Single imaging modality evaluation of living donors in liver transplantation: Magnetic resonance imaging

Background. Liver graft size, anatomy of the bile duct and the vascular inf low and outflow are essential for living related liver transplantation (LRL T). Preoperative delineation of those variations that would change the oper ative procedure to achieve a successful result especially in an emergency c ondition. Purpose. Our aim was to develop a rapid and noninvasive imaging diagnostic method for the detection of anatomical variants that is mandatory for a saf e operation when selecting potential liver transplant living donors. We use d a different magnetic resonance (MR) imaging technique, which enabled to u s to exploit the anatomical landmark of the liver, signal enhancement of bl ood flow in the abdomen, and the intrahepatic biliary routes inside the liv er. Then, with the help of Advantage Window workstation reconstruction, the reconstructed single vascular or biliary systems were displaced in a three -dimensional fashion and the whole examination finished within 30 min. Methods. Modification of the standard MR technique was performed on a super conductive 1.5T whole body image scanner, MR arteriogaphy, venography, and cholangiography with three-dimensional reconstruction in evaluating the ana tomy of the hepatic arteries, hepatic veins, portal venous system, bile duc ts, and liver size in potential liver transplant living donors. These anato mical structures were compared with traditional imaging methods. Results. In all 38 cases, as well as delineation of the portal vein detail to the segmental level was satisfactorily obtained in this MR study. The im ages were well displayed in a three-dimensional fashion, which had good cor relation with images from traditional imaging modalities and operative find ings. In 86.8% cases, the MR arteriography was well matched with the celiac angiography. Of those 17 operative cases, estimation of liver volume was w ell correlated with the liver graft within 3.9-12.5% variation. In the majo r hepatic vein, we obtained 100% accuracy and 88.2% in the minor branches. Of 12 donors received intraoperative cholangiography during liver donation, good correlation of biliary anatomy was achieved. One donor was excluded f rom graft donation due to the complicated arterial supply to the left liver . According to the anatomical variation, surgical procedures in graft harve sting and anastomosis were readjusted and no major complications were found in those donors and all recipients survived after liver transplantation. Conclusion. MR volumetry, venography, angiography, and cholangiography with three-dimensional reconstruction is sufficient for all major imaging evalu ation. It may replace the traditional conventional catheter angiography, co mputed tomography, sonography and endoscopic retrograde cholangiography as a single investigation in the evaluation of the potential liver transplant donors. Angiography is only valuable in suboptimal cases and intraoperative cholangiography is only performed in biliary ductile variants.