CONTRAST-ENCHANCED ULTRASOUND IN THE DIFFERENTIAL DIAGNOSIS OF FOCAL NODULAR HYPERPLASIA AND HEPATIC ADENOMA

Aim. To increase the effectiveness of the differential diagnosis of benign focal lesions of the liver using contrast-enhanced ultrasound (CEUS).

Materials and methods. A retrospective analysis of the examination results of 37 patients with morphologically confi rmed liver benign tumors was carried out. According to the morphological data, the patients were divided into two groups: 22 patients with focal nodular hyperplasia (FNH) and 15 patients with hepatocellular adenoma (HCA). All the patients underwent multiparametric ultrasound examination using CEUS.

Results. According to the obtained data, despite the nearly equal intensity of fi lling FNH and HCA with a contrast agent (96% and 80%, accordingly), FNH is characterized by an earlier contrasting (WASH IN) pattern in the arterial phase (AF), with the ‘onset of contrasting in the focus’ parameter being signifi cantly different from HCA (p<0.05). Specifi c signs of FNH included the following: the spoke-wheel pattern and an increased intensity of ultrasound contrast agent (USCA) accumulation — 96% of cases; ‘center-to-edge’ fi lling — 86% of cases. WASH-OUT is not a typical sign of FNA. A complete (100% of cases) and intensive (80% of cases) centripetal (80% of cases) fi lling is characteristic of HCA. No specifi c types of vascular pattern were observed. In 6 (40%) patients, WASH-OUT and ‘relative hyperechoic’ were detected in the portal phase.

Conclusion. CEUS is established to be an effective method of the differential diagnosis of FNH and HCA.