Evaluation of Diagnostic Accuracy of CEUS for HCC Diagnosis

Inclusion Criteria: * High risk group of developing HCC * hepatic nodule equal to or larger than 1cm on ultrasound or computed tomography (CT) * newly detected nodule (equal to or larger than 1cm, at least 2cm distance from radiofrequency ablation (RFA) site or resection margin) in patients with history of hepatic resection or RFA for HCC AND in remission more than a year * scheduled for gadoxetic acid-enhanced liver MRI * signed informed consent Exclusion Criteria: * hypersensitivity for ultrasound contrast media * pregnancy * history of recent treatment for HCC in a year * standard of reference is not available * severe cardiopulmonary disease (right to left shunt, severe pulmonary hypertension, uncontrolled hypertension, etc)