Purpose:
Preoperative qualification for Meso-Rex bypass (MRB) in children with extrahepatic portal vein obstruction integrates Doppler ultrasonography, computed tomography/magnetic resonance imaging, portomesenteric inflow and conduit assessment, and surgical judgement. Retrograde wedged hepatic venous portography (RHVP) has a distinct role: direct angiographic evaluation of intrahepatic portal venous anatomy. This study presents a structured RHVP framework focused on that component.

Material and methods:
This retrospective single-centre study included consecutive children referred as potential MRB candidates and evaluated with RHVP between January 2023 and June 2026. The RHVP analysis assessed the transverse and umbilical portions of the left portal vein, left-right portal venous communication, peripheral branches, collaterals, veno-venous communications, calibre, filling defects, and stenoses. Findings were correlated with intraoperative observations and early Doppler-confirmed graft function.

Results:
Forty-seven RHVP examinations were performed in 45 patients; 2 required repeat RHVP and 1 underwent additional direct transhepatic portography, not counted as RHVP. Median age at RHVP was 11.3 years (range 0.4-17.7); the cohort included 18 girls and 27 boys. Access was via the right internal jugular in 29 and upper extremity in 18 examinations; no RHVP-related complications occurred. Fifteen patients were disqualified, 4 for surgical/clinical reasons and 11 on RHVP assessment. Thirty patients underwent MRB; 27 had early successful hepatopetal graft flow and 3 were unsuccessful.

Conclusions:
Structured multiparametric RHVP complements type-based classifications by documenting mandatory eligibility criteria together with additional findings that may affect surgical complexity, portal inflow, and early graft function. It supports interdisciplinary communication and future validation of imaging-derived modifiers in borderline anatomy.