OBJECTIVE To determine whether the addition of computed tomographic (CT) angiography to CT arterial portography would improve lesion detection and heighten confidence in interpreting perfusion abnormalities. METHODS The two examinations were performed sequentially in 10 candidates for surgical resection of hepatic tumors. Arterial vascular access was obtained with bilateral punctures of the common femoral artery and selective placement of angiographic catheters in the hepatic artery and superior mesenteric artery (SMA). CT scans were obtained first during injection of contrast material into the SMA, followed by repeated imaging of the liver during injection of contrast material into the hepatic artery. RESULTS The procedure demonstrated, among other results, three additional lesions in two patients, a possibly nontumorous abnormality as tumorous in one, and a suspected tumorous abnormality as nontumorous in one. Suspected nontumorous abnormalities in four patients were confirmed at CT angiography. CONCLUSIONS These preliminary data support a trial of this technique in a larger population.