The proximity of the middle hepatic vein to the hepatic hilus: a retrospective radiological study.

Abstract

The middle hepatic vein (MHV) is an important landmark in anatomical hemihepatectomy. The proximity between the MHV and the hilar plate was suspected to be associated with tumor exposure during left hemihepatectomy for advanced perihilar cholangiocarcinoma and is reported to facilitate a dorsal approach to the MHV during laparoscopic hemihepatectomy. However, the precise distance between these locations is unknown. To investigate the "accurate and normal" distance between the MHV and the hilar plate, the present study focused on patients who presented without perihilar tumor. One hundred and sixty-eight consecutive patients who underwent pancreatoduodenectomy were included. Retrospective radiological measurement was performed using preoperative multi-detector row CT. The optimized CT slices perpendicular to the MHV were made using the multiplanar reconstruction technique. The shortest distance between the MHV and the hilar plate was measured on the left and right sides on the perpendicular slices. The diameters of the left and right hepatic ducts were also measured. The distance was 9.0mm (1.9-20.0mm) on the left side and 11.3mm (2.3-21.8) on the right side (p < 0.001). The distance on the left side was < 10mm in 60% of patients (n = 100). Only one-third of patients (n = 55) had a distance of ≥ 10mm on both sides. As the hepatic ducts became more dilated, the distance from the MHV to the hilar plate became shorter. The MHV was located in close proximity to the hepatic hilus, especially on the left side.