This retrospective study investigates the role of CEUS in evaluating liver lesions with atypical characteristics on contrast-enhanced CT or MRI. All patients enrolled in the study underwent contrast-enhanced ultrasound. All CEUS exams were performed, recorded, and analyzed by two experienced operators (>10 years of experience with abdominal US and CEUS). Based on CEUS characteristics, atypical nodules will be categorized according to CEUS LI-RADS (LR) classification. If the analyzed nodule shows a typical hallmark on CEUS (LR-5), that is arterial phase hyperenhancement with late-onset (>60 s) washout of mild intensity, it is definitively considered HCC and have been treated appropriately. Categories LR-3 and LR-4 comprise nodules with different combinations of arterial and venous phase enhancement features, expected to correspond to an intermediate or high probability of lesions to be HCC. Patients with LR-3 or LR-4 nodules underwent follow-up; in some cases they underwent biopsy.~LR-M is used to classify high-probability malignant lesions but nonspecific for HCC; these nodules underwent biopsy for further characterization.
The present study aims to investigate the role of CEUS in evaluating liver lesions with atypical characteristics on contrast-enhanced CT or MRI. All patients enrolled in the study underwent contrast-enhanced ultrasound. Based on CEUS characteristics, atypical nodules will be categorized according to CEUS LI-RADS classification.