双期增强螺旋CT扫描对于鉴别肾微脂肪成分血管平滑肌脂肪瘤与肾癌的典型特征研究

TYPICAL FEATURES IN DIFFERENTIATING ANGIOMYOLIPOMA WITH MINIMAL FAT FROM RENAL CELL CARCINOMA AT BIPHASIC HELICAL CT

目的发现能够鉴别肾微脂肪成分血管平滑肌脂肪瘤及肾癌的典型CT特征。方法本组包括15例肾微脂肪成分血管平滑肌脂肪瘤及50例肾癌患者。所有患者均行螺旋CT双期增强扫描(平扫,皮髓质期及分泌早期)。分析常见的CT特征,包括平扫时的密度,增强时的特征(如是否均质强化,强化时的CT值,强化的时效特性),肿瘤边缘,肿瘤中心的位置,瘤内钙化。结果均质强化和延时强化是肾微脂肪成分血管平滑肌脂肪瘤的典型CT特征,对于二者的鉴别有重要价值。结论双期增强螺旋CT对于鉴别肾微脂肪成分血管平滑肌脂肪瘤及肾癌有重要价值,均质强化及延时强化是提示微脂肪成分血管平滑肌脂肪瘤的有价值的特征。

Objective To find out computed tomography（CT） typical features in differentiating angiomyolipoma （AML） with minimal fat from those of size matched renal cell carcinoma（RCC）. Methods 15 patients with AML with minimal fat and 50 patients with RCC were included in the study. All of them had undergone biphasic CT（CT scan with unenhanced , corticomedullary and early excretory phase scanning ）. All the CT features, including tumor attenuation on unenhanced CT scans, enhancement characteristics （ie, homogeneity of enhancement ,CT value of enhancement, enhancement pattern oven time）, tumor margin,location of tumor center, intratumoral calcification were evaluated. The x^2 test was used to compare the data of AML with minimal fat and RCC. Results Homogeneous enhancement （80% of AMLs VS 4% of RCCs） and prolonged enhancement pattern （ 60% of AMLs VS 10% of RCCs ）, both were valuable for differentiating AML with minimal fat from RCC （P〈0. 05 for both ）. Conclusion Biphasic helical CT is useful in differentiating AML with minimal fat from RCC. Homogeneous enhancement and prolonged enhancement pattern are the most valuable CT findings to suggest AML with minimal fat.