Detection of hepatocellular carcinoma on CT in liver transplant candidates: comparison of PACS tile and multisynchronized stack modes

Abstract

OBJECTIVE: The objective of our study was to compare CT image interpretation using PACS tile and multisynchronized stack modes with respect to speed and observer performance for the detection of hepatocellular carcinoma (HCC) in liver transplant candidates. MATERIALS AND METHODS: Institutional review board approval was obtained, but informed consent was not required for this retrospective study. Sixty-seven patients underwent dynamic multiphasic CT within 3 months before liver transplantation. Interval reviews using tile and multisynchronized stack modes were performed independently by four reviewers with various levels of experience to determine the presence of HCC using a five-point confidence scale. Observer performance was compared using jackknife free-response receiver operating characteristic (ROC) analysis. The time required to interpret the CT scans using each mode was recorded and compared using the paired Student's t test. RESULTS: Twenty-seven patients had 48 HCC nodules. The mean free-response ROC figures of merit for detecting HCC were significantly higher using the multisynchronized stack mode (0.731) than using the tile mode (0.662) (F-statistic = 6.603, p = 0.012). The 95% CIs for the task were -0.125 - -0.016. The time used for image analysis was also significantly shorter with the stack mode (63 to approximately 75 seconds) than with the tile mode (94 to approximately 191 seconds) for all four reviewers (p < 0.0001). CONCLUSION: Multisynchronized stack viewing of multiphasic dynamic CT scans significantly increases the detection rate of HCC in liver transplant candidates. It also significantly shortens the interpretation time compared with tile viewing.