SENSITIVITY OF DOUBLE-PHASE HELICAL CT DURING ARTERIAL PORTOGRAPHY FOR DETECTION OF HYPER-VASCULAR HEPATOCELLULAR-CARCINOMA

Purpose: The purpose of our work was to determine the usefulness of do uble-phase helical CT during arterial portography (CTAP) for the detec tion of hypervascular hepatocellular carcinoma (HCC). Method: Eighty-f our patients with 176 hypervascular HCC nodules underwent double-phase CTAP. Hypervascular HCCs were diagnosed by iodized oil CT after trans catheter arterial chemoembolization (TACE). The first-phase images wer e obtained 30 s after the initiation of injection of a nonionic iodina ted contrast medium into the superior mesenteric artery or splenic art ery, and the second-phase images were obtained after 70 s. These image s were interpreted separately for detection of HCC. Results: The doubl e-phase CTAP detected two nodules and six nodules that were missed by the first- and second-phase images, respectively. The sensitivity for hyper vascular HCC nodules was 89% for the first phase, 91% for the se cond phase, and 93% for the first phase and second phase combined. The double-phase CTAP showed significantly superior sensitivity to the fi rst-phase CTAP for detecting HCC nodules (p < 0.05). However, there wa s no statistically significant difference between the sensitivities of the double-phase CTAP and the second-phase CTAP. The positive predict ive Values of the double-phase images were inferior to those of either the first-phase or the second-phase images alone. Conclusion: Double- phase helical CTAP was found to be no better than second-phase CTAP al one for the detection of hypervascular HCC nodules.