Study of anatomical variations of hepatic vasculature using multidetector computed tomography angiography.

PURPOSE Preoperative evaluation of the hepatic vasculature is necessary to minimize mortality and morbidity during various surgeries due to the complexity of liver anatomy. The purpose of our investigation is to determine the anatomical variations in the hepatic vascular system by using multidetector computed tomography. METHODS In this observational study, 500 patients aged between 1 and 86 years were randomly chosen from a patient population referred for computed tomography angiography for various clinical indications. Multidetector computed tomography angiography examinations were performed using a 128 detector scanner. The area from the lower thoracic spine to symphysis pubis level, with the patient in a supine position, was adopted as the field of view. The percentage of occurrence of each of the vascular variant was determined. RESULTS Normal arterial anatomy [Type I] was seen in 306 patients [61.2%]. Replaced left hepatic artery from the left gastric artery was the most common variant in our study, which was seen in 57 patients [11.4%]. Classic hepatic venous anatomy was found in 261 [52.2%] patients. An accessory inferior right hepatic vein was found in 110 [22%] patients. A large early branch of segment VIII into middle hepatic vein was found in 157 patients [31.4%]. Extraparenchymal branching of the right anterior portal vein from the left portal vein was the most common anomaly found in 12 [2.4%] patients. CONCLUSIONS Computed tomography angiography can be used in preoperative evaluation in various hepatobiliary surgeries and interventional procedures, which give a lot of information regarding parenchyma and vascular system.