Rationale and Objectives. This study was performed to determine whether ultrasound (US) performed with SonoVue, a
contrast agent that contains microbubbles filled with sulfur hexafluoride vapor, depicts differential patterns of contrast enhancement
in focal hepatic lesions.
Materials and Methods. Forty focal hepatic lesions (15 hepatocellular carcinomas [HCCs], 10 metastases, 11 hemangiomas,
and four focal nodular hyperplasias) in 39 patients were evaluated by means of US, color Doppler US, and contrastenhanced
US performed by using intermittent high-acoustic-power mode. Contrast-enhanced helical computed tomography
(11 patients) and US-guided fine needle aspiration (28 patients) were used as reference procedures. Contrast enhancement
patterns were defined by means of both subjective and objective analysis, and baseline and contrast-enhanced US scans
were reviewed offline.
Results. Thirteen of 15 HCCs, eight of 10 metastases, and all four hemangiomas with an atypical pattern at baseline US
were correctly characterized after SonoVue injection. Two of 15 HCCs and two of 10 metastases remained indeterminate,
with no characteristic baseline or contrast-enhanced patterns identified. Baseline US was essential in characterizing all
hemangiomas with a typical pattern (n 7), and color Doppler US with spectral analysis of tumoral vessels was essential
in characterizing focal nodular hyperplasia. The percentage of diagnostic agreement with reference procedures was significantly
increased (P .001) for contrast-enhanced US compared with baseline US.
Conclusion. Characteristic patterns of US contrast enhancement with SonoVue help in characterizing and differentiating
focal hepatic lesions.
