Liver

Couinaud’s functional segmental anatomy.

 

A, The liver is divided into nine segments. Blue longitudinal boundaries (right, middle, and left scissurae) are three hepatic veins. Transverse plane is defined by right main and left main portal pedicles.

egment I, caudate lobe, is situated posteriorly. RHV, Right hepatic vein; MHV, middle hepatic vein; LHV, left hepatic vein; RPV, right portal vein; LPV, left portal vein; GB, gallbladder.

B, Corresponding sonogram shows the main portal vein with its right and left branches. The plane through the right and left branches is the transverse separation of the liver segments. Cephalad to this level lie segments II, IVa, VII, and VIII. Caudally located are segments III, IVb, V, and VI.