Application of Size-specific Dose Estimates in Cardiac CTA Examination of School-age Children
Objective To explore the differences in radiation doses in School-age children by comparing volume CT dose index(CTDIvol)and body size-specific dose estimates(SSDE)in cardiac CTA examinations,and to explore the reasons.Methods A retrospective analysis was conducted on the imaging data of 77 children's cardiac CTA examinations in our hospital.Manual outlining of the center layer contour as the region of interest(ROI)was performed,and the mean maximum lateral diameter(LAT),average CT value(CTROI),and area(AROI)of the ROI were measured.According to LAT,the subjects were divided into three groups:Group A(LAT＜22cm,n=33);Group B(22cm≤LAT＜25cm,n=26);Group C(25cm≤LAT＜30cm,n=18).The conversion factors FDW and SSDEDW were calculated and recorded.The differences between CTDIvol and SSDEDW were analyzed,and the correlation between gender,age,AROI,and LAT with SSDEDW was studied using multiple regression analysis.Results The SSDEDW values for Groups A,B,and C were 197.37％,192.01％,and 187.68％higher than those of CTDlvol.There were significant differences between CTDIvol and SSDEDW among the three groups(P＜0.05).A positive linear relationship was observed between LAT and SSDEDW(P＜0.05).Gender,age,and AROI showed no significant correlation with SSDEDW(P＞0.05).Conclusion Compared with CTDIvol,SSDEDW is more accurate in assessing radiation dose in children's cardiac CTA.There is a positive linear relationship between LAT and SSDEDW,whereby LAT increases by 1cm,SSDEDW increases by 0.44MGy.
万方数据
维普
