A Technical Note on Portal Vein Reconstruction With Interposition Cadaveric Internal Iliac Vein Graft in an Infant With Biliary Atresia and Portal Vein Hypoplasia.

Biliary atresia (BA) represents a major indication for pediatric liver transplantation worldwide. Portal vein (PV) hypoplasia often poses technical challenges during transplantation, as it may increase the likelihood of thrombosis or anastomotic complications. We present the case of a nine-month-old infant with BA and failed Kasai portoenterostomy who underwent living donor liver transplantation. Severe PV hypoplasia necessitated interposition grafting. A 2 cm cryopreserved cadaveric internal iliac vein was used, anastomosed proximally to the superior mesenteric-splenic confluence and distally to the graft PV using 7/0 interrupted polypropylene sutures. Intraoperative Doppler confirmed portal flow of 25 cm/s with triphasic hepatic venous outflow. This case demonstrates the technical feasibility of cadaveric internal iliac vein interposition for PV reconstruction in infant BA, expanding the options for managing PV hypoplasia in pediatric liver transplantation.