Aim: To investigate the specific findings and characteristics of real-time contrast-enhanced ultrasound (CEUS) in hypoechoic hepatic hemangioma.
Methods: A total of 101 lesions in 83 patients were included. Analysis was made of the relationship between tumor size and CEUS enhance patterns in arterial phase, portal phase and delayed phase, phase changes, echoic changes in perfusion regression stage and filling defect.
Results: CEUS showed a lesion detection rate of 92.7%. In regression stage, only 46.5% lesions were fully filled. Enhancement of the lesions was categorized into Pattern I, peripheral nodular enhancement and centripetal filling (68.3%); Pattern II, peripheral ring enhancement and centripetal filling (27.7%); and Pattern III, overall rapid enhancement (4.0%). The most common phase changes were "fast-in slow-out" (74.3%). More than half (61.4%) lesions were hyperechoic in regression stage. Among all the lesions, 4 (3.9%) lesions regressed to hypo-echo in portal phase and 2(2.0%) in delayed phase). The frequent enhancement in tumors >3.0 cm was of Pattern I or II, "fast-in slow-out" or "slow-in slow-out" phase change, and hyperechoic or isoechoic change in perfusion regression stage, but in those ≤3.0 cm, the enhancement was of Pattern III, "fast-in fast-out" phase change and hypoechoic change in perfusion regression stage. The differences were statistically significant (p < 0.05). The percentage of lesions with complete filling on CEUS in the larger hypoechoic hepatic hemangiomas was significantly lower than that of smaller ones (p < 0.01).
Conclusions: CEUS has high diagnostic value in hypoechoic hepatic hemangiomas mainly characterized by peripheral nodular or ring enhancement, centripetal filling, and "fast-in slow-out" and "slow-in slow-out" phase changes.
Keywords: Hypoechoic hepatic hemangioma; contrast-enhanced ultrasound (CEUS); enhancement pattern.