Emilio Quaia MD, Presenter: Nothing to Disclose

Riccardo Pizzolato MD, Abstract Co-Author: Nothing to Disclose

Marco Cavallaro, Abstract Co-Author: Nothing to Disclose

Biagio Cabibbo, Abstract Co-Author: Nothing to Disclose

Maria Assunta Cova MD, Abstract Co-Author: Nothing to Disclose

To assess whether solid focal liver lesions detected in a non-cirrhotic liver and presenting atypical enhancement on contrast-enhanced cross-sectional imaging techniques - CT and/or MR - may be effectively characterized by contrast-enhanced ultrasound (CEUS).  

Fifty-five incidental solid focal liver lesions (1–5 cm in diameter) in 25 non-cirrhotic patients (20 female, 5 male; age±SD, 55±10 years) were considered indeterminate after the on-site analysis of multiphase contrast-enhanced CT and/or MR images due to the evidence of persistent hypovascular appearance or atypical enhancement pattern. Each lesion was subsequentlyt scanned by CEUS after sulphur hexafluoride-filled microbubble injection during arterial (15-30 seconds), portal-venous phase (40-75 seconds), and late phase (80-180 seconds from microbubble injection). Two blinded independent readers retrospectively reviewed contrast-enhanced cross-sectional images before and after CEUS cine-clips analysis, and were asked to classify each lesion as malignant or benign according to standard diagnostic criteria based on the contrast enhancement patterns during the arterial phase, and lesion vascularity during portal venous and late phase compared to adjacent liver parenchyma. Diagnostic accuracy and confidence (area -Az- under receiver operating characteristic curve) were assessed by using imaging 6-12 month follow-up (n=48 lesions) or histology (n=7 lesions) as reference standards.

On CEUS peripheral nodular (n=25 lesions), absent (n=18), rim-like (n=8 lesions), or diffuse contrast enhancement (n=4) were identified during the arterial phase with lesion persistent hypovascularity during portal venous and late phase both in benign and malignant lesions. The additional review of CEUS after CT/MR images improved significantly (P<.05) the diagnostic performance (overall accuracy before vs after CEUS review=48% vs 85% -reader 1- and 51% vs 87% -reader 2-) and confidence (Az before vs after CEUS review =0.820 vs 0.968 -reader 1- and 0.831 vs 0.978 -reader 2-).

CEUS improved the characterization of solid focal liver lesions appearing indeterminate on cross-sectional imaging by identifying some specific enhancement patterns.

CEUS revealed an higher diagnostic performance than CT and MR in those lesion appearing persistently hypovascular in all dynamic phases avoiding biopsy in a significant number of these lesions.

Quaia, E, Pizzolato, R, Cavallaro, M, Cabibbo, B, Cova, M, Characterization of Solid Tumour Detected in a Non-cirrhotic Liver and Presenting Atypical Enhancement on CT or MR: Assessment of the Additional Diagnostic Value of Contrast-enhanced Ultrasound.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9002133.html