滤过对数字化胸部X射线摄影图像质量和辐射剂量的影响  

Effect of Filter on Image Quality of Digital Chest Radiography and Radiation Dose

作　　者：曲良勇 苑翠红 

机构地区：[1]上海中冶医院放射科,上海200941

出　　处：《中国医疗设备》2014年第2期44-46,69,共4页China Medical Devices

摘　　要：目的研究滤过对数字图像质量和辐射剂量的影响。方法在1、1.5、2、2.5、3 mmAl,1mmAl+1 mmCu、1.5 mmAl+1 mmCu、2 mmAl+1 mmCu、2.5 mmAl+1mmCu、3 mmAl+1 mmCu滤过条件下,分别以70、90、110、130kV进行曝光。用8cm厚度的有机玻璃模拟成人肺部平均厚度,以CDRAD2.0体模评价图像质量,以剂量面积乘积仪测得参数表示辐射剂量,观察不同滤过对mAs、图像质量及辐射剂量的影响。结果在自动曝光条件下摄片,随着滤过厚度的增加或附加高原子序数滤过,mAs明显增加,辐射剂量明显降低。70 kV和90 kV摄片时,附加不同滤过对图像质量有一定影响,130 kV时,附加滤过对图像质量的影响并不明显。结论在保证图像能够满足诊断要求和设备负荷能够承受的前提下,适当增加附加滤过板厚度和利用高原子序数的滤过能降低辐射剂量。Objective To explore the effect of different filter on digital image quality and radiation dose. Methods Under the different filter by 1 mmAl, 1.5 mmAl, 2 mmA1, 2.5 mmA1, 3 mmA1, 1 mmAl＋l mmCu, 1.5 mmAl＋l mmCu, 2 mmAl＋l mmCu, 2.5 mmAl＋l mmCu, 3 mmAl＋l mmCu, 70 kV, 90 kV, 110 kV and 130 kV were exposed respectively. Having a 8 cm organic glass simulating average thickness of adult pulmonary tissue, effect of different filter on mAs, image quality and radiation dose could be observed through image quality evaluated by CDRAD2.0 phantom and radiation dose detected by dose- area product meter. Results Under the automatic exposure mode, with the thicker or higher Z filtration, mAs increased significantly, while radiation dose decreased obviously. Under the exposure of 70 kV and 90 kV, the different filter had evident effects on the image quality, but not under 130 kV. Conclusion Under the premise of calculated image quality and equipment not overload, the appropriate thicker and higher Z filtration can reduce radiation dose.

关 键 词：X线机 多叶准直器 滤过材料 数字化X射线摄影 图像质量 辐射剂量 

分 类 号：R144[医药卫生—公共卫生与预防医学]