Evaluation of intrahepatic portal vascular system and its perfusion according to Doppler ultrasound and superb microvascular imaging in children with extrahepatic portal hypertension

Abstract

Introduction: We aimed to study the features of intrahepatic portal vascular system and its perfusion using the Superb Microvascular Imaging (SMI) in children with extrahepatic portal hypertension. Method: Twenty pediatric patients with extrahepatic portal hypertension who underwent SMI with an Aplio 500 ultrasound system (Toshiba Medical Systems, Tokyo, Japan) were enrolled in this study. The subjects underwent conventional ultrasound examinations, including Doppler imaging followed by SMI. Standard imaging and SMI findings were compared. Result: The mean age of patients was 8.77±1,05 years. Before the shunt surgery, according to Doppler US hepatopetal flow on extrahepatic portion of portal vein was Vmpeak= 19.6 ± 1.51 cm/s. But it was impossible to determine patency of intrahepatic branches of portal vein. According to the SMI only in one case intrahepatic portal venous system, especially in the left lobe was irregular. In all other observations the intrahepatic branches of the portal vein and its segmental branches were patent. SMI characteristics of left portal vein in five patients were: d = 3±0.45 mm, the blood flow was Vmpeak = 7.25±0.16 cm/s. Conclusion: Superb microvascular imaging is especially useful for depicting the microvascular flow, and our initial experience shows that SMI was superior to Doppler imaging for depicting left portal vein at Rex recessus and estimating perfusion.