VARIATIONS IN THE INTRAHEPATIC PORTIONS OF THE HEPATIC AND PORTAL VEINS - FINDINGS ON HELICAL CT SCANS DURING ARTERIAL PORTOGRAPHY

OBJECTIVE. The goals of this study were to describe variations in the intrahepatic portions of the hepatic and portal veins as visualized by helical CT during arterial portography (CTAP) and to examine the surg ical implications of these findings. MATERIALS AND METHODS. A retrospe ctive review of 69 helical CTAP scans of 69 patients with small hepati c tumors and no evidence of vascular invasion or distortion was done. Axial helical CTAP scans were reviewed to determine the presence, numb er, and location of intrahepatic portions of the hepatic and portal ve ins. RESULTS. Among the 60 patients (87%) in whom the right, middle, a nd left hepatic veins were visualized, 19 (32%) had supernumerary hepa tic veins. Right inferior hepatic veins were found in six (9%) of the 69 patients. Variations in intrahepatic portal anatomy were found in f our patients (6%) and involved an immediate trifurcation of the portal vein in three patients (4%) and a left main portal vein originating f rom the right anterior portal branch in one patient (2%). CONCLUSION. Variations in the intrahepatic portions of the hepatic and portal vein s are frequently seen on helical CTAP scans. Recognition of such varia tions is important in the preoperative evaluation of patients with hep atic tumors because these variations may have implications for tumor r esection and for planning the operative approach.