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

•Portal venography with occlusion testing is very important to accurately evaluate the development of portal vein in CEPS.•Portal vein needs to expand gradually after shunt ligation, especially in cases diagnosed as portal vein absence or hypoplasia before occlusion test.•Ultrasound is an effective method to monitor portal vein expand and thrombosis after shunts occlusion.•Inferior mesenteric vein- iliac vein shunts can cause hematochezia, and prone to secondary thrombosis after occlusion.