To elucidate the efficacy of contrast-enhanced ultrasonography in hepatocellular carcinoma, we studied the vascularity (tumoral vascular image and stain) of hepatocellular carcinomas, placing special emphasis on the vascular images using the systemically administered Levovist in conjunction with harmonic B-mode vascular imaging. The study included 24 nodules in 17 patients: 11 men and 6 women aged 62 to 88 years (mean, 72.6 years). Nodules averaged 22.5賊16.6 mm in diameter (range, 9 to 71 mm). Ultrasonographic studies were carried out with a GE LOGIQ 700 EXPERT ultrasound system. The image was obtained with a 348 C convex transducer (2 to 4 MHz) and a preinstalled Coded Harmonic Angio mode ultrasonographic system. Mechanical index was 0.6 to 0.8 (autofocused to provide high image quality). Acoustic power was set to its maximum level (100%). The focus point was set at or slightly below the center of the tumor. After receiving a bolus injection of Levovist, the patient underwent approximately 20 to 30 seconds of real-time imaging and was then scanned at 1-second intervals. Vascular images obtained using contrast-enhanced ultrasonography were classified as pattern 1, unenhanced; pattern 2, vascular image alone; pattern 3, vascular image and partial stain; or pattern 4, vascular image and strong stain. We further studied diameter, tumor depth, and Doppler findings from each pattern before enhancement. The vascularity images included pattern 1, three (12.5%) nodules; pattern 2, one (4.1%) nodule; pattern 3, seven (29.2%) nodules; and pattern 4, 13 (54.2%) nodules. Mean diameter of the 24 tumors by pattern was 12.3賊3.1 mm (MV賊SD) (range, 9 to 15 mm), 9 mm, 15.7賊5.5 mm (8 to 21 mm), and 29.6賊19.7 (9 to 71 mm), respectively. Mean tumor depth by pattern was 53.3賊15.3 mm (range, 40 to 7 mm), 60 mm, 51.4賊24.1 mm (30 to 90 mm), and 56.9賊18.9 mm (30 to 100 mm), respectively. Vascular signals were obtained with pre-enhanced Doppler US in 3 nodules in pattern 3 (43%) and 5 nodules in pattern 4 (38%). Contrast-enhanced ultrasonography with Coded Harmonic Angio mode and administration of Levovist was useful in evaluating vascularity of hepatocellular carcinoma.