Anomalous arterial ramification in the right liver.

PURPOSE: The aim of this study was to investigate whether individual arterial and portal venous division during hepatectomy is always safe by examining the presence of the anomalous arterial ramification in the right liver.

METHODS: The ramifications of the right hepatic artery (RHA) were investigated by three-dimensional (3D) reconstruction imaging using a computer software program in 87 patients undergoing computed tomography during angiography as a preoperative assessment of intrahepatic tumors.

RESULTS: The anterior view showed that the RHA bifurcated into the anterior and posterior sector arteries at the hilum in 76 patients. Sector-intersecting arteries from the posterior to the anterior sector and vice versa were found in 7 and 4 of those patients, respectively. The RHA in the other 11 patients was divided in a complex manner into more than 2 arteries: e.g., the first branch to the cranial part of the posterior sector, the second to the anterior sector, and the third to the caudal part of the posterior sector. A total of 22 patients showed anomalous ramification of RHA.

CONCLUSION: Preoperative observation of the hepatic artery by 3D imaging is very useful to detect anomalous ramification. Arterial dissection during the intrafascial approach should be cautiously performed based on the 3D images.