低剂量MSCTU在输尿管阴性结石诊断中的价值

Value of low-dose MSCTU in diagnosis of ureteral radiolucent calculi

目的探讨低剂量多层螺旋CT尿路造影(MSCTU)在输尿管阴性结石诊断中的价值。方法回顾性分析42例经输尿管镜或手术证实的输尿管结石患者的影像学资料。所有病例均为临床高度怀疑输尿管结石,而所做影像学检查均未能确诊,最后进行低剂量MSCTU检查。所有病例均进行B超及泌尿系平片(KUB)检查,其中,8例行静脉尿路造影(IVP),11例行多层螺旋CT(MSCT)平扫。所有病例的MSCT平扫及MSCTU薄层数据分别传至后处理工作站进行分析。结果本组MSCTU的CT剂量指数(CTDI_(vol))为4.89mGy,辐射剂量长度乘积(DLP)为(191.16±13.96)mGy·cm。MSCT平扫明确诊断输尿管结石23例(直径4～15 mm),可疑输尿管结石14例(直径3～6mm),输尿管全程未见明确结石(阴性)5例。低剂量MSCTU明确诊断输尿管结石32例(直径3～14 mm),可疑输尿管结石6例(直径3～12 mm),阴性4例。结合低剂量MSCT平扫及MSCTU,明确诊断输尿管结石39例(直径3～14mm),与输尿管镜或手术所见一致;可疑输尿管结石2例;阴性1例。结论低剂量MSCTU在输尿管阴性结石诊断中有重要价值,但必需与低剂量MSCT平扫联合应用。

Objective To explore the value of low-dose multi-slice spiral CT urinary imaging in diagnosis of ureteral radiolucent calculi. Methods 42 cases with ureteral radiolucent calculi proved by ureteroscopy or surgery were analyzed retrospectively. All cases were high suspicion of ureteral calculi in clinical with negative X-ray. All cases underwent low-close MSCTU, uhrasonography and KUB. 8 of them got intravenous urography （IVP） and 11 of them got MSCT scanning. All MSCT images were analyzed with the post-processing workstation. Results The average CT dose index （CTDIvol） were 4.98 mGy, and the dose length product （DLP） of the MSCTU were 191.16±13.96）mGy.cm. By non-enhanced MSCT,23 cases were diagnosed ureteral calculi （diameter 4-15 ram）, 14 were suspicious of ureteral calculi （diameter 3-6 mm） and 5 cases were negative. By low-MSCTU, 32 ureteral calculi diagnosed definitely （diameter 3-14 mm）, 6 suspected （diameter 3-12 mm） and 4 negative. Combining with the two methods, 39 ureteral calculi were diagnosed definitely （diameter 3-14 mm） in accordance with ureteroscopy and surgery, 2 were suspected and 1 was negative. Conclusion Low-dose MSCTU plays an important part in diagnosis of ureteral radiolueent calculi, and it should be combined with low-dose non-enhanced MSCT.