肾乏脂性血管平滑肌脂肪瘤在MSCT腹部常规双期增强扫描中的强化特征分析

Enhancement characteristics of renal angiomyolipoma with minimal fat on routine biphasic abdominal MSCT

目的 :研究肾乏脂性血管平滑肌脂肪瘤(Angiomyolipoma with minimal fat,AMLmf)在MSCT腹部常规双期增强扫描中的强化特征。材料和方法:回顾性分析2007年2月—2013年4月经手术病理证实的15例肾AMLmf在腹部常规双期增强扫描中的CT表现,计算并比较AMLmf病灶实质和正常肾皮质在平扫、动脉期、静脉期的CT值,病灶在动静脉期的强化程度以及病灶实质与肾皮质的强化比值。结果:肾AMLmf肿块在平扫时密度高于正常肾实质,但两者差异无统计学意义(P=0.068);动脉期和静脉期,肿块较明显强化,但增强后的CT值显著低于正常肾皮质(P=0.014,0.001);肿块在动静脉期与平扫比较后的强化值,以及与正常肾皮质的强化比值未见显著差异(P>0.05);AMLmf在动静脉期的强化模式呈"平台型",而肾实质呈"渐升型"。结论:肾AMLmf在腹部常规双期增强扫描动脉期明显强化,静脉期强化程度与动脉期相似,动静脉期强化值均显著低于肾皮质,呈"平台型"强化模式。

Objective： To investigate enhancement characteristics of renal angiomyolipoma with minimal fat （AMLmf） on routine biphasic abdominal MSCT. Methods： Fifteen cases of AMLmf were reviewed retrospectively which confirmed by pathol- ogy from February 2007 to April 2013. The CT features of AMLmf were analyzed, and the CT value of lesions and normal nephric cortex in pre-contrasted CT scan, arterial phase, and venous phase were calculated and compared. Enhancement de- gree of lesions and enhancement ratio between lesions and nephric cortex in arterial phase, venous phase were calculated and compared in our study. Results： The attenuation of the mass was higher than normal nephric parenchymal in plain scan, how- ever, there was no significant difference between them （P=0.068）. In arterial phase and venous phase, the enhancement of le- sion was avid, but the CT values of mass were lower than nephric cortex significantly （P value was 0.014, 0.001）. There were no significant difference in enhancement degree of lesion and enhancement ratio between lesion and nephric cortex in both arterial phase and venous phase （P〉0.05）. The enhancement model of AMLmf at biphasic MSCT was plateau curve, and the nephric parenchymal was persistent enhancement type. Conclusions： The enhancement of AMLmf on biphasic abdominal MSCT was avid and the enhancement degree of lesion was similar in both arterial and venous phase, the enhancement of lesion was significant lower than nephric cortex. The enhancement model of AMLmf on biphasic abdominal MSCT was plateau curve.