ANALYSIS OF CT IMAGE OF THE PORTA HEPATIS WITH CORRELATION TO ANATOMICAL STRUCTURES

Abstract

Fourteen liver specimens and 940 consecutive CT scans of the liver were studied to analyze the basic anatomical structures which constitute the CT image of the porta hepatis. Each unfixed liver was set in its original shape as it had been in the abdominal cavity, and then was sliced at 10mm intervals through the body's transverse section, and thus CT-macroscopic comparison became possible. Inspection of the cut surface revealed that the porta hepatis was an area of adipose tissue with four recesses radiating into the surrounding liver parenchyma, and this contour had a good correspondence to that of the low density area of the porta hepatis with four fissures around it on CT scans. Three of the four fissures were due to the sulci for lig, falciform, lig. venosum and liver bed on the visceral surface of the liver. The remaining one was due to a cone-shaped adipose tissue entering into the liver parenchyma as a cuff of the right lobar branches of portal vein, hepatic artery and bile duct. On CT scans, pars transversus and pars umbilicus of the left lobar branch of the portal vein appear in the low density area of the porta hepatis just one slice cephalad to that in which the right lobar branch appears.