Hepatic venous drainage: how much can we learn from imaging studies? Anatomic-functional classification derived from...

Area of Science:

• Hepatobiliary surgery
• Vascular anatomy
• Transplantation surgery

Background:

• Accurate knowledge of hepatic venous drainage patterns is critical for preventing severe venous congestion during live donor liver transplantation and extensive liver resections.
• Identifying "venous dominance" is key to surgical planning and patient safety in liver procedures.

Purpose of the Study:

• To present a novel anatomic-functional classification system for hepatic venous drainage.
• To delineate distinct patterns of venous dominance within the liver.

Main Methods:

• Utilized three-dimensional computed tomography (3D CT) reconstructions and virtual hepatectomies in 140 live liver donor candidates.
• Defined five distinct venous dominance types based on drainage volumes and territories.
• Identified and categorized "risky" venous configurations associated with potential congestion.

Main Results:

• The right hepatic vein (RHV) was the dominant vessel for the entire liver (TL) and the right hemiliver (RHH) in 83.5% of cases.
• The middle hepatic vein (MHV) was dominant for the TL in 15.5% and for the RHH in 27% of cases.
• A dominant RHV/IHV complex with significant IHV drainage, if unreconstructed, could lead to an MHV-dominant RHH (59.5% RHH).

Conclusions:

• The proposed anatomic-functional classification offers valuable insights into hepatic vein dominance.
• High-risk patterns for RHH venous congestion include a dominant MHV for the TL or a dominant RHV/IHV complex with large IHV drainage.