Publications

Gastrointestinal (GI) bleeding is a common potentially life-threatening medical condition frequently requiring multidisciplinary collaboration to reach the proper diagnosis and guide management. GI bleeding can be overt (eg, visible hemorrhage such as hematemesis, hematochezia, or melena) or occult (eg, positive fecal occult blood test or iron deficiency anemia). Upper GI bleeding, which originates proximal to the ligament of Treitz, is more common than lower GI bleeding, which arises distal to the ligament of Treitz. Small bowel bleeding accounts for 5-10% of GI bleeding cases commonly manifesting as obscure GI bleeding, where the source remains unknown after complete GI tract endoscopic and imaging evaluation. CT can aid in identifying the location and cause of bleeding and is an important complementary tool to endoscopy, nuclear medicine, and angiography in evaluating patients with GI bleeding. For radiologists, interpreting CT scans in patients with GI bleeding can be challenging owing to the large number of images and the diverse potential causes of bleeding. The purpose of this pictorial review by the Society of Abdominal Radiology GI Bleeding Disease-Focused Panel is to provide a practical resource for radiologists interpreting GI bleeding CT studies that reviews the proper GI bleeding terminology, the most common causes of GI bleeding, key patient history and risk factors, the optimal CT imaging technique, and guidelines for case interpretation and illustrates many common causes of GI bleeding. A CT reporting template is included to help generate radiology reports that can add value to patient care. An invited commentary by Al Hawary is available online. Online supplemental material is available for this article. ©RSNA, 2021.

Hepatocellular carcinoma (HCC) is a malignancy with variable biologic aggressiveness based on the tumor grade, presence or absence of vascular invasion, and pathologic and molecular classification. Knowledge and understanding of the prognostic implications of different pathologic and molecular phenotypes of HCC are emerging, with therapeutics that promise to provide improved outcomes in what otherwise remains a lethal cancer. Imaging has a central role in diagnosis of HCC. However, to date, the imaging algorithms do not incorporate prognostic features or subclassification of HCC according to its biologic aggressiveness. Emerging data suggest that some imaging features and further radiologic, pathologic, or radiologic-molecular phenotypes may allow prediction of the prognosis of patients with HCC. An invited commentary by Bashir is available online. Online supplemental material is available for this article. ©RSNA, 2021.

CONTEXT.—: Dynamic, contrast-enhanced magnetic resonance imaging (MRI) is a highly sensitive imaging modality used for screening and diagnostic purposes. Nonmass enhancement (NME) is commonly seen on MRI of the breast. However, the pathologic correlates of NME have not been extensively explored. Consequently, concordance between MRI and pathologic findings in such cases may be uncertain and this uncertainty may cause the need for additional procedures.

OBJECTIVE.—: To examine the histologic alterations that correspond to NME on MRI.

DESIGN.—: We performed a retrospective search for women who underwent breast MRI between March 2014 and December 2016 and identified 130 NME lesions resulting in biopsy. The MRI findings and pathology slides for all cases were reviewed. The follow-up findings on any subsequent excisions were also noted.

RESULTS.—: Among the 130 cases, the core needle biopsy showed 1 or more benign lesions without atypia in 80 cases (62%), atypical lesions in 21 (16%), ductal carcinoma in situ in 22 (17%), and invasive carcinoma in 7 (5%). Review of the imaging features demonstrated some statistically significant differences in lesions that corresponded to malignant lesions as compared with benign alterations, including homogeneous or clumped internal enhancement, type 3 kinetics, and T2 dark signal; however, there was considerable overlap of features between benign and malignant lesions overall. Of 130 cases, 54 (41.5%) underwent subsequent excision with only 6 cases showing a worse lesion on excision.

CONCLUSIONS.—: This study illustrates that NME can be associated with benign, atypical, and/or malignant pathology and biopsy remains indicated given the overlap of radiologic features.

PURPOSE: The purpose of the study is to determine if a combination of dermal thickening and subcutaneous fluid honeycombing on non-contrast MRI, termed the dermal rim sign (DRS), can be diagnostically analogous to dermal backflow seen on lymphoscintigraphy in patients with secondary upper extremity lymphedema.

MATERIALS AND METHODS: Upper extremity MRI and lymphoscintigraphy were performed on patients referred to a multidisciplinary lymphedema clinic for suspicion of secondary lymphedema. Sensitivity, specificity, and positive and negative predictive values of DRS on MRI in detecting dermal backflow on lymphoscintigraphy and the correlation between DRS, Indocyanine Green (ICG) lymphography, bioimpedence L-Dex® ratio and MRI Lymphedema Staging were calculated. Weighted interobserver agreements on the presence and location of DRS on MRI were calculated.

RESULTS: Of the 45 patients in the study, 91.1% (41/45) of patients had history of breast cancer. The average age was 58.4 ± 10.5 years, with a mean symptom duration of 4.7 ± 4.4 years. The mean BMI was 30.5 ± 7.0 kg/m2. Interobserver agreement on the presence and the extent of DRS on MRI was 0.93 [95% confidence-interval: 0.80-1]. DRS was present in 97% (32/33) of patients who demonstrated dermal backflow on lymphoscintigraphy. Sensitivity, specificity, PPV, and NPV of DRS were 96.6% [81.7%-99.9%], and 75.0% [47.6%-92.7%], 87.5% [74.9%-94.3%], and 92.3% [63.1%-98.8%]. DRS was associated with severity on ICG lymphography and bioimpedance (both p < 0.001).

CONCLUSIONS: DRS on non-contrast MRI is highly predictive of dermal backflow and correlates with clinical measures of lymphedema severity. DRS may be used as an independent diagnostic biomarker to identify patients who would benefit from dedicated exams.

Liver lesions have different enhancement patterns at dynamic contrast-enhanced imaging. The Liver Imaging Reporting and Data System (LI-RADS) applies the enhancement kinetic of liver observations in its algorithms for imaging-based diagnosis of hepatocellular carcinoma (HCC) in at-risk populations. Therefore, careful analysis of the spatial and temporal features of these enhancement patterns is necessary to increase the accuracy of liver mass characterization. The authors focus on enhancement patterns that are found at or around the margins of liver observations-many of which are recognized and defined by LI-RADS, such as targetoid appearance, rim arterial phase hyperenhancement, peripheral washout, peripheral discontinuous nodular enhancement, enhancing capsule appearance, nonenhancing capsule appearance, corona enhancement, and periobservational arterioportal shunts-as well as peripheral and periobservational enhancement in the setting of posttreatment changes. Many of these are considered major or ancillary features of HCC, ancillary features of malignancy in general, features of non-HCC malignancy, features associated with benign entities, or features related to treatment response. Distinction between these different patterns of enhancement can help with achieving a more specific diagnosis of HCC and better assessment of response to local-regional therapy. ©RSNA, 2021.

PURPOSE: NonHispanic Black (NHB) and Hispanic/Afro-Caribbean men have the highest risk of prostate cancer (PCa) compared to nonHispanic White (NHW) men. However, ethnicity-specific outcomes of targeted fusion biopsy (FB) for the detection of PCa are poorly characterized. We compared the outcomes of FB by Prostate Imaging Reporting and Data System (PI-RADS®) score and race/ethnicity among a diverse population.

MATERIALS AND METHODS: We evaluated all men who underwent image-guided FB for suspicious lesions on prostate magnetic resonance imaging (≥PI-RADS 3) over a 2-year period. We examined associations of race/ethnicity and PI-RADS score with risk of PCa or clinically significant PCa (cs-PCa, Gleason Group ≥2) on FB using mixed-effects logistic regression models.

RESULTS: A total of 410 men with 658 lesions were analyzed, with 201 (49.0%) identified as NHB and 125 (30.5%) identified as Hispanic. NHB men had a twofold increase in the odds of detecting cs-PCa (OR=2.7, p=0.045), while Hispanic men had similar odds of detecting cs-PCa compared to NHW men. With regard to all PCa, NHB men had a similar increase in the odds of detecting all PCa (OR=2.4, p=0.050), which was borderline statistically significant compared to NHW men on FB. When we excluded men on active surveillance, NHB men had even stronger associations with detection of cs-PCa (OR=3.10, p=0.047) or all PCa (OR=2.77, p=0.032) compared to NHW men.

CONCLUSIONS: NHB men have higher odds for overall PCa and cs-PCa on FB compared to NHW men. Further work may clarify differences per PI-RADS score. Clinicians should interpret prostate magnetic resonance imaging lesions with more caution in NHB men.

The global pandemic of coronavirus disease 2019 (COVID-19) has revealed a surprising number of extra-pulmonary manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. While myalgia is a common clinical feature of COVID-19, other musculoskeletal manifestations of COVID-19 were infrequently described early during the pandemic. There have been emerging reports, however, of an array of neuromuscular and rheumatologic complications related to COVID-19 infection and disease course including myositis, neuropathy, arthropathy, and soft tissue abnormalities. Multimodality imaging supports diagnosis and evaluation of musculoskeletal disorders in COVID-19 patients. This article aims to provide a first comprehensive summary of musculoskeletal manifestations of COVID-19 with review of imaging.

Interventional radiology continues to evolve into a more robust and clinically dynamic specialty underpinned by significant advancements in training, education, and practice. This article, prepared by members of the 2020-2021 Association of University Radiologists' task force of the Radiology Research Alliance, will review these developments, highlighting the evolution of interventional radiology pathways with attention to growing educational differences, interrelation to diagnostic radiology training, post-training practice patterns, distribution of procedures and future trends, amongst other key features important to those pursuing a career in interventional radiology as well as those in practice.