实施QC对影像质量与病人剂量影响的研究

目的　探讨实施放射诊断设备质量控制（ＱＣ） 后，病人受照剂量及Ｘ 射线胶片影像质量的变化。方法　ＱＣ前后用热释光剂量探测器测量病人入射体表剂量，并用欧洲共同体（ＣＥＣ） 影像质量标准对已测量剂量的病人Ｘ 射线胶片影像质量进行评价，做统计学分析。结果　Ｘ 射线机实施质量控制后，病人受照剂量有了明显下降（Ｐ＜ ０－０１ 或Ｐ＜ ０－０５），胸部后前位下降了２３％ ，腰椎前后位和腰椎侧位下降了４８％ ，骨盆前后位下降了８８％ 。ＱＣ前、后比较，腰椎侧位片影像质量没有显著差异（Ｐ＞０－０５），而胸部后前位、腰椎前后位及骨盆前后位胶片影像质量反而有所提高（ Ｐ＜０－０１ 或Ｐ＜０－０５）。结论　对Ｘ射线机进行ＱＣ检测后可使病人受照剂量较大幅度地下降，但Ｘ 射线胶片影像质量没有降低，诊断信息没有丢失。

Effect of quality control implementation on image quality of radiographic films and irradiation doses to patients

Objective\ To study the changes in the image quality of radiographic films and the irradiation doses to patients after quality control (QC) implementation. Methods The entrance surface doses (ESD) to patients measured with TLD and the image quality of radiographic films were evaluated on the basis of CEC image quality criteria. Results The ESD to patients were significantly reduced after QC implementation ( P <0 01 or P <0 05)23% for chest PA,48% for lumbar spine AP and LAT,88% for pelvis AP.In comparison with pre QC,the post QC image quality of lumbar spine LAT was not significantly changed ( P >0 05),but the post QC image quality was significantly improved in chest PA,lumbar spine AP and pelvis AP(P0 01 or P <0 05). Conclusion Significantly reduced irradiation dose with improved image quality can be obtained by QC implementation.