低剂量MSCT尿路造影对正常输尿管图像质量影响的研究

The study of the effect on the image quality for normal ureter with low-dose multi-slice spiral CT urography

目的探讨多层螺旋CT尿路造影(MSCTU)扫描时,单纯降低mA值患者受到的辐射剂量是否有效减少,以及在低剂量条件下对正常输尿管显示的图像质量有无影响。方法根据螺旋CT扫描时管电流的设置,将38例患者中的72侧正常输尿管分为标准mA组和低mA组,分别测量辐射剂量值、采用评分法观察图像质量,并进行统计学检验。结果单纯将管电流由标准mA降至低mA时,患者所接受的平均辐射剂量由15.19mGy降至5.66mGy(P<0.05),而MSCTU图像质量无明显下降(P>0.05)。结论单纯降低管电流,能在保证正常输尿管MSCTU图像质量的前提下,有效降低辐射剂量。

Objective To determine the effect of reducing mA on the radiation close and image quality of normal ureter in patients undergoing the multi-slice spiral CT urography. Methods 72-sides of normal ureters in 38 patients were divided into standard-dose and low-dose groups according to the fixed kv set. The radiation close was measured and image quality was evaluated by evaluated-points method. Results Mean radiation dose to the patients was significantly reduced from 15. 19mGy to5.66 mGy（ P 〈 0.05 ）, but no significant difference of the image quality in MSCTU was found between the two groups （P〉0.05） Conclusion MSCTU scanning of the normal ureters can be performed at greatly reduced mA and radiation dose without decreasing the image quality.