摘要
目的通过建立本医疗机构胸部CT辐射剂量参考水平与警示值,并以此指导本院进行胸部CT扫描方案与检查流程的优化,控制CT受检者所受剂量水平。方法连续调取浙江大学医学院附属第二医院2018年1月1日至2019年12月31日进行胸部CT扫描的205511例受检者资料,根据检查时间将受检者分为改进前和改进后两组。改进前组为2018年度进行胸部CT检查的受检者,共90507例,改进后组为2019年度进行检查的受检者,共115004例。设定2018年度胸部CT辐射剂量分布的均值为本院胸部CT辐射剂量指导水平(DRL),第75个百分位数和第25个百分位数为本院辐射剂量诊断参考范围(diagnostic reference range,DRR)的上限和下限,第97.5个百分位数为本院CT辐射剂量警示值,超过DRR上限则认为辐射剂量偏高,超过警示值则认为辐射剂量超高。根据2018年度胸部CT超高剂量扫描的原因分析结果,对2019年度受检者的胸部CT的扫描方案与检查流程进行改进。统计改进前后行胸部平扫CT、胸部增强CT、肺癌筛查低剂量CT的受检者人次、偏高剂量扫描人次、超高剂量扫描人次、单次扫描剂量;统计改进前后因不同原因造成剂量超高的人次、占比。将改进前后两组受检者各项参数进行统计学比较。结果改进后本院胸部平扫CT受检者的平均扫描剂量下降8.67%,两组比较差异有统计学意义(t=55.71,P<0.05),胸部低剂量CT受检者的平均扫描剂量下降20.13%,差异有统计学意义(t=81.99,P<0.05);改进后胸部增强CT受检者的平均扫描剂量与改进前差异无统计学意义(P>0.05);改进后辐射剂量偏高的胸部CT受检者比率较改进前减少9.18%,其中胸部平扫CT、胸部低剂量CT受检者比率分别减少3.66%、17.15%,改进后辐射剂量偏高的胸部增强CT受检者比率增加1.7%;改进后辐射剂量超高的胸部平扫CT、胸部增强CT、胸部低剂量CT受检者比率较改进前分别减少0.55%、1.06%、1.74%;超高剂量扫描的受检者中,改进后剂量可优化的受检者比率较改进前分别减少4.72%、31.49%、19.18%。结论建立本院胸部CT辐射剂量参考水平及剂量警示值有助于推动剂量优化,降低受检者平均剂量,避免高剂量扫描。
Objective To optimize the scheme and process of chest CT scanning and control the dose level to the examined individuals by establishing the diagnostic reference level(DRL)and warning dose value from chest CT examinations in our hospital.Methods The medical records for 205511 examined individuals,who had undergone chest CT scans in the Second Affiliated Hospital of Zhejiang University Medical College from January 1,2018 to December 31,2019,were reviewed consecutively.For the two-year examination periods,these examined individuals were divided into two groups,one for 2018 totalling 90507 and another for 2019 with a total of 115004.The mean value of doses from chest CT scans in 2018 was set as the DRL for the hospital,with the 75th and 25th percentiles as the upper and lower limits of diagnostic reference range(DRR)and the 97.5th percentiles as the warning dose values.The doses above the upper limit of DRR were considered to be relatively-high whearas the ones exceeding the warning dose value to be over-high.Based on the analysis of the over high dose in 2018,the scanning scheme and inspection process of the chest CT scans were improved in 2019.The number of examinations were estimated for the 2018 period for chest plain CT scans,chest enhancement CT scans,lung cancer screening low-dose CT scans,and relatively-high and over-high dose CT scans,as well as the single scanning doses to the examined in the two groups.The number of examinations resulting in high dose to the examined due to different reasons before and after the improvement were studied.The various parameters on the examined in the two groups were compared statistically.Results After the improvement,the average dose from chest plain CT scans decreased by 8.67%,with the statistically significant difference as compared with before improvement(t=55.71,P<0.05).The average dose from low-dose chest CT scans fell by 20.13%with statistically significant difference(t=81.99,P<0.05).The fraction of the examinations with slightly-high doses arising from chest plain CT scans and low dose chest CT scans dropped by 3.66%and 17.15%,respectively.The fraction of the examinations with slightly-high dose from chest enhanced CT increased by 1.7%.The fraction of the examinations with over-high dose from chest plain CT scans,enhanced CT scans and low-dose CT scans decreased by 0.55%,1.06%and 1.74%,respectively.After improvement,the optimized fraction of the examinations with over-high dose,dropped by 4.72%,31.49%and 19.18%respectively.Conclusions The establishment of the DRL and the warming dose value of for chest CT examinations in our hospital is helpful to find out the cause of high dose scanning,promote the optimization of dose,reduce the average dose to the examinedes,and avoid using excessive dose during scanning.
作者
王鑫宏
丁文洪
徐梦溪
章伟敏
张敏鸣
Wang Xinhong;Ding Wenhong;Xu Mengxi;Zhang Weimin;Zhang Minming(Department of Radiology,Second Affiliated Hospital of Zhejiang University Medical College,Hangzhou 310009,China)
出处
《中华放射医学与防护杂志》
CAS
CSCD
北大核心
2020年第7期543-548,共6页
Chinese Journal of Radiological Medicine and Protection
基金
浙江省医药卫生科技计划(2018KY093,2018PY014)。
关键词
辐射
剂量
胸部
优化
Radiation
Dose
Chest
Optimization
