摘要
AIM:To evaluate the feasibility of intravenous contrast-enhanced C-arm computed tomography (CT) for assessing ablative areas and margins of liver tumors. METHODS: Twelve patients (5 men, 7 women; mean age, 69.5 years) who had liver tumors (8 hepatocellular carcinomas, 4 metastatic liver tumors; mean size, 16.3 mm; size range, 8-20 mm) and who underwent percutaneous radiofrequency ablations (RFAs) with a flat-detector C-arm system were retrospectively reviewed. Intravenously enhanced C-arm CT and multidetector computed tomography (MDCT) images were obtained at the end of the RFA sessions and 3-7 d after RFA to evaluate the ablative areas and margins. The ablated areas and margins were measured using axial plane images acquired by both imaging techniques, with prior contrast-enhanced MDCT images as the reference. The sensitivity, specificity, and positive and negative predictive values of C-arm CT for detecting insufficient ablative margins (< 5 mm) were calculated. Statistical differences in the ablative areas and margins evaluated with both imaging techniques were compared using a paired t-test. RESULTS: All RFA procedures were technically successful. Of 48 total ablative margins, 19 (39.6%) and 20 (41.6%) margins were found to be insufficient with C-arm CT and MDCT, respectively. Moreover, there were no significant differences between these 2 imaging techniques in the detection of these insufficient ablative margins. The sensitivity, specificity, and positive and negative predictive values for detecting insufficient margins by C-arm CT were 90.0%, 96.4%, 94.7% and 93.1%, respectively. The mean estimated ablative areas calculated from C-arm CT (462.5 ± 202.1 mm2) and from MDCT (441.2 ± 212.5 mm2) were not significantly different. The mean ablative margins evaluated by C-arm CT (6.4 ± 2.2 mm) and by MDCT (6.0 ± 2.4 mm) were also not significantly different. CONCLUSION: The efficacy of intravenous contrast-enhanced C-arm CT in assessing the ablative areas and margins after RFA of liver tumors is nearly equivalent to that of MDCT.
AIM:To evaluate the feasibility of intravenous contrastenhanced C-arm computed tomography(CT) for assessing ablative areas and margins of liver tumors.METHODS:Twelve patients(5 men,7 women;mean age,69.5 years) who had liver tumors(8 hepatocellular carcinomas,4 metastatic liver tumors;mean size,16.3 mm;size range,8-20 mm) and who underwent percutaneous radiofrequency ablations(RFAs) with a flatdetector C-arm system were retrospectively reviewed.Intravenously enhanced C-arm CT and multidetector computed tomography(MDCT) images were obtained at the end of the RFA sessions and 3-7 d after RFA to evaluate the ablative areas and margins.The ablated areas and margins were measured using axial plane images acquired by both imaging techniques,with prior contrast-enhanced MDCT images as the reference.The sensitivity,specificity,and positive and negative predictive values of C-arm CT for detecting insufficient ablative margins(< 5 mm) were calculated.Statistical differences in the ablative areas and margins evaluated with both imaging techniques were compared using a paired t-test.RESULTS:All RFA procedures were technically successful.Of 48 total ablative margins,19(39.6%) and 20(41.6%) margins were found to be insufficient with C-arm CT and MDCT,respectively.Moreover,there were no significant differences between these 2 imaging techniques in the detection of these insufficient ablative margins.The sensitivity,specificity,and positive and negative predictive values for detecting insufficient margins by C-arm CT were 90.0%,96.4%,94.7% and 93.1%,respectively.The mean estimated ablative areas calculated from C-arm CT(462.5 ± 202.1 mm 2) and from MDCT(441.2 ± 212.5 mm 2) were not significantly different.The mean ablative margins evaluated by C-arm CT(6.4 ± 2.2 mm) and by MDCT(6.0 ± 2.4 mm) were also not significantly different.CONCLUSION:The efficacy of intravenous contrastenhanced C-arm CT in assessing the ablative areas and margins after RFA of liver tumors is nearly equivalent to that of MDCT.
