磁共振扩散加权成像在肾盂积水及结核性脓肾鉴别中的应用

Diffusion-weighted MR imaging in differentiating tuberculous pyonephrosis from hydronephrosis

目的探讨磁共振扩散加权成像技术在结核性脓肾与肾积水鉴别诊断中的价值。方法回顾性分析了经手术病理证实的7例结核性脓肾及10例肾积水病人的磁共振扩散加权成像(DWI)的图像特点。结果首先利用扩散加权图像拟合出表观扩散系数(ADC)图,随后对肾脏集合系统进行ADC的测量。在扩散图中肾盂积水病人肾盂内信号的强度低于结核性脓肾,而结核性脓肾肾盂内所测的ADC低于肾盂积水。结论磁共振扩散加权成像是一种可信度较高且无创的结核性脓肾与肾积水的鉴别诊断方法。

Objective To investigate the value of diffusion-weighted MR imaging in differentiating tuberculous pyonephrosis from hydronephrosis. Methods The diffusion weighted images of tuberculous pyonephrosis （7 cases） and hydronephrosis （10 cases） confirmed by histopathology were analyzed retrospectively. Results Apparent diffusion coefficient （ADC） maps were produced from the diffusion-weighted images, the ADC values of the pelvicalyceal system in all patients were computed and compared by t test. On diffusion-weighted images, the pelvicalyceal system of hydronephrosis was hypointense while that of tuberculous pyonephrosis was markedly hyperintense. The mean ADC values of tuberculous pyonephrosis in renal pelvis were lower than that of hydronephrosis. Conclusion Diffusion-weighted MR imaging may be a reliable and noninvasire tool to differentiate tuberculous pyonephrosis from hydronephrosis.