摘要
目的:研究X射线计算机断层扫描(CT)设备质量控制检测测算方法和检测结果,以建立其质量控制检测指标的处置界限。方法:基于美国放射学会(ACR)及美国医学物理学会(AAPM)CT设备检测规范标准,对Philips Brilliance iCT Elite型CT加权剂量指数、层厚、CT值、定位光精度、噪声、空间分辨率、密度分辨率和均匀性等进行质量控制检测;根据ACR标准要求分别扫描76-414型160 mmCT剂量头模以及Catphan 500型CT性能检测体模,对扫描所得图像进行质量控制检测参数测算,建立质量控制检测指标的处置界限。结果:Philips Brilliance iCT Elite CT加权剂量指数检测均值为(44.787±0.645)mGy,最大偏差1.68 mGy,处置界限为CT加权剂量指数(CTDIw)变化≤5%;空间分辨率处置界限为标准算法≥7 LP/cm、骨算法≥9 LP/cm;密度分辨率处置界限为能够分辨0.5%对比度差异圆柱的直径≤4 mm;定位光精度处置界限应≤1 mm;层厚偏差处置界限应≤0.6 mm;噪声处置界限应≤0.4%;CT值均匀性处置界限应≤2 HU;水的CT值处置界限应≤±4 HU;诊断床运动精度处置界限为≤1 mm;CT值线性处置界限(1.95±0.02)×10-4。结论:系统质量控制检测结果均在处置界限范围内,且设备运行良好。
Objective:To research calculating methods and testing results of quality control(QC)test of computed tomography(CT)equipment and establish the action limits of test indicators of QC.Methods:Based on the test code standards of CT equipment of ACR and AAPM,a series of indicators included CT dose index weighted(CTDIw),slice thickness,CT value,precision of positioning light,noise,spatial resolution,density resolution and uniformity etc.of Philips Brilliance iCT Elite CT were implemented QC testing.According to the ACR standard,the 160 mm CT dose head phantom of 76-414 type and CT performance phantom of Catphan 500 type were respectively scanned,and the images that obtained from scan were implemented measurement and calculation of QC detecting parameters,and the action limits of QC detection indicators were established.Results:The mean value of weighted dose indexes of Philips Brilliance iCT Elite CT was(44.787+0.645)mGy,and its maximum deviation was 1.68 mGy,and the action limits was that the change of CTDIw was less than 5%.The action limits of spatial resolution was that canonical algorithm was larger or equal to 7 LP/cm,and bone algorithm was larger or equal to 9 LP/cm.And the action limits of density resolution was that the columnar diameter was less or equal to 4mm when 0.5%contrast difference could be distinguished.And the action limits of precision of positioning light should be less or equal to 1mm.And action limits of slice thickness deviation,noise,the uniformity of CT value,CT value of water,the kinematic accuracy of diagnostic bed and linearity of CT value were less or equal to 0.6 mm,0.4%,2HU,±4HU,1mm value and(1.95+0.02)×10-4,respectively.Conclusion:All of test results of this system QC are within the range of action limits,and the equipment operations is well.
作者
陈坚
陈自谦
刘冰川
付丽媛
钟群
肖慧
许尚文
CHEN Jian;CHEN Zi-qian;LIU Bingchuan(Center of Medical Image,900 Hospital of the Joint Logistics Team(The Former Fuzhou General Hospital of Nanjing Military Command),Fuzhou 350025,China)
出处
《中国医学装备》
2018年第12期20-25,共6页
China Medical Equipment
基金
国家重点研发计划数字诊疗装备研发重点专项(2016YFC0103103)"相关临床应用软件质量控制检测规范与评价标准编制"
