Pre-operative hepatic vascular mapping of living donor for liver transplantation using 64-MDCT

Abstract

Objective

The purpose of the present study was to assess the performance of 64-row MDCT angiography in the mapping of hepatic vascular anatomy in potential living liver donors with special attention paid to the anatomical variants, which influence the donor selection and surgical planning.

Material and Methods

Evaluation of 43 potential living donors was performed using 64-row MDCT scanner to obtain hepatic arterial and venous phases. Eleven subjects were excluded as they did not perform the transplantation surgery. The hepatic arterial (HA) anatomy was evaluated and classified according to Michel classification with special attention given to those considered relative or absolute contraindications for donation and those may alternating the surgical procedure. The origin and course of the artery to segment IV were determined. Portal venous (PV) anatomy was assessed and classified according to Cheng classification. Hepatic venous anatomy was evaluated with special attention paid to middle hepatic vein (MHV) anatomy, significant accessory branches crossing dissection line or that may require additional anastomosis.

Results

64-Row MDCT was done for 43 potential living donors. Eleven subjects were excluded as they did not perform the transplantation surgery. Thirty-two living donors for liver transplantation were enrolled in this study. Standard hepatic arterial anatomy was determined in 19 subjects (59.4%) while 13 candidates (40.6%) showed hepatic arterial variations. The replaced RHA arises from the SMA was the commonest (n = 5, 15.6%). The dominant artery to segment IV was a branch from the left hepatic artery (LHA) in 24 cases (75%) and from right hepatic artery in 8 cases (25%). Classic portal venous anatomy was found in 26 candidates (81.2%) while its variants were detected in 6 cases. Standard hepatic venous anatomy was found in 21 candidates (65.6%). A total of 11 subjects (34.4%) showed hepatic venous variants. 8 cases (25%) had single significant accessory hepatic vein while 3 subjects (9.4%) had two or more significant accessory hepatic veins. MHV confluence was late in 4 candidates (12.5%). An accessory inferior right hepatic vein was the commonest accessory hepatic vein that was detected in 7 cases (21.9%).

Compared to surgical findings, MDCT correctly identified hepatic arterial and portal venous anatomy in all cases with no false positive or false negative cases. Sensitivity, specificity, PPV, NPV and accuracy of MDCT in identification of hepatic arterial and portal anatomy were all 100% while for hepatic venous anatomy, the corresponding values were 83.3%, 100%, 100%, 90.1% and 93.8%, respectively.

Conclusion

64-Row MDCT is an essential part of pre-operative evaluation of potential liver donors. It is a non-invasive comprehensive evaluation tool that can show the hepatic vascular anatomic details with precise relationship to liver parenchyma.