磁共振尿路成像对尿路梗阻的诊断价值

The Value of MR Urography in Diagnosis of Urinary Tract Obstruction

目的：评价磁共振尿路成像（MRU）对尿路梗阻的诊断价值。材料与方法；在PHILIPSGYROSCANT10－NT1．0T超导型磁共振成像仪上用重度T2加权（TR／TE＝2000／700ms）涡流自旋回波（TSE）序列对13名病人的14例尿路梗阻病变（先天性肾盂输尿管交界处狭窄4例、输尿管炎性或手术后狭窄4例、输尿管结石3例、输尿管癌1例、腹腔肿瘤侵犯输尿管1例及先天性输尿管膀胱连接区梗阻1例）作MRU检查，同时采用呼吸触发和脂肪抑制技术。图像后处理以最大强度投射法（MIP）进行三维（3D）重建。结果：14例尿路梗阻病变的MRU检查成功率为100％，MRU对尿路积水程度的判断和尿路梗阻的定位诊断准确性为100％，MRU对尿路梗阻的定性诊断符合率为85．7％。结论：MRU检查具有无创伤性、不需造影剂和不受肾功能异常的影响等诸多优势，为泌尿系疾病的影像学诊断开辟了一条新的途径。MRU对尿路梗阻的定位和定性诊断准确性高，尤其是在静脉尿路造影（IVU）等其它检查有禁忌症或诊断不明确时，可以作为一种理想的替代检查方法。

To evaluate the value of Magnetic Resonance Urography(MRU) in diagnosis of urinary tract obstruc-tion. Materials and Methods: On a PHILIPS GYROSCAN T10-NT 1.0T superconductive MR imaging unit, MRU was per-formed in thirteen patients with fourteen urinary obstructive diseases, using heavily T2-weighted Turbo Spin-Echo (TSE) pulse sequence, respiratory-triggering and fat-suppression techniques, including 4 cases of congenital stricture in ureteropyelic junc-tion, 4 cases of ureteral inflammation or postsurgical stricture, 3 cases of ureterolith, 1 case of ureteral carcinoma, 1 case of ab-dominal mass invading ureter, and 1 case of congenital ureterovesical junction obstruction. Three-dimensional (3D)reconstruction was used for postprocedure processing with a maximum-intensity projection (MIP) algorithm. Results: MRU examination was succeeded technically in all 14 urinary tract obstruction cases (100%) and MR utograms were shown satisfactorily. The accuracy of MRU in the detection of urinary tract dilatation and the localization of the level of obstruction was 100%. The accuracy of MRU for evaluating the cause of obstrucsion was 85.7%. Conclutioh: MRU is a noninvasive method, independent of excretory function of kidney and no contrast agent is required. It blazes a trail for revealing urinary tract disorders with image technique. Be-cause of the excellent accuracy in the diagnosis of urinary tract obstruction and its cause,MRU may provide an effcient alternative examination to intravenous urography (IVU), especially when IVU and other studies are contraindicated or inconclusive.