BACKGROUND: Multirow-detector helical CT (MDCT) allows faster Z-axis coverage and improves longitudinal resolution to scan the entire liver. This study was to evaluate the value of multiphase hepatic CT scans using MDCT in diagnosing hypervascular hepatocellular carcinoma (HCC).
METHODS: Multiphase hepatic CT scans in 40 patients were carried out with a Marconi Mx8000 MDCT scanner. The scans of early arterial phase (EAP), late arterial phase (LAP) and portal venous phase (PVP) were started at 21, 34 and 85 seconds after injection of contrast medium, respectively. The number of detected lesions was calculated in each phase. The density of the liver and tumor was greater than 1 cm for HCC, and the density of the liver and tumor in each phase was statistically calculated.
RESULTS: A total of 61 lesions were found in the 40 patients, and lesions greater than 1 cm were seen in 47 cases. The density differences between the liver and tumor were statistically significant (P<0.05) at the LAP and EAP and between the LAP, EAP and PVP. In the 61 lesions, the detectability in the EAP, LAP and the double arterial phases (DAP) was 32%, 87%, and 94%, respectively. Significant difference was found between the LAP plus PVP and the EAP plus PVP; but no significant difference was observed between the DAP plus PVP and the LAP plus PVP.
CONCLUSIONS: The utility of MDCT scan in the liver has optimized the protocol of arterial phase scan. MDCT is possible to scan the entire liver in a real arterial phase and it is very valuable in the detection of small HCC.