Peer-reviewed article

Key factors for predicting outcomes one year after Meso-Rex bypass surgery and optimizing the surgical plan in children with extrahepatic portal vein obstruction.

Fan He, Zhe Wen, Fuyu You, Jieqin Wang, Jinwei Chen et al. · 13 Aug 2026

Abstract

OBJECTIVES: To analyze the factors for predicting 1-year outcomes and optimize surgical planning for Meso-Rex bypass (MRB) in children with extrahepatic portal vein obstruction (EHPVO). MATERIALS AND METHODS: From October 2014 to July 2024, children with EHPVO after MRB were retrospectively analyzed. The number of MRB, the type of bypass vessel, and the position of the lower anastomosis were collected. Predictive variables include the diameter of the connection between the left and right portal veins, the Rex vein (RV) diameter, the number of RV branches, the diameter of the thickest RV branch, and the bypass-to-superior mesenteric vein (SMV) angle, which were measured by Contrast-enhanced CT (CECT) one week after MRB. The upper and lower anastomotic stenosis were diagnosed by Ultrasound and CECT one year after MRB. RESULTS: A total of 153 children (median age 72 months, 87 males) were included in this study. Univariate factors include the number of MRBs, the type of bypass vessel, and CECT variables (except the diameter of the thickest RV branch). Numbers of MRB and RV branches were retained in the final model for upper anastomotic stenosis. The combination of MRB > 1 and RV branches ≤ 4 predicts it post-MRB with 75% sensitivity, 86.4% specificity, and an area under the receiver operator characteristic curve (AUC) of 0.832. The bypass-to-SMV angle ≤ 110° predicts lower anastomotic stenosis after MRB with 90% sensitivity, 73.39% specificity, and AUC 0.847. CONCLUSIONS: Associated factors are useful for early postoperative risk stratification. Moreover, the type of bypass vessel and the bypass-to-SMV angle could be used to inform future surgical technique refinement. KEY POINTS: QuestionWhich factors predict 1-year outcomes and optimize surgical planning for MRB in children with EHPVO? FindingsAssociated factors include bypass-to-SMV angle, number of MRB, RV branches and diameter, left-right portal vein connection diameter, and type of bypass vessel. Clinical RelevanceAssociated factors are useful for early postoperative risk stratification. Moreover, the internal jugular vein as the bridge vessel and the bypass-to-SMV angle > 110° could be used to optimize the surgical plan for a better outcome.