Bookwalter, Candice A.

Renovascular hypertension is the most common cause of secondary hypertension, and radiologist awareness of the various imaging appearances and various causes is crucial for accurate diagnosis and guiding treatment.

Abstract Background: Rectosigmoid endometriosis (RSE) presents with a diverse array of MRI findings that impact surgical planning. No standardized reporting and data system has been established for RSE. Purpose: We propose a novel MRI scoring system designed to predict the likelihood of muscularis propria (MP) involvement in RSE, which would, in turn, influence surgical planning. Material and Methods: The records of patients with bowel endometriosis treated surgically from May 2018 to June 2022 were retrieved. Surgery was classified as partial thickness discoid, full thickness discoid, or segmental resection. Each pre-treatment MRI was scored based on the mutual agreement of two abdominal radiologists (reference score). The MRI score was defined as (1) score 0: no evidence of RSE, (2) score 1: minimal tethering involving the serosal surface without MP involvement, (3) score 2: intermediate soft tissue thickening involving the rectosigmoid colon with indeterminate MP involvement, or (4) score 3: definite mushroom cap sign or definite MP involvement. In the reader study, two radiologists independently scored each exam. The area under the curve (AUC) was evaluated for predicting the need for segmental or full thickness discoid resection. Results: The cohort consisted of 95 patients (median age: 36 years); 16, 14, 30, and 35 patients had MRI score 0, 1, 2, and 3, respectively. Patients with MRI scores 3 and 2 underwent partial thickness discoid (6% vs 50%), full thickness discoid (6% vs 17%), and segmental resection (89% vs 33%), respectively. All patients with MRI scores 1 or 0 either underwent partial thickness discoid resection or did not undergo rectosigmoid surgery. The AUCs were 92.2%, 84.5% and 93.9% for MRI scores of the reference, reader 1, and 2, respectively. Conclusion: Our MRI scoring system based on suspected depth of bowel invasion showed good diagnostic performance to predict the type of surgical intervention needed. Summary Statement This novel MRI scoring system for rectosigmoid endometriosis is a concise and qualitative scale based on suspected depth of bowel wall invasion to best guide operative planning.

Objective: To evaluate the effect of hepatic steatosis on LI-RADS® major features at MRI in patients with non-alcoholic fatty liver disease (NAFLD)-associated hepatocellular carcinoma (HCC). Methods: HCC and liver parenchyma features at MRI from 48 consecutive patients with NAFLD and histology proven HCC (mean ± SD; 4.5 ± 3.4 cm) were independently reviewed by three radiologists. Inter-rater agreement was determined by prevalence/bias-adjusted kappa. Hepatic fat signal fraction (FS%) was independently calculated. HCC features were compared by FS% at MRI using logistic regression analysis and histologic steatosis grade using Cochran-Armitage test for trend, stratified by cirrhotic liver morphology or histologic fibrosis stage. Receiver operating characteristic curves were generated to determine the sensitivity and specificity for major HCC features by FS%. Results: Major HCC features included arterial phase hyperenhancement (APHE) in 45 (93%), portal venous phase washout (PVWO) in 30 (63%), delayed phase washout (DPWO) in 38 (79%) and enhancing “capsule” in 34 (71%). Cirrhotic morphology was present in 22 (46%). Inter-rater agreement was 0.75 for APHE, 0.42–0.58 for PVWO, 0.58–0.71 for DPWO and 0.38–0.67 for enhancing “capsule”. There was an 18%, 14% and 22% increase in the odds of absent PVWO, DPWO and capsule appearance for every 1% increase in hepatic FS% in patients with non-cirrhotic liver morphology (p = 0.011, 0.040 and 0.029, respectively). Hepatic FS% ≥ 14.8% had a sensitivity and specificity of 64 and 100% for absent PVWO and 71 and 90% for absent DPWO in patients with non-cirrhotic liver morphology. Conclusion: Absent washout and capsule appearance are associated with increasing hepatic steatosis in patients with non-cirrhotic, NAFLD-associated HCC. Advances in knowledge: In patients with non-cirrhotic, non-alcoholic fatty liver disease (NAFLD)-associated hepatocellular carcinoma (HCC), absent HCC washout and capsule appearance are associated with increasing hepatic steatosis, thereby potentially impacting the noninvasive imaging diagnosis of HCC in these patients. Lack of washout or capsule appearance in steatotic livers at MRI may require alternative criteria for the diagnosis of HCC in patients with non-cirrhotic NAFLD.