Endovascular stenting for late-onset stricture of interposed portal vein conduit following pediatric liver transplantation

Portal vein (PV) interposition using a vein homograft can induce various PV complications. We present a case of pediatric living-donor liver transplantation (LDLT) showing late-onset stenosis of the interposed PV conduit, which was treated by endovascular stenting. The patient was an 11-month-old female infant weighing 7.8 kg with hepatoblastoma. She was partially responsive to systemic chemotherapy. Thus, LDLT was performed to treat the tumor. The living donor was the 34-yearold mother of the patient. After non-anatomical size reduction, the weight of the reduced left lateral section graft was 235 g, with a graft-to-recipient weight ratio of 3.0%. Recipient hepatectomy was performed according to the standard procedures of pediatric LDLT. The graft PV was anastomosed with an interposed external iliac vein homograft. The liver graft was partially accommodated in the right subphrenic fossa, resulting in dextro-plantation. The patient recovered from LDLT operation. However, at 4 months after transplantation, PV conduit stenosis occurred. This PV stenosis was initially treated with balloon dilatation, but the stenosis did not disappear. Finally, endovascular stenting was performed. The patient has been doing well for 3 years 6 months after transplantation with patent PV flow. In conclusion, interposition of PV conduit carries risk of PV conduit stenosis, hence it is necessary to perform regular follow-up studies for PV patency for a prolonged period. Radiological intervention is the only therapeutic treatment for such PV conduit stenosis.