9 ± 0.3 pixels, P = 0.06) or metal artifacts (8.2 ± 2.8 vs 8.4 ± 2.7 vs 8.4 ± 2.6 vs 8.4 ± 2.7 pixels, P = 0.57). The optimal VRFA variant (VRFA3) preserved 81% of CRFA fat-muscle contrast at 77% SAR and 70% scan time on proton-density (PD), and 94% of fluid-muscle contrast at 80% SAR and 67% scan time on short-tau-inversion-recovery (STIR). In 23 patients [mean age, 67.3 y ± 12.2 (SD); 14 females], the optimal VRFA was noninferior to CRFA in all quality metrics (all 95% CI < noninferiority margin = 0.1) and significantly reduced SAR (mean, PD-HBW-TSE/STIR-HBW-TSE/PD-CS-SEMAC/STIR-CS-SEMAC: 1.11/1.35/1.17/1.18 vs 1.85/1.83/1.49/1.46 W/kg, all P ≤ 0.001). In HBW-TSE, reduced SAR allowed longer echo trains and 15% to 32% shorter scan times. CONCLUSION/CONCLUSIONS:Metal artifact reduction MRI with VRFA reduces SAR without compromising image quality. It allows shorter acquisitions in HBW-TSE.

BackgroundRapid real-time magnetic resonance (MR) sequences enable dynamic articular kinematic assessment. The abduction-external rotation (ABER) position has long been used to characterize glenohumeral pathology.PurposeTo evaluate a dynamic gradient recall echo (GRE) sequence for ABER-positioned glenohumeral joint kinematic assessment correlating with subjective instability and clinical apprehension testing.Material and MethodsSymptomatic patients were scanned using a routine MR arthrogram protocol supplemented by an additional "dynamic ABER" GRE technique acquired with the arm abducted and then internally-externally rotated in real time. Dynamic motion of the humeral head between the extremes of motion in the abducted and externally rotated positions was evaluated. The cohort was followed for 3 years.ResultsA total of 15 dynamic ABER studies in 15 different patients were evaluated by three readers (right: n=9; left: n=6), with a mean age of 30 years (range=19-45 years). Good accuracy of the humeral head excursion between the abducted and externally-internally rotated positions (AUC=0.88) was observed as a test for positively detecting instability. An association was detected between clinical instability and mean humeral head excursion as measured by all three readers (P = 0.026), although no association between positive apprehension testing and mean humeral head excursion was detected. There was a trend towards surgery-naïve patients with higher mean humeral head excursion subsequently undergoing surgical management (P=0.088), although this did not reach statistical significance.ConclusionCorrelation between subjective instability and humeral head translation demonstrated on a dynamic ABER sequence added to MR shoulder arthrograms was observed but without association with clinical apprehension testing.

Ultrasound (US) is a valuable tool in the evaluation of arthritis both for diagnosis and treatment response. Pertinent findings such as joint effusions, synovitis, bursitis, bone erosions, tenosynovitis, and enthesitis can all be readily evaluated sonographically. In this article, we describe specific considerations in the US evaluation of rheumatoid arthritis, psoriatic arthritis, juvenile idiopathic arthritis, crystalline arthritis (gout, calcium pyrophosphate deposition disease, and hydroxyapatite deposition disease), septic arthritis, and osteoarthritis with attention to certain differentiating features. The potential role of US in the diagnosis of specific arthritides is discussed, together with an overview of newer technologies and future directions.

Rheumatoid arthritis is a common chronic inflammatory arthritis, primarily characterized by proliferative synovitis of the small joints of the appendicular skeleton. Rapidly evolving treatment regimens for rheumatoid arthritis patients, including conventional and biologic disease-modifying antirheumatic drugs, promise improved quality of life and prognosis. These treatments necessitate earlier clinical detection of rheumatoid arthritis, a goal that has forever changed the role of imaging in this pursuit. This review discusses the dominant imaging modalities in state-of-the-art rheumatoid arthritis management: radiography, magnetic resonance imaging, and ultrasound. It focuses on hand and wrist evaluation, with key relevant findings detected by each modality and recent evidence supporting them. Emerging techniques are also described in this discussion to understand likely future radiologic contributions to rheumatoid arthritis diagnosis and management.

OBJECTIVE:To evaluate the Neuropathy Score-Reporting and Data System (NS-RADS) MRI grading system in conjunction with electrodiagnostic (EDx) testing for radial neuropathy at the elbow. MATERIALS AND METHODS/METHODS:Patients presenting between 2010 and 2023 with suspected radial neuropathy who underwent both EDx testing in the form of electromyography and nerve conduction studies and MRI within a 12-month period were evaluated. Three blinded radiologists used the NS-RADS grading system to evaluate nerve entrapment (E grades), muscle denervation (M grades) proximally within the supinator/extensor carpi radialis brevis (ECRB), and more distally within the forearm extensor muscles. These grades and the presence of lateral epicondylitis were then correlated with EDx abnormalities. RESULTS:Forty-nine participants were included. Inter-reader reliability for M grades in the forearm extensor muscles was good (ICC = 0.90 [95% CI = 0.83 - 0.94], p < 0.001), as was reliability for the supinator/ECRB muscles (ICC = 0.91 [95% CI = 0.86-0.95], p < 0.001). Inter-reader reliability for E grades was moderate (ICC = 0.83 [95% CI = 0.69-0.90], p < 0.001). Patients with positive EDx studies had a significantly different distribution of M grades for the forearm extensors and supinator/ECRB than those with negative studies (all p values < 0.001). However, overall consensus reads showed no significant difference in the distribution of E grades between patients with positive and negative EDx studies. CONCLUSION/CONCLUSIONS:Muscle grading strongly correlated with EDx positivity, with a high level of inter-reader agreement for muscle denervation-related alterations. Nerve grading, however, did not show a statistical correlation.

Background Conventional chemical shift selective (CHESS) fat suppression may fail in distal extremity MRI due to sensitivity to field inhomogeneities. Purpose To develop a patient-specific fat-suppression method for distal extremity 3-T MRI by exploiting the spectral heterogeneity adaptive radiofrequency pulse (SHARP) technique and to compare it to fat suppression with CHESS. Materials and Methods SHARP uses the routinely acquired frequency spectrum at MRI calibration to adapt the frequency range and time-bandwidth product of the fat-suppression pulse. In this prospective study, fat suppression by SHARP was assessed by numerical simulations, phantom experiments, and imaging in 15 asymptomatic participants who underwent ankle, foot, and hand (in superman and hand-by-the-side positions) MRI using SHARP, CHESS, and reference standard (short-tau inversion recovery or Dixon) techniques. Three readers ranked the MRI scans from 1 (best) to 3 (worst) regarding fat-suppression homogeneity. The added value of SHARP was defined as the difference between the proportions of images where SHARP outranked CHESS and where CHESS outranked SHARP. Friedman, Wilcoxon signed rank, and χ² tests were used to compare in vivo data. Results At numerical simulations, SHARP showed 0% water and 62%-70% fat suppression, whereas CHESS showed 2% water and 57% fat suppression. Phantom data demonstrated lower fat-suppression inhomogeneity indexes with Dixon (1.0%) and SHARP (2.4%) compared with CHESS (10.7%). In 15 participants (mean age, 38.5 years ± 12.8 [SD]; six female participants), mean ranking by readers of fat homogeneity in the reference technique (ankle, foot, hand in superman position, and hand-by-the-side position: 1.02, 1.02, 1.03, and 1.06, respectively) was higher than those with SHARP (1.39, 1.46, 1.50, and 1.66, respectively), which were higher than those with CHESS (1.64, 1.80, 1.61, and 1.80, respectively) (all P < .001). The added value of SHARP was highest for images in the foot (389 of 1158; 33.6%; P < .001 vs other joints), followed by the ankle (247 of 971 [25%]; P < .001 vs both hand positions), and lowest for hand-by-the-side and hand in superman positions (158 of 1223; [13%] and 133 of 1193 [11%], respectively; P = .18). Conclusion SHARP provided more homogeneous fat suppression than CHESS. © RSNA, 2024 Supplemental material is available for this article.