Thickness Reduction Versus Conventional Left Lateral Sector Strategies in Children Below 8 kg Undergoing Living Donor Liver Transplantation

BACKGROUND: Liver transplantation in children weighing < 8 kg carries a high risk of graft-recipient size mismatch, particularly excessive graft anteroposterior (AP) thickness, which may impair abdominal closure and graft perfusion. Graft thickness reduction (TR) has been proposed to address this issue; however, objective criteria guiding its indication remain poorly defined. This study compared outcomes between thickness-reduced grafts and left lateral segment (LLS) grafts and explored factors associated with TR use. METHODS: We retrospectively analyzed 79 primary living-donor liver transplants performed in recipients weighing < 8 kg between January 2017 and July 2025. Patients were divided into LLS/standard-reduced LLS (LLS/SR-LLS, n = 46) and thickness reduction by anterior hepatic resection (TR-AHR, n = 33). Recipient, donor, intraoperative, and postoperative variables were compared. RESULTS: Recipients in the TR-AHR group were younger, while body weight and PELD were similar between groups. Donors in the TR-AHR group were more frequently male and had higher body weight and BMI. TR-AHR achieved significantly lower final graft weight, graft-to-recipient weight ratio, and AP diameter. Rates of primary abdominal closure, ICU and hospital length of stay, vascular and biliary complications, and patient survival were comparable. Donor male sex, higher donor body weight and BMI, increased DWRWR, larger estimated AP diameter, and higher estimated GRWR were associated with TR-AHR use. CONCLUSION: TR-AHR is a safe and effective strategy to manage graft-recipient size mismatch in recipients < 8 kg, achieving favorable graft dimensions without increasing morbidity. Identified variables should be interpreted as practical markers rather than formal selection criteria. Larger multicenter studies are needed to define standardized indications and long-term outcomes.