The hepatic interlobar fissure: combined in vitro and in vivo study.

A densely echogenic line is seen connecting the right portal vein and the neck of the gallbladder on longitudinal views in at least 70% of sonograms. The origin of the line has been taken to be the fissure between the right and left lobes of the liver, but no documentation has been provided. Intact liver specimens were studied in a water bath; metallic markers were placed to coincide with the line under real-time guidance. The line does, indeed, correspond to the interlobar fissure. Factors affecting visualization include position of the gallbladder neck and orientation of the fissure as well as fat deposition within the fissure.