Decrease in accumulation of ultrasound contrast microbubbles in non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH) is one of the representative liver diseases in developed countries. Diagnosis of NASH is dependent on histological findings from liver biopsy. The usefulness of contrast ultrasound with Levovist for diagnosis of NASH is described. 2.5 g of ultrasound contrast agent Levovist was injected intravenously. The liver was scanned at 5, 10, 15, 20, 30, 40 and 50 min and changes in microbubble accumulation were evaluated. The signal intensity from regions of interest (ROI) on the contrast images was measured and estimated using time intensity curves (TICs). Twenty-one patients with NASH, 33 with non-alcoholic fatty liver disease (NAFLD) and 10 healthy volunteers (HV) were studied. The signal intensity was measured quantitatively at 5 and 20 min after injection. There was a statistically significant decrease in NASH, when compared with NAFLD and HV groups. These changes in signal intensity were not correlated to the degree of fibrosis and steatosis in histological study. The sensitivity, specificity and overall accuracy obtained from the receiver operating characteristic (ROC) curve were 100% when the cut-off value was set at 43.6 of signal intensity at 20 min. The Levovist contrast study is a useful screening examination which picks up NASH among fatty liver patients.