Spiral biphasic contrast-enhanced computerized tomography in the diagnosis of hepatocellular carcinoma

Advances in spiral computerized tomography (CT) have made rapid biphasic contrst-enhanced CT possible. This study evaluated the capability of biphasic contrast-enhanced spiral CT to detect hepatocellular carcinoma (HCC). A total of 125 patients (68 men and 57 women) with proven HCC underwent preliminary noncontrast (NC) scanning, followed by hepatic arterial phase (HAP) and portal venous phase (PVP) imaging. Contrast medium (80 mL, 300 mgI/mL) was administered routinely at a rate of 2 mL/second using an automated contrast injector under guidance software monitoring. Study of NC and PVP images without concurrent study of HAP images detected 131/171 (76.6%) cases of HCC. In contrast, combined study of NC, PVP, and HAP images detected 153/171 (89.5%) cases of HCC. Thus, combined study of NC and biphasic images was able to detect an additional 12.9% of HCC cases in comparison with conventional study of NC and PVP images only. All HCCs that were detectable only on HAP imaging were enhanced homogeneously with contrast medium during the arterial phase.