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作 者:宛然[1] 武春雪[1] 刘澜涛[2] 王霄英[1]
机构地区:[1]北京大学第一医院医学影像科,北京100034 [2]中国疾病预防控制中心辐射防护与核安全学所,北京100088
出 处:《放射学实践》2008年第8期838-840,共3页Radiologic Practice
摘 要:目的:研究乳腺X线摄影中降低射线剂量曝光条件的优化选择。方法:在全自动(kV和mAs均自动,即auto filter)和半自动(手动kV、mAs自动,即auto time)曝光模式下对不同厚度的模体进行曝光,对所得照片影像质量进行评分,并测其剂量。结果:同一厚度模体在不同曝光条件下所得照片影像质量差异无显著性意义,不同厚度模体在autofilter模式下所得照片影像质量差异无显著性意义,即自动曝光控制(automatic exposure contol,AEC)装置工作状态正常。在各种曝光条件组合中,kV高的曝光条件组合X线摄影剂量低;auto filter模式下X线摄影剂量均不是最低的。结论:在乳腺X线摄影的实际工作中,首先应确保AEC的正常工作状态;在不影响照片影像质量的情况下,选用AEC装置的auto time模式适当提高kV,降低摄影剂量。Objective: To study the exposure dose optimization for screen-film mammography. Methods: Phantoms with different thickness were exposed in mode of auto filter and auto time respectively. Scored the quality of the images acquired, and measured the exposure dose. Results:The difference of image qualities with the same thickness in different exposure conditions was not significant, the difference of image qualities with different thickness in the same exposure conditions was not significant either,it means the condition of AEC was normal. In different exposure conditions, the exposure dose was lower when using higher kV,all the exposure doses in mode of auto filter were not the lowest. Conclusion:We should make sure normal condition of automatic exposure control. Basing on the precondition of ensuring the image quality, it's better to use auto time to increase kV and reduce exposure dose.
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