肾脏肿瘤的MR动态增强扫描研究

目的:探讨MR动态增强扫描在肾脏肿瘤诊断和鉴别诊断中的价值。方法:对21例肾细胞癌、11例肾错构瘤和6例肾囊肿行MR常规检查及动态增强和延迟增强扫描,测量病灶的信号强度,绘制时间-对比增强率曲线并对动态增强的类型及血液动力学改变进行分析。结果:肾脏肿瘤动态增强后的时间-对比增强率曲线不同,富血供肾癌在早期强化并逐渐上升,但其时间-对比增强率曲线无明显峰值;乏血供肾癌早期轻度强化,缓慢上升至60s后趋于稳定;肾错构瘤早期即明显强化,于30s达到强化高峰后快速下降;肾囊肿则无明显强化。结论:通过定量分析肾脏肿瘤的信号强度,动态增强MRI可以提供肿瘤的血供信息,有助于肾脏肿瘤的诊断和鉴别诊断。

Study of dynamic contrast-enhanced MR imaging in renal tumour

Objective:To determine the characteristics of dynamic contrast-enhanced MRI(DCE-MRI) of the lesions in 38 cases with renal disease in order to improve the diagnosis and differentiation ability of MRI in kidney neoplasm.Methods:Conventional plain scans,dynamic and delay enhanced scans were performed in 21 cases with renal carcinoma,11 cases with renal angiomyolipoma and 6 cases with renal cyst.The signal intensity of the lesions,the normal renal cortex and medulla were measured and the curves of time-contrast enhancement ratio were drawn in dynamic MRI.At the same time,the hemodynamics and the patterns of enhancement were analyzed respectively.Results:The findings of rapid dynamic contrast enhancement and the curve of time-contrast enhancement ratio of various kidney lesions were different.Hypervascular renal carcinomas were enhanced obviously in early phase and the enhancement was strengthened gradually.But there was no obvious peak on the curve of time-contrast enhancement ratio.Hypovascular renal carcinomas were enhanced slightly in early phase and the enhancement increased slowly and became stable 60 s after contrast agent injection.The lesions of angiomyolipomas were enhanced obviously in early phase and the enhancement began to decrease after reaching the peak 30 s after contrast agent injection.Renal cysts had no enhancement.Conclusion:By quantitative analysis of MRI signal intensity,DCE-MRI can provide the hemodynamics information of tumors and is useful in the diagnosis and differentiation of renal diseases.