Diagnostic and monitoring value of ultrasound, computed tomography angiography, and portal venography in surgical ligation of congenital extrahepatic portosystemic shunts.

ABSTRACT

PURPOSE: To investigate the diagnostic and monitoring value of ultrasound (US), computed tomography angiography (CTA), and portal venography in surgical ligation of congenital extrahepatic portosystemic shunts (CEPS) in children. METHODS: We retrospectively analysed different imaging examinations of 15 children with CEPS. Development of the portal vein before shunt occlusion, shunt location, portal vein pressure, main symptoms, diameter of the main portal vein, and location of secondary thrombosis after shunt occlusion were recorded. Final classification diagnosis was made by portal venography after shunt occlusion, and consistency with other imaging examinations in diagnosing development of the portal vein was calculated using Cohen's kappa. RESULTS: Compared with portal venography after shunt occlusion, US, CTA, and portal venography before shunt occlusion had poor consistency in showing the development of hepatic portal veins (Kappa value 0.091-0.194, P > 0.05). Six cases developed portal hypertension (40-48 cmH2O) during the temporary occlusion test, and US showed that portal veins gradually expanded after shunt ligation. Eight patients with haematochezia had inferior mesenteric vein (IMV)-iliac vein (IV) shunts. After surgery, secondary IMV thrombosis was observed in eight cases and secondary splenic vein thrombosis in four cases. CONCLUSION: Portal venography with occlusion testing is very important to accurately evaluate the development of the portal vein in CEPS. The portal vein needs to expand gradually, and partial shunt ligation surgery is necessary in cases diagnosed as portal vein absence or hypoplasia before occlusion testing to avoid severe portal hypertension. After shunt occlusion, US is effective in monitoring portal vein expansion, and both US and CTA can be used to monitor secondary thrombi. IMV-IV shunts can cause haematochezia and are prone to secondary thrombosis after occlusion.