MRI与超声对肾外肾盂的诊断价值

The value of MRI and ultrasound in diagnosis of extrarenal pelvis

目的 探讨肾外肾盂的MRI和超声表现特点,比较两种检查方法对肾外肾盂的诊断价值.方法 搜集经静脉肾盂造影（IVP）证实肾外肾盂的68例患者,所有病例都同时行泌尿系MRI与彩色多普勒超声检查,对两种检查方法的诊断结果进行比较,分析肾外肾盂的MRI及超声表现特点,并比较两种检查方法对肾盂肾盂的诊断价值.结果 68例中,其中单侧54例,双侧14例,左侧38例,右侧44例;伴发同侧肾积水49例,肾外肾盂最大径线15～82mm,平均42.3mm; MRI诊断61例,误诊7例,其中5例误诊为肾盂旁囊肿,肾盂积水2例;超声诊断48例,误诊20例,其中7例误诊为肾盂旁囊肿,肾盂积水13例.MRI及超声对肾外肾盂的诊断具有统计学差异（x2=7.81,P=0.005）.肾外肾盂在MRI横断位及冠状位图像表现为肾窦外长T1长T2水样信号,并且与正常肾盂相通.超声表现为肾门外与肾盂相延续囊状液暗区,内部回声均匀,未见正常肾实质包绕,肾外形及肾实质无改变.结论 MRI及超声均是诊断肾外肾盂的重要无创性检查方法,MRI可以多平面显示肾外肾盂与肾脏的位置关系,对肾外肾盂的诊断优于超声检查.

Objective To evaulate the imaging features of MRI and ultrasound in diagnosis of extrarenal pelvis, and to compare the diagnostic value of the two methods of extrarenal pelvis. Methods 68 cases of extrarenal pelvis confirmed by intravenous urography angiography （IVP） were collected in the study, all cases underwent urinary MRI and color doppler ultrasonography. We compared the results of the two methods, analyzed the imaging characteristics of MRI and ehocardio- graphy（UCG）, and compared the diagnostic value of the two methods of extrarenal pelvis. Results In68 cases,there were 54 cases of unilateral side, 14 cases of bilateral side, 38 cases of the left side, 44 cases of right side, and 49 cases associated with ipsilateral hydronephrosis. The maximum diameters were 15-82 mm, with an arerage of 42.3 mm. MRI diagnosed 61 cases, 7 cases were misdiagnosed, including 5 cases misdiagnosed as parapelvic cyst and 2 cases misdiagnosed as hydronephrosis. Ultrasound diagnosed 48 cases, 20 cases were misdiagnosed, including 7 cases misdiagnosed as parapelvic cyst and 13 cases misdiagnosed as hydronephrosis. There were statistically significant differences between MRI and ultra- sound in diagnosis of extrarenal pelvis （X^2 =7.81, P ：0. 005）. Extrarenal pelvis in the transverse and coronal MRI images showed long T1 long T2 watery signals, and communicated with normal renal pelvis. Ultrasound showed Outside the Renal hilum could seen a liquid dark area interlinked with the pelvis, internal echo uniform, no normal renal parenchyma, no change of renal kidney shape and renal parenchyma. Conclusion MRI and ultrasound are both the important noninvasive methods in diagnosis of extrarenal pelvis. MRI can display the positional relationship between： renal pelvis and kidney in mlti-plane and is better than ultrasound in diagnosis of extrarenal pelvis.