目的 旨在探讨多层螺旋CT低剂 量平扫在诊断肾及输尿管结石中的应用价 值。方法 选取我院2017年1月-2018年6月 我院收治的肾及输尿管结石患者69例，患 者均进行了低剂量扫描及常规CT平扫检 查，观察69例患者结石的有无、大小、位 置、数目等相关情况，计算低剂量扫描 检查诊断肾及输尿管结石的敏感度、特 异度，并比较两种扫描方式辐射剂量水 平。结果 常规CT扫描检查结果显示，肾 结石患者41例，共63个结石，输尿管结石 28例，共38个；结石直径：54个结石直径 <0.5cm，23个结石直径0.5-1.0cm，24个 结石直径>1.0cm。低剂量CT检查共检出 98个结石，其中52个结石直径<0.5cm， 22个结石直径0.5-1.0cm，24个结石直径 >1.0cm。常规CT扫描检出不同直径肾及输 尿管结石数量与低剂量CT扫描比较，差 异无统计学意义(χ2 =3.045，P=0.081)。 低剂量CT扫描检查诊断肾结石的敏感 度、特异度分别为93.65%(59/63)、 92.06%(58/63)，检查诊断输尿管结石的 敏感度、特异度分别为92.10%(35/38)、 94.73%(36/38)。常规CT平扫辐射剂量为 (10.25±2.41)mGy·cm，明显高于低剂量 CT(3.61±1.01)mGy·cm，差异具有统计 学意义(P<0.001)。结论 多层螺旋CT低剂 量平扫对肾及输尿管结石检出率、敏感度 及特异度高，能有效降低辐射剂量，值得 临床推广。

Objective To explore the application value of low dose multi-slice spiral CT (MSCT) in the diagnosis of renal and ureteral calculi. Methods 69 patients with renal and ureteral calculi admitted to our hospital from January 2017 to June 2018 were selected. All the patients underwent low-dose scanning and routine CT non-enhanced scanning The presence, size, location and number of calculi in 69 patients were observed, the sensitivity and specificity of kidney and ureteral calculi diagnosed by low-dose scanning were calculated, and the radiation dose levels of the two scanning methods were compared. Results The results of routine CT scan showed that there were 41 cases of renal calculi, a total of 63 calculi, and 28 cases of ureteral calculi, a total of 38. Stone diameter: 54 stones diameter <0.5cm, 23 stones diameter 0.5-1.0cm, 24 stones diameter >1.0cm. A total of 98 stones were detected by low-dose CT examination, of which 52 stones were <0.5cm in diameter, 22 stones were 0.5-1.0cm in diameter, and 24 stones were >1.0cm in diameter. Compared with the low-dose CT scan, the number of kidney and ureteral calculi with different diameters was not statistically significant (χ2=3.045, P=0.081). The sensitivity and specificity of low-dose CT scanning in the diagnosis of renal calculi were 93.65% (59/63), 92.06% (58/63), and the sensitivity and specificity of the diagnosis of ureteral calculi were 92.10% (35/38) and 94.73% (36/38), respectively. The radiation dose of conventional CT non-enhanced scan was (10.25±2.41) mGy·cm, significantly higher than that of low-dose CT (3.61±1.01), and the difference had statistical significance (P<0.001). Conclusion Multi-slice spiral CT with low dose has high detection rate, sensitivity and specificity for renal and ureteral calculi, which can effectively reduce radiation dose and is worthy of clinical promotion.