THE RAMIFICATION PATTERN OF PORTAL VEIN IN LEFT LOBE OF HUMAN LIVER STUDIED BY CORROSION CAST METHOD.

Abstract

INTRODUCTION: The aim of the study was to know the intrahepatic ramication pattern of portal vein in left lobe of liver & its variations. METHODS: 25 human fresh livers were obtained after autopsy and studied by corrosion cast method. Polymeric granules of butyl butyrate were dissolved in acetone and 20% homogenous solution was made. Solution was injected into portal vein and the injected liver was placed in 10 % formal saline for 24 hours at room temperature (20°C) for polymerization of infused butyl butyrate solution. Maceration of liver tissue achieved by whole-organ immersion in 1.8 N KOH solution at 68°C for 24 hrs. Each cast thus obtained was preserved in glycerin and details were studied. RESULTS: The length of the transverse part of Left portal vein (LPV) varies from 1.5 -3.7 cm (2.6 cm) while the length of umbilical part of LPV varied from 0.5 – 1.5 cm. (1.1cm.) and total length of LPV varies from 2.0 cm.-4.8cm.(3.7cm). Ramication of Left Portal Vein was described on the basis of its umbilical part. Two type of pattern observed Type I (Umbilical Part Turned Inferiorly) 60 % cases & Type II (Umbilical Part Turned Superiorly). For segment II - Cranio- lateral (CAL) branch originated from the convexity of the curved portion of the umbilical part 84 % cases while in 16 % it has originated from the transverse part of the LPV. Segment III- Caudo- lateral branch (CRL) originated from the convexity of the curved portion of the umbilical part of LPV in all the cases. Segment IV- From the concavity, Inferio – medial branch ran downward & medially while superior- medial branch ran superiorly & medially to supply the lower & upper part of segment IV respectively. The both superio- medial & inferio-medial branches were present in 13 of 25 cases (52 %), while only superior -medial branches were present in 16 of 25 cases (64 %) cases & only inferio-medial 21 of 25 cases (84%) in cases. In 5 of 25 cases (20 %), a common trunk has originated from the concavity of curved portion of the umbilical part then it divided in to superior-medial & inferio-medial branches to supply the segment IV. The number of portal branches to the caudate lobe (segment I) varied from 1 to 4 branches: most commonly from LPV (52 %), then portal vein (16%) & then right portal vein12% cases. At least one of these branches was always originated from LPV (100%). The number of the branches to supply the caudate lode was 2 as it observed in 56 %, while 3 braches in 16 % cases & 4 branches were present in only 8% of the cases. The ndings of present CONCLUSIONS: study on hepatic vasculature have immense importance in the eld of hepato-biliary surgeries.