Assessment of Hepatocellular Carcinoma Vascularity: Comparison of Contrast-enhanced Coded Harmonic Ultrasound with Harmonic Power Doppler Ultrasound

Abstract

The aim of this study was to evaluate contrast-enhanced coded harmonic ultrasound (CHUS) in the depiction of the vascularity of hypervascular hepatocellular carcinomas (HCCs) by comparing it with that of contrast-enhanced harmonic power Doppler ultrasound (HPDUS). Contrast-enhanced CHUS was prospectively performed in 17 consecutively collected hypervascular HCCs (mean diameter, 3.4 cm; range, 1.8–7.8 cm) using the Coded Harmonic Angio mode of a LOGIQ 700 Expert unit and a 2 to 4 MHz curved linear-array probe. This was conducted using a microbubble contrast agent (Levovist®) and interval-delay scanning (scan interval, 20–30 s; scanning time, 2–5 s). All patients also underwent contrast-enhanced HPDUS, and the results were compared in terms of the depiction and degree of enhancement of tumor vascularity (feeding vessels, intratumoral macrovessels, intratumoral microvessels, and tumor staining), and the presence of artifacts. There was no significant difference between CHUS and HPDUS in depiction of tumor vascularity in terms of feeding vessels, intratumoral macrovessels and intratumoral microvessels. CHUS, however, was superior to HPDUS in terms of tumor staining ( p = 0.008). The degree of tumor vascularity enhancement was superior with CHUS in depicting tumor staining ( p = 0.001), but HPDUS was better in depicting intratumoral macrovessels ( p = 0.039). CHUS was artifact-free, while several artifacts were seen in all HCCs examined with HPDUS. Our results suggest that CHUS is capable of depicting tumor vascularity of hypervascular HCCs and is superior to HPDUS. Contrast-enhanced CHUS may be useful, therefore, in evaluating tumor vascularity of HCCs.