磁共振成像在结核性脓肾与肾积水鉴别诊断中的应用

Application of magnetic resonance imaging in differential diagnosis for tuberculous pyonephrosis and hydronephrosis

目的探讨几种磁共振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7例经手术病理证实的结核性脓肾及10例肾积水的磁共振图像特点,包括T1加权、T2加权、增强扫描、磁共振尿路成像及磁共振弥散加权成像。结果常规T1、T2加权可以了解肾脏的整体形态,提示肾实质破坏、积脓;增强扫描可以显示脓腔壁、肾盂、肾盏壁及输尿管壁的异常强化;磁共振尿路成像可以较清晰地显示两组病变的尿路整体形态;上述技术可使诊断正确率达84.7%。磁共振弥散加权成像既可以分析弥散图与ADC图了解水分子的弥散特点,也可以通过测量ADC值量化鉴别上述2种病变,与上述其他手段结合可使诊断正确率达91.2%。结论综合应用磁共振各项检查技术对结核性脓肾与肾积水的鉴别诊断有一定价值,可提高诊断正确率。

Objective To probe the value of varied magnetic resonance imaging （MRI） techniques applied in differential diagnosis of tuberculous pyonephrosis from hydronephrosis. Methods Features of MRI, including in T1WI with/without enhancement, T2WI, urology MRI and diffusion weighted image （DWI）, in seven cases with tuberculous pyonephrosis and 10 cases with hydronephrosis pathologically confirmed were retrospectively analyzed. Results Regular T1WI and T2WI could show morphology of the whole kidney, destruction of renal parenchyma and empyema. T1WI with enhancement could manifest abnormally reinforced walls of pyoid cavity, renal pelvis and calyx and ureter. Urology MRI could show morphology of the whole urinary passage with pathological changes more clearly. Accuracy of these techniques was 84. 7%. DWI had the advantage of analyzing diffusion image and ADC map to understand diffusion features of water molecule, and of quantitating ADC value to differentiate tuberculous pyonephrosis from hydronephrosis, with an accuracy of 91.2% combining with DWI and other methods. Conclusion Combined application of varied MRI techniques should be highlighted in differentiation of tuberculous pyonephrosis and hydronephrosis with a higher accuracy of diagnosis.