Usefulness of the Contrast‐Enhanced Ultrasound Liver Imaging Reporting and Data System in Diagnosing Focal Liver Lesions by Inexperienced Radiologists

Objectives To evaluate the usefulness of the contrast‐enhanced ultrasound (CEUS) Liver Imaging Reporting and Data System (LI‐RADS) in diagnosing focal liver lesions (FLLs) by inexperienced radiologists. Methods Images and clinical data from 258 patients at risk for hepatocellular carcinoma who underwent CEUS were collected retrospectively. Two trained inexperienced radiologists and 2 experienced radiologists reviewed all CEUS clips. Each inexperienced radiologist assigned a CEUS LI‐RADS category for each observation and labeled it benign or malignant independently. Each experienced radiologist labeled each lesion malignant or benign independently using a conventional diagnostic method. Interobserver agreement of CEUS LI‐RADS was analyzed by the κ test. The overall diagnostic accuracy of the LI‐RADS category and conventional diagnosis was described by the sensitivity, specificity, positive predictive value, and negative predictive value. All test results were considered significant at P