RESUMO
PURPOSE: The purpose of this study is to prospectively investigate the optimal dose of contrast medium for the depiction of hypervascular hepatocellular carcinoma (HCC) during the hepatic arterial phase (HAP), portal venous phase (PVP) and delayed phase (DP) of dynamic MDCT. MATERIALS AND METHODS: The study included 128 patients, out of these patients, 36 patients were found to have 56 hypervascular HCCs. Sixty-three patients were assigned to receive a dose of 525 mgI/kg with protocol A, and 62 received a dose of 630 mgI/kg with protocol B. Measurements of the attenuation values of the abdominal aorta, portal vein, hepatic vein, hepatic parenchyma and HCC during the HAP, PVP and DP were taken. Tumor-liver contrast (TLC) was calculated from the attenuation value of the hepatic parenchyma and HCC. RESULTS: The aortic attenuation value with protocol B (351, 166, and 132 HU) was significantly higher than that with protocol A (313, 153, and 120 HU) during all the phases, (P<0.01 for all phases). The hepatic enhancement from unenhanced baseline with protocol B (25.2, 63.6, 50.6 HU) was significantly higher than that with protocol A (20.2, 55.1 and 43.0 HU) during all the phases, (P<0.01 for all phases). The TLC with protocol B (37.4, -11.8 and -13.6 HU) was significantly higher than that with protocol A (28.0, -9.8 and -12.1 HU) during HAP (P=0.042). CONCLUSION: The administration of 630 mgI/kg of body weight depicts hypervascular HCC more clearly during HAP and shows sufficient hepatic enhancement of 50 HU during DP.
