Accuracy of Gray-Scale and Color Doppler Sonography in Diagnosis of Hepatic Hemangioma, Hepatocellular Carcinoma and Liver Metastasis.

Background/objective: distinguishing cavernous hemangioma from malignant neoplasms represents a diagnostic challenge. knowledge of the entire spectrum of gray-scale ultrasonography (us) and color doppler appearances of these tumors is important. the objective of this study was to determine the diagnostic accuracy of gray-scale us and color doppler appearances of liver tumors.patients and methods: 88 patients with 93 focal hepatic lesions were prospectively studied with gray-scale and color doppler us. the final diagnoses of the liver lesions as confirmed by pathology or 99mtc-red blood cell scintigraphy were 41 hemangiomas, 15 hepatocellular carcinomas (hccs) and 37 metastases.results: 87.8% of hemangiomas and 66.7% of hccs were hyperechoic, while 54.1% of metastases were hypoechoic. in lesions < 3 cm in diameter, the sensitivity and specificity of the hyperechoic pattern for differentiation of hemangioma from metastasis and hcc were 94.1% and 80.0%, respectively. they were higher than the lesions with a diameter >= 3 cm (83.3% and 45.9%, respectively, both p=0.001). posterior acoustic enhancement was seen in 78% of hemangiomas (p<0.001), as compared to 24.4% in metastases and 13.3% in hccs. 10 hemangiomas had an echogenic rim. the peripheral hypoechoic rim, named as the target sign, was seen in 37.8% of metastases, 26.7% of hccs and 2.4% of hemangiomas (p<0.001). most hemangiomas (85.4%) showed no lesional blood flow, while most hccs (80%) had both intraand peri-lesional vascularity (p<0.001). there was intratumoral blood flow in 86.7% of hccs. lesional flow, whether intratumoral or peritumoral or both, was seen in all 14 patients with hcc while absence of the lesional flow was not noted in any of the hccs.conclusion: most hemangiomas had no detectable blood flow in color doppler us. almost all hccs had intra- and/or peri-tumoral vascularity in color doppler sonography, so the probability of hepatocellular carcinoma is low in a hepatic mass without intra- or peri-lesional vascular blood flow. so these findings together with morphological criteria may help narrow down the differential diagnosis in certain clinical conditions.