How Useful is Contrast Enhanced Ultrasonography for the Characterization of Focal Liver Lesions?

Aim: Focal liver lesions (FLLs) are quite frequently discovered in daily practice at routine ultrasound. The aim of our study is to present a single centre experience concerning the use of contrast enhanced ultrasound (CEUS) in the characterization of FLL and to find when one can avoid using other expensive imaging modalities such as contrast enhanced CT or MRI. Method: We performed a prospective, single centre study during September 2009 - April 2010, and we evaluated 379 FLLs. A CEUS examination was considered conclusive if the FLL had a typical enhancement pattern according to the EFSUMB guidelines. Results: From the 379 cases with FLL, 198 (52.2%) were patients without known liver disease and 181 (47.8%) with known chronic liver disease (156 had cirrhosis, 25 chronic hepatitis); in 296/379 cases (78.1%) CEUS was conclusive. CEUS allowed the positive diagnosis of benign vs. malignant lesion in 261/294 (88.8%) de novo FLLs (CEUS performed for the first time), while in 33 (11.2%) cases it was inconclusive and could not differentiate between benign or malignant lesions. The CEUS results included 129 (49.4%) benign lesions and 132 (50.6%) malignant. Conclusion: CEUS was conclusive in approximately 80% of the FLLs and the benign or malignant character of a lesion was demonstrated in about 90% of cases. Thus, when faced with an uncharacteristic FLL on standard ultrasound examination, our local strategy is to perform CEUS as a first-line investigation, thus avoiding other expensive examinations.