Female and underrepresented minority representation in radiology.

RATIONAL AND OBJECTIVE: Diversity, equity, inclusion, and representation in various sectors have garnered increasing attention in the past two decades, including healthcare. In this report we investigate representation of females and underrepresented minorities (URM) in the field of radiology and asses for significant growth trends in representation in residency training programs in the United States. MATERIALS AND METHODS: De-identified trainee demographic information for active radiology trainees from 2016 to 2021 was queried using the Accreditation Council for Graduate Medical Education (ACGME), and new radiology trainees using the National Resident Matching Program (NRMP)'s Main Residency Match Data and Reports databooks. RESULTS: In 2021 females represented 26.7% of DR residency trainees and 22% of IR integrated trainees. In the same year URM trainees represented 11.3% of trainees and 8.7% of IR integrated trainees. From 2017 to 2021, diagnostic radiology had a compound average growth rate (CAGR) 1% (p <0.01) of female representation and 1.12% (p<0.01) of URM representation. CONCLUSION: This study quantifies female and underrepresented minority representation among radiology trainees for diagnostic radiology and radiology subspecialities, identifying modest uptrends in representation within both demographics.

Tumefactive Nonneoplastic Proliferative Pseudotumors of the Kidneys and Urinary Tract: CT and MRI Findings with Histopathologic Correlation.

A diverse spectrum of pathologically distinct, nonneoplastic, proliferative conditions of the kidneys and urinary tract demonstrate a expansile growth pattern similar to that of neoplasms. The renal pseudotumors include myriad causes of infections as well as rare noninfectious causes such as sarcoidosis, amyloidosis, and immunoglobulin G4-related disease (IgG4-RD). Rare entities such as cystitis cystica, endometriosis, nephrogenic adenoma, and pseudosarcomatous myofibroblastic proliferation and distinct types of prostatitis comprise tumefactive nontumorous disorders that affect specific segments of the urinary tract. The pseudotumors of the kidneys and urinary tract demonstrate characteristic histopathologic and epidemiologic features, as well as protean clinical manifestations, natural history, and imaging findings. Many patients present with genitourinary tract-specific symptoms or systemic disease. Some cases may be incidentally discovered at imaging. Some entities such as perinephric myxoid pseudotumors, IgG4-RD, fibroepithelial polyp, and nephrogenic adenoma display specific anatomic localization and disease distribution. Imaging features of multisystem disorders such as tuberculosis, sarcoidosis, and IgG4-RD provide supportive evidence that may allow precise diagnosis. Fungal pyelonephritis, xanthogranulomatous pyelonephritis, IgG4-RD, actinomycosis, and endometriosis show markedly low signal intensity on T2-weighted MR images. Although some pseudotumors exhibit characteristic imaging findings that permit correct diagnosis, laboratory correlation and histopathologic confirmation are required for definitive characterization in most cases. A high index of suspicion is a prerequisite for diagnosis. Accurate diagnosis is critical for instituting optimal management while preventing use of inappropriate therapies or interventions. Surveillance CT and MRI are frequently used for monitoring the response of pseudotumors to therapy. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

MR elastography, T1 and T2 relaxometry of liver: role in noninvasive assessment of liver function and portal hypertension.

PURPOSE: To evaluate the correlation between liver stiffness as measured on MR elastography and T1 and T2 relaxation times from T1 and T2 mapping with clinical parameters of liver disease, including the MELD score, MELD-Na and ALBI grade, and endoscopically visible esophageal varices. MATERIALS AND METHODS: 223 patients with known or suspected liver disease underwent MRI of the liver with T1 mapping (Look-Locker sequence) and 2D SE-EPI MR elastography (MRE) sequences. 139 of these patients also underwent T2 mapping with radial T2 FS sequence. Two readers measured liver stiffness, T1 relaxation times and T2 relaxation times, and assessed qualitative features such as presence or absence of cirrhosis, ascites, spleen length, and varices on conventional MRI images. A third reader collected the clinical data (MELD score, MELD-Na Score, ALBI grade, and results of endoscopy in 78 patients). RESULTS: Significant moderate correlation was found between MELD score and all three imaging techniques for both readers (MRE, r = 0.35 and 0.28; T1 relaxometry, r = 0.30 and 0.29; T2 relaxometry, r = 0.45, and 0.37 for reader 1 and reader 2 respectively). Correlation with MELD-Na score was even higher (MRE, r = 0.49 and 0.40; T1, r = 0.45 and 0.41; T2, r = 0.47 and 0.35 for reader 1 and reader 2 respectively). Correlations between MRE and ALBI grade was significant and moderate for both readers: r = 0.39 and 0.37, higher than T1 relaxometry (r = 0.22 and 0.20) and T2 relaxometry (r = 0.17, and r = 0.24). Significant moderate correlations were found for both readers between MRE and the presence of varices on endoscopy (r = 0.28 and 0.30). MRE and T1 relaxometry were significant predictors of varices at endoscopy for both readers (MRE AUC 0.923 and 0.873; T1 relaxometry AUC = 0.711 and 0.675 for reader 1 and reader 2 respectively). Cirrhotic morphology (AUC = 0.654), spleen length (AUC = 0.610) and presence of varices in the upper abdomen on MRI (AUC of 0.693 and 0.595) were all significant predictors of endoscopic varices. Multivariable logistic regression model identified that spleen length and liver MRE were significant independent predictors of endoscopic varices for both readers. CONCLUSION: MR elastography, T1 and T2 relaxometry demonstrated moderate positive correlation with the MELD score and MELD-Na Score. Correlation between MRE and ALBI grade was superior to T1 and T2 relaxometry methods. MRE performed better than T1 and T2 relaxometry to predict the presence of varices at endoscopy. On multivariate analyses, spleen length and MRE were the only two significant independent predictors of endoscopic varices.

T1 mapping, T2 mapping and MR elastography of the liver for detection and staging of liver fibrosis.

PURPOSE: To compare liver stiffness measurements obtained from MR elastography with liver T1 relaxation times obtained from T1 mapping and T2 relaxation times obtained from T2 mapping for detection and staging of liver fibrosis. MATERIALS AND METHODS: 223 patients with known or suspected liver disease underwent MRI of the liver with T1 mapping (Look-Locker sequence) and 2D SE-EPI MR elastography (MRE) sequences. 139 of these patients also underwent T2 mapping with radial T2 TSE sequence. Two readers (R1 & R2) measured liver stiffness, T1 relaxation times and T2 relaxation times. T1 and T2 times were correlated with stiffness measurements. ROC analysis was used to compare the performance of both techniques in discriminating fibrosis stage in 23 patients who underwent liver biopsy. RESULTS: For each reader there was significant moderate positive correlation between liver MRE and liver T1 mapping (r = 0.49 and 0.36). There was significant moderate positive correlation between liver T2 mapping and each of MRE and T1 mapping for one of the readers (r = 0.40 and 0.27). AUC for differentiating early (F0-F2) from advanced (F3-F4) fibrosis in biopsied patients was 0.975 (R1) and 0.925 (R2) for MRE, 0.671 (R1) and 0.642 (R2) for T1 mapping and 0.671 (R1) and 0.743 (R2) for T2 mapping. Inter-reader agreement was good for MRE (ICC = 0.84) substantial for T1 mapping (0.94) and T2 mapping (0.96). CONCLUSIONS: Liver T1 and T2 mapping showed moderate positive correlation with MR elastography. Accuracy of MRE is however superior to T1 and T2 mapping in the subset of patients who underwent liver biopsy. Accuracy of combination of MRE and T1 mapping/T2 mapping was not superior to MRE alone.

Endoscopic and surgical treatment options for chronic pancreatitis: an imaging perspective.

Chronic pancreatitis is a chronic fibro-inflammatory syndrome characterized by chronic pancreatic inflammation leading to fibrosis and scarring. Patients with this multifactorial debilitating illness often require endoscopic or surgical intervention for treatment. Radiologists play a crucial role in pre-therapeutic workup as well as post-treatment imaging of chronic pancreatitis. This review summarizes the most common surgical and endoscopic treatment options that are currently available for chronic pancreatitis, including the implications on imaging.

Detection of hepatic steatosis and iron content at 3 Tesla: comparison of two-point Dixon, quantitative multi-echo Dixon, and MR spectroscopy.

PURPOSE: To compare qualitative results obtained from computer-aided dual-ratio analysis on T1-weighted two-point Dixon, with T2*-corrected multi-echo Dixon and T2-corrected multi-echo single-voxel MR spectroscopy sequence (MRS) for evaluation of liver fat and iron at 3T. METHODS AND MATERIALS: This retrospective, HIPAA-compliant, IRB-approved study included 479 patients with known or suspected liver disease. Two-point Dixon, multi-echo Dixon, and MR spectroscopy sequences were performed for each patient at 3T. A receiver-operating characteristic analysis was performed to compare the diagnostic performance in 80 patients using biopsy as the standard. Sensitivity, specificity, PPV, and NPV of qualitative two-point Dixon results, multi-echo Dixon (PDFF and R2*), and MRS (fat fraction and R2 water) for detection of hepatic steatosis and siderosis were assessed. RESULTS: Fat fractions obtained from MRS and multi-echo Dixon have equivalent accuracy for detection of hepatic steatosis (AUC, sensitivity and specificity: 0.90 vs 0.88, 0.77 vs. 0.82, and 0.90 vs. 0.82), but the optimal cutoff value is higher for MRS (6.05% vs. 3.4%). The dual-ratio Dixon discrimination technique showed high negative predictive value for detection of hepatic steatosis and siderosis (0.90 and 0.94, respectively). R2* from multi-echo Dixon and R2water from MRS have equivalent accuracy for detection of iron overload at 3T (AUC 0.89 vs. 0.88). The optimal cutoff for R2* and R2water are 60.5 s-1 and 40.85 s-1, respectively. CONCLUSION: The computer-aided dual-ratio discrimination with two-point Dixon is a useful qualitative screening tool with high negative predictive value for hepatic steatosis and iron overload. Multi-echo Dixon and MRS have similar accuracy for detection of hepatic steatosis and iron overload at 3 Tesla.

MR elastography of liver at 3 Tesla: comparison of gradient-recalled echo (GRE) and spin-echo (SE) echo-planar imaging (EPI) sequences and agreement across stiffness measurements.

PURPOSE: To compare 2D gradient-recalled echo (GRE) and 2D spin-echo (SE) echo-planar imaging (EPI) MR elastography (MRE) for measurement of hepatic stiffness in adult patients with known or suspected liver disease at 3 Tesla. MATERIALS AND METHODS: Three hundred and eighty-seven consecutive patients underwent MRE of the liver at 3 Tesla with 2D-GRE and 2D-SE-EPI sequences. 'Mean liver stiffness (LS)' calculated by averaging 3 ROIs in the right lobe, 'Maximum LS' calculated by an ROI in the right lobe; and 'Freehand LS' calculated by an ROI in the entire liver were measured by two independent readers. Inter-observer and inter-class variability in stiffness measurements were assessed. Stiffness values were correlated with degree of liver fibrosis (METAVIR scores) in 97 patients who underwent biopsy. The diagnostic performance was compared by a receiver-operating characteristic analysis. RESULTS: The technical failure rate was 2.8% for 2D-SE-EPI (11/387) and 4.1% for 2D-GRE (16/387, 9 had R2* > 80 s-1 indicating iron overload). There is high reproducibility for both GRE and SE-EPI variants (ICC = 0.84-0.94 for both GRE and SE-EPI MRE). The highest sensitivity, specificity, and accuracy of differentiating mild fibrosis (F0-F2) from advanced fibrosis (F3-F4) are 0.84 (GRE Freehand measurement), 0.92 (GRE Maximum stiffness measurement), and 0.88 (GRE Freehand measurement), respectively. CONCLUSIONS: High intra-class correlation and intra-reader correlation are seen on measured hepatic stiffness for both 2D-GRE and 2D-SE-EPI MRE. 2D-SE-EPI has lower failure rate. Diagnostic performance of both sequences is equivalent, with highest sensitivity for 2D-GRE Freehand stiffness measurement, and highest specificity 2D-GRE Maximum stiffness measurement.

von Hippel-Lindau Disease: Review of Genetics and Imaging.

von Hippel-Lindau (VHL) disease is an autosomal-dominant, hereditary, multisystem neoplasia syndrome with increased susceptibility to several benign and malignant tumors. VHL occurs in about 1 in 36,000 live births and is associated with germline mutation of the VHL tumor suppressor gene on the short arm of chromosome 3. VHL disease exhibits diverse genotype and phenotype correlations, exhibits variable intrafamilial and interfamilial expressivity, and can manifest with benign and malignant tumors of the central nervous system, kidneys, adrenals, pancreas, and reproductive organs. Imaging and management of this entity are therefore multidisciplinary. An overview of VHL disease is presented.