中国医疗设备2012，Vol.27Issue(9)：33-37,5.DOI:10.3969/j.issn.1674-1633.2012.09.006
电离室中心-X射线线束偏移距离对多排CTDI100辐射剂量测定的影响
Effect of Offset Distance between X-Ray Beam and Ionization Chamber Center to CTDI100 Radiation Dosage Measurement of Multi-Slice CT
摘要
Abstract
Objective To explore the influence law of offset distance (Do) between ionization chamber center scale and X-ray beam plane of multi-slices CT to the CTDI100 measurement result Methods Head body mold(T6M164) and long pole ionization chamber, which meet 1EC standards, are used to measure the CTDI100 value of Philips Brilliance iCT 256 on axial scanning condition of different offset distance-Results When Do is lem, relevant deviation(Dr) is 0%~5%, when Do is 3cm, Dr is 5%~15%, and when Do is 5cm, Dr is 25%~75%. Conclusion The measurement result of CTDI100 has greater sensitivity for Do, which means the operator should make sure no deviation exist between X-ray beam and ionization chamber center, besides, more attention should be paid to radiation dose in penumbra area. Scattering beam causes the measurement of CTDI100 at 4 points around more discrete, effect of bed to measurement result shows that symmetry of CTDI100 at 4 points outside the center reduces.关键词
多排CT/CT辐射剂量计/CT剂量指数/半影区/测量误差Key words
multi-slices CT/ CT radiation dosage meter/ CT dose index/ penumbra area/ relevant deviation分类
机械制造引用本文复制引用
郑海亮,冯树理,王仁贵,段永利,杨磊,傅岩,赵君..电离室中心-X射线线束偏移距离对多排CTDI100辐射剂量测定的影响[J].中国医疗设备,2012,27(9):33-37,5.基金项目
国家自然基金项目(11005119) （11005119）
首都医科大学附属北京世纪坛医院院级课题(2011C-34)资助. （2011C-34）
