优化骶尾骨侧位数字化X线摄影的方法学研究

Methodology research on optimization of digital radiography in sacrococcyx lateral position

目的:评价曝光辐射剂量及图像后处理2种优化措施对骶尾骨侧位数字化X线摄影影像质量的影响。方法:利用等效体模和矩形波测试卡选取适用于临床优化的曝光条件。37例患者每例均先后使用该优化的曝光条件和设备默认的曝光条件,摄取骶尾骨侧位的初级图像共74幅,比较2次曝光所测得的毫安秒值和剂量面积乘积的统计学差异。分别使用设备自带的图像后处理软件包中的默认参数与优化参数对所有初级图像进行后处理,得到最终图像共148幅。由2位高年资放射科医师参照欧共体标准对最终图像的影像质量进行主观评价。结果:优化曝光条件下测得的辐射剂量较默认曝光条件显著降低(P<0.01)。2种不同的曝光条件对最终图像的影像质量没有显著性影响(P=0.13),而2种不同的图像后处理参数则显著地影响了最终图像的影像质量(P<0.01)。结论:数字化骶尾骨侧位摄影检查中,可在一定范围内减低辐射剂量,同时依靠图像后处理软件的优化,同样能得到满足诊断要求的高质量图像。

Objective To evaluate exposure dose and image postprocessing for optimizing digital radiography in sacrococcyx lateral position.Methods Optimized exposure conditions applicable to clinical practice were selected with equivalent phantom and square wave test card.Totally 37 patients underwent the exposures both on optimized and default conditions in succession for achieving 74 primary images in sacrococcyxgeal lateral position.The statistical differences of milliampere-second（m As）and dose area product（DAP） measured on two exposures were tested.All primary images were then treated using both default parameters and optimized parameters of the image post-processing software respectively,yielding 148 final images in total.Two radiologists subjectively evaluated the image quality of final images with reference to EC standards.Result The radiation dose measured under the optimized exposure condition was significantly lower than that under the default condition（P〈0.01）.Changes on exposure condition had not significantly impact on the image quality of final images（P=0.13）,while changes on the image processing parameters did（P〈0.01）.Conclusion To meet the diagnostic requirements,high-quality images of sacrococcyxgeal lateral position can be carried out by optimized image post-processing while reducing the radiation dose within a certain range during the digital radiography examinations.