Contrast-enhanced Harmonic Power Doppler Ultrasonography: Improved Depiction of Vascularity and Characterization of  Flow Pattern in Hepatocellular Carcinoma.

Baek,  Hyung Chul; Yoon,  Kwon Ha; Kim,  Chang Guhn; Park,  Ki Han; Won,  Jong Jin

Journal of Korean Society of Medical Ultrasound 2000;19(4): 233-238.

Contrast-enhanced Harmonic Power Doppler Ultrasonography: Improved Depiction of Vascularity and Characterization of Flow Pattern in Hepatocellular Carcinoma.

Hyung Chul Baek, Kwon Ha Yoon, Chang Guhn Kim, Ki Han Park, Jong Jin Won

Department of Radiology, Wonkwang University School of Medicine.

Published online: January 1, 2001.

ABSTRACT

PURPOSE: To evaluate the value of contrast-enhanced harmonic power Doppler ultrasonography (PDUS) in depiction and characterization of tumoral vascularity in hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Thirty-three patients with HCC were prospectively evaluated with harmonic PDUS before and after injection of the contrast agent SH U 508A (2.5g, 300 mg/ml). Unenhanced and serial dynamic scans at 15, 30, 45, 60, 90, 120, 150, 180, 240, 300 seconds after injection of contrast agents were obtained using a tissue harmonic technique with power Doppler imaging. The tumoral vascularity was expressed as percentage of power Doppler area, which was measured quantitatively by a computerized program (Ultrasonic Imaging Tool; Soongsil University, Seoul, Korea). The grade (0, no signal; 1, less than 5%; 2, 5-25%; 3, more than 25%) and flow pattern (intratumoral, detour, basket, and mixed) of tumoral vascularity were analyzed. Peak time of contrast-enhancement was measured on each tumor. RESULTS: After injection of contrast agent, tumoral flow signals increased in all lesions (100%). At unenhanced harmonic PDUS, flow signals were detected in 17 HCCs (52%); 15 tumors (46%) demonstrated grade 1 vascularity; and two (6%), grade 2. At contrast-enhanced harmonic PDUS, all tumors were detected vascularity; five (15%) were grade 1; eight (24%), grade 2; and 20 (61%), grade 3. Flow patterns were demonstated as follows at unenhanced harmonic PDUS; intratumoral pattern in 13 tumors (76%), detour in 2 (12%), and basket in 2 (12%). After injection of contrast agent, intratumoral pattern in 7 tumors (21%), detour 0 (0%), basket in 3 (9%) and mixed in 23 (70%) were demonstrated. Peak time of enhancement after injection of contrast agent was 30- 90 seconds in majority of the patients. CONCLUSION: Contrast-enhanced harmonic PDUS would be valuable in depiction of vascularity and characterization of flow pattern in HCC.

Keywords: Liver neoplasms; Ultrasound (US), contrast media; Ultrasound (US), power Doppler studies