The efficacy of contrast protocol in hepatic dynamic computed tomography: multicenter prospective study in community hospitals

PURPOSE To investigate four different contrast protocols to detect hypervascular hepatocellular carcinoma (HCC) most adaptable for patients at any body weight (BW) in clinical practice. MATERIALS AND METHODS A post-marketing surveillance of liver dynamic CT was prospectively performed by four different protocols in 415 patients: Protocol-A, BW-tailored dose of contrast media (CM: iohexol 300 mgI/mL), fixed injection duration (30s), fixed scan timing at arterial phase (AP); Protocol-B, BW-tailored dose of CM, fixed injection duration (30s), by bolus tracking; Protocol-C, BW-tailored dose of CM, fixed injection flow rate, by bolus tracking; Protocol-D, 100 mL constant of CM at any BW, fixed scan timing. Scan timing and tumor conspicuity at AP was scored qualitatively. The quantitative CT values of aorta and tumor liver contrast (TLC) were obtained. RESULTS The qualitative rate assessed "good" as scan timing of AP in Protocol-C was significantly lower than those in Protocols A and D (difference:16.6%, 17.4%, P = 0.0069, P = 0.0140, respectively). Scatter plot of Protocol-D (R(2) = 0.1283) at AP showed significant inverse relationship between TLC and BW (P =0.0053), although not significant in Protocols A, B, C. CONCLUSION In patients with higher BW, protocols of BW-tailored dose of CM and/or fixed injection duration have no dependence on BW to diagnose hypervascular HCCs.