Benefits of contrast-enhanced sonography for the detection of liver lesions: Comparison with histologic findings

OBJECTIVE. The objective of our study was to compare the usefulness of contrast-enhanced sonography with baseline sonography in detecting malignant liver lesions. SUBJECTS AND METHODS. This prospective study included 116 patients. All patients underwent a preoperative conventional sonography examination followed by sonography after injection of contrast agent combined with the use of perfusion software (vascular recognition imaging or pulse subtraction imaging). Histopathologic analysis was the reference standard used to compare the diagnostic value of baseline sonography versus contrast-enhanced sonography. RESULTS. Eighty-two patients underwent hepatic surgery, 31 did not because of disseminated lesions, and the remaining three patients did not meet inclusion criteria. Three hundred six surgically proven lesions were taken into account for comparison of the two techniques: 147 were detected on baseline sonography and 177 on contrast-enhanced sonography. Histopathologic analysis revealed 233 malignant and 73 benign lesions. Sensitivity and specificity were improved on contrast-enhanced sonography compared with baseline sonography for the detection of malignant lesions: 68.7% versus 58.8% and 67% versus 50.7%, respectively. Contrast-enhanced sonography detected 23 additional malignant lesions that had been seen as lacuna at the portal venous phase and characterized as 19 benign nodules, thus improving the performance of sonography in 13.7% of the cases. CONCLUSION. Contrast injection improved the sensitivity and specificity of baseline sonography and should be performed in routine practice if hepatic surgery is being considered for the management of liver lesions.