Characterization by biopsy or CEUS of liver lesions guided by image fusion between ultrasonography and CT, PET/CT or MRI.

ABSTRACT

PURPOSE: The aim of this study was to show the number of cases in which the use of fusion-guided ultrasonography (US) provided conclusive diagnosis of lesions in the liver seen on CT or MRI or PET/CT. A lesion is defined as a region that has suffered damage due to injury or disease. MATERIALS AND METHODS: Forty patients of whom 34 had confirmed neoplastic disease, referred to US evaluation or US-guided biopsy of liver lesions seen on CT (n = 35), MRI (n = 2) or PET/CT (n = 3), were prospectively included in the study. We used a LOGIQ prototype system with incorporated software for fusion imaging, and a convex-array 4 MHz transducer (GE Healthcare, Chalfont St. Giles, UK). All patients were initially examined with B-mode US, then by fusion-guided US and for some patients also with CEUS. All patients received follow-up after at least one year. RESULTS: Twenty-six lesions were initially indistinguishable with US. Of these, 9 became visible with fusion-guided US and another 4 became visible with CEUS, which facilitated a final diagnosis in 11 of these 13 patients. The median tumor size for all lesions included in the study was 1.5 cm (interquartile range 1.0 - 2.4). There was no statistically significant difference in tumor size between the groups. CONCLUSION: We have successfully demonstrated an increase in the characterization of liver lesions by using fusion-guided US compared with conventional B-mode US.