Precision Preoperative Mapping of the Middle Hepatic Vein and Its Hidden Dangers: A Path to Safer Hepatobiliary...

This study aimed to characterize the relationship between the superficial branches of the middle hepatic vein (MHV) and the gallbladder bed. This was achieved by assessing their proximity, transverse diameter, and contact length using computed tomography (CT) and cadaveric studies. The goal was to identify anatomically high-risk venous configurations that may be vulnerable during cholecystectomy, based on combined imaging and cadaveric findings.

A retrospective analysis was performed on 473 potential liver donors who underwent multiphase CT angiography between August 2017 and January 2025. After exclusions, 457 patients were included, and 57 patients whose vascular structures were located within 1 mm of the gallbladder bed were selected for detailed evaluation. The measurements included the transverse diameter and longitudinal contact length of superficial venous branches adjacent to the gallbladder fossa, along with their segmental topography. To anatomically validate the radiological findings, 15 formalin-fixed cadavers were dissected. The differences in detectability between CT imaging and cadaveric dissection were also evaluated.

Superficial MHV branches were identified adjacent to the gallbladder bed in all selected patients, with a mean transverse diameter of 2.99 ± 1.06 mm and a mean contact length of 9.24 ± 4.41 mm. Most veins followed segment V-related trajectories (73.7%), whereas segment IV-related courses (26.3%) were less common, with no significant differences in morphometric measurements between the groups. Contact length was positively correlated with venous diameter. Portal vein variations were significantly associated with hepatic segmental anatomy (P = 0.025) but were not directly relevant to routine cholecystectomy. The cystic artery configuration was not significantly associated with sex (P = 0.442). Cadaveric dissection confirmed the MHV drainage patterns but also demonstrated that very small venous branches may fall below the detection threshold of CT imaging.

Superficial MHV branches frequently course in close proximity to the gallbladder bed. Preoperative imaging may enhance anatomical awareness and optimize the surgical plan. The proximity, contact length, and topographical patterns of these veins should be considered anatomical risk indicators rather than definitive predictors of vascular injury. These findings support the role of detailed preoperative imaging in improving surgical safety and anatomical comprehension.