Sutureless portal vein reconstruction in porcine orthotopic liver transplantation using a microvascular coupler: A randomized study with artificial intelligence-assisted histopathology

Figure 1 Sequential steps of microvascular anastomotic coupler application. A: Align the transected portal vein ends and select the coupler size with a vascular gauge (outer diameter matched to vessel caliber); B: Open the coupler and expose the barbed pins; C: Evert each vein edge and seat the wall evenly onto the pins, ensuring full thickness capture without intimal folding; D: Repeat pinning on the contralateral stump with circumferential, evenly spaced engagement; E: Approximate the rings and lock using the mechanical rotation tool until the audible/visual stop is reached; F: Inspect for uniform apposition, absence of gaps/bleeding, and confirm lumen patency; G and H: Schematics showing pressure and tension distribution after closure, highlighting circumferential load sharing and anti-slippage by the barbed pins. P: Pressure; T: Tension; S: Sectional.