MSCT低剂量扫描对腰椎图像质量影响的初步研究

The study of the effect on the image quality in low-dose MSCT of lumbar vertebrae

目的探讨MSCT低剂量扫描技术(单纯降低mAs),受检者所接受辐射剂量及其对图像质量的影响。方法将120名受检者随机分成实验组(60例)和对照组(60例),两组分别采用低剂量(100mAs)和常规剂量(200mAs)进行扫描,其余参数完全相同,测量并记录两组患者的辐射剂量和图像噪声,对各组图像质量进行评价。结果两组患者所接受的辐射剂量分别为:5.72±0.32和11.45±0.76,差异有统计学意义(P<0.05),实验组所接受的剂量显著低于对照组。图像的评价结果显示:随着mAs降低,骨小梁及软组织显示略模糊,图像噪声增加,但实验组图像仍可满足临床诊断(两组图像评分分别为11.07±0.82和11.30±0.79,P>0.05)。结论单纯降低mAs的腰椎MSCT低剂量扫描技术可大幅降低辐射剂量,所获得的图像基本能满足临床诊断要求,可作为常规应用于临床,值得进一步推广应用。

Objective To determine the effect of reducing mAs on the diagnostic quality of images and the radiation dose in patients undergoing lumbar vertebrae MSCT. Methods 120 cases were divided randomly divided into two groups：expemental group （low dose group,100 mAs group, 60 cases） and control group （200 mAs group, 60 cases）. The quality of imaging and radiation dose were compared among three groups. Results The CTDIvol of two groups were 5.72 ± 0.32 and 11.45±0.76, respectively. There were significant differences among three groups （ P 〈0.05）. However, the quality of images between two groups was not different （ P 〉0.05）, the scores of image quality between two group were 1.07± 0.82 and 11.30±0.79. Conclusion The low-dose scan mode could be used in routine examination of lumbar vertebrae using MSCT.