256层螺旋 CT 灌注成像区分轻、中度肝纤维化的价值

目的：探讨256层螺旋C T灌注成像区分轻、中度肝纤维化的价值。方法分析经肝穿刺活检证实轻度肝纤维化（F1期）患者18例和中度肝纤维化（F2、F3期）患者21例，均行256层螺旋CT肝脏灌注成像，采用体灌注软件获得肝动脉灌注（HAP），门静脉灌注（PVP），全肝总灌注（TLP）和达峰时间（TTP）参数值，对比分析2组灌注参数值差异，采用受试者工作特征曲线（ROC）评价各灌注指标区分轻、中度肝纤维化的能力，选择约登指数最大作为截断点，计算敏感度及特异度。结果中度肝纤维化患者与轻度肝纤维化患者相比，TTP明显增加（43．86±13．41） s vs （37．84±9．97） s ，P＝0．034）]，HAP、PVP及 TLP均无显著差异。ROC分析显示，TTP阈值在41．7 s区分轻、中度肝纤维化的敏感性为72．7％，特异性为75％。结论256层螺旋CT灌注参数能反映肝纤维化的血流动力学改变，TTP有助于区分轻、中度肝纤维化。

Differentiation of mild from moderate liver fibrosis with 256-slice CT perfusion imaging

Objective To assess the value of CT perfusion imaging in differentiation of mild from moderate liver fibrosis .Methods 18 patients with mild liver fibrosis (F1 phase) and 21 ones with moderate fibrosis (F2 and F3 phase) confirmed by liver biopsy were analyzed ,and all patients underwent the liver 256‐slice CT perfusion imaging .The differences in the CT parameters including hepatic arterial perfusion (HAP) ,portal venous perfusion (PVP) ,total liver perfusion (TLP) and time to peak (TTP) between dif‐ferent fibrosis were analyzed .ROC curve was used to evaluate the ability of perfusion indexes to distinguish mild from moderate liver fibrosis ,then the maximum Youden index was selected as a cutoff point to calculate the sensitivity and specificity .Results Compared with the mild fibrosis ,the TTP (43 .86 ± 13 .41)s vs (37 .84 ± 9 .97)s ,P=0 .034)] in liver with moderate fibrosis was significantly increased .However ,no differences in the HAP ,PVP and TLP were found .The ROC curve analysis showed that a TTP threshold of 41 .7 s allowed discrimination of mild from moderate fibrosis with a sensitivity of 72 .7% and a specificity of 75% .Conclusion 256‐slice CT perfusion imaging can reflect the hemodynamic changes of liver fibrosis ,and the TTP may help to discriminate mild from moderate fibrosis .