Features superb microvascular imaging (SMI) technique in the differential diagnosis of focal liver formations

Purpose: To evaluate the diagnostic accuracy of superb microvascular imaging (SMI) in the differential diagnosis of focal liver lesions tumors in clinical practice.

Materials and methods: 50 patients with a different focal hepatic lesions were examined by typical B-mode ultrasound and SMI and were included in the trial. All results were compared to histology after biopsy or in some cases to computer tomography (CT) or magnetic resonance imaging (MRI).

Results: In 3 cases (6%) was focal nodular hyperplasia (FNH) with typical sonographic symptoms (such as central scare and spoke-wheel vessel pattern). The final diagnosis of FNH was verified by lesion biopsy. 10 patients (20%) had hepatocellular carcinoma. These tumors were single and had heterogenic structure, echogenicity was equal to the liver, mean size 4.2 cm ± 1.1 cm and pathological chaotic vascularization with high intensity. 17 (34%) were metastatic tumors. Almost all metastases had multiple character and has various echogenicity but most of them were hyperechoic (size variated from 1.5 cm to 5.4 cm). Most they had smooth clear contours, moderate blood flow located in a chaotic manner. In all cases the primary tumor was found on CT. 15 person (30%) had haemangioms (size from 0.6 cm to 4 cm). In these cases lesions were hyperechoic, with homogenius structure. SMI had shown diffuse bloodstream with low intensity. 6 (12%) hyperechoic focuses (size from 1.5 cm to 6.0 cm) had no blood vessels in colour Doppler and SMI, and were regarded as hotbeds of uneven fatty infiltration, which was confirmed by CT.

Conclusion: SMI is very useful method of diagnostic and can be the final diagnostic exam without contrast enhansed ultrasound in suspect of FNH and allows to differentiate benign and malignant lesions in liver, and also will redice the number of biopsies.