Review of Donor Anatomy Prior to Living Donor Liver Transplantation Using Magnetic Resonance Imaging

Abstract

Purpose This study aimed to investigate vasculobiliary anatomical variations in living liver donors (LLDs) during pretransplant evaluation using magnetic resonance imaging (MRI). The accuracy of MRI in estimating graft weight was also evaluated. Methods Pre-operative MR imaging data of 100 LLDs were retrospectively assessed, and variations in the biliary, arterial, and venous systems were evaluated. Surgical records were used to identify discrepancies between MRI biliary findings and intra-operative cholangiograms. The image quality was classified as poor, fair, or good. The MRI-estimated weight was compared with the actual explant weight measured during surgery. Results Ninety-seven right lobe hepatectomies and 3 left lobe hepatectomies were performed, with 19 patients exhibiting classic anatomy in all three components. Pre-transplant MRI detected biliary, arterial, and venous variations in 42, 40, and 32 donors, respectively. Intra-operative cholangiograms were found to be discrepant with pre-operative MRIs in 35% of the cases. Furthermore, only 29 donors had acceptable image quality in all anatomical components. The mean estimated graft volume was 1015 ± 253 grams, while mean actual graft weight was 828 ± 204 grams. There was a linear correlation between the MRI-estimated graft weight and the actual graft weight (r: 0.83). Conclusion The utilization of pre-transplantation MRI in the evaluation of LLDs can provide valuable insights into anatomical variations. However, to avoid discrepancies between imaging and operative findings, it is important to exercise caution during graft volumetry and image interpretation. Furthermore, MRCP volumetry is another important step in ensuring that proper graft size is achieved.