학술논문
不同心率前后门控CT冠状动脉成像图像质量与辐射剂量的相关性分析 / Correlations between image quality and radiation dose in prospective and retrospective ECG-gated CT coronary angiography in patients with different heart rates
Document Type
Academic Journal
Source
中国医学物理学杂志 / Chinese Journal of Medical Physics. 41(2):185-190
Subject
Language
Chinese
ISSN
1005-202X
Abstract
目的:分析不同心率前后门控CT冠状动脉(简称冠脉)成像图像质量与辐射剂量的相关性.方法:收集行256层螺旋CT冠脉成像检查患者135例,其中行前门控扫描(即前瞻性心电门控)66例(前门控组),根据患者心率分为≤80次/min(前门控低心率亚组,39例)与>80次/min组(前门控高心率亚组,27例);行后门控扫描(即回顾性心电门控)69例(后门控组),其中心率≤80次/min者45例(后门控低心率亚组),>80次/min者24例(后门控高心率亚组);比较4组基线资料、图像质量[平均CT值、图像噪声、信噪比(SNR)、主观图像质量评分]及辐射剂量[CT容积剂量指数(CTDIvol)、剂量长度乘积(DLP)、有效剂量(ED)]差异,分别分析前门控组与后门控组中图像质量与心率、辐射剂量的相关性.结果:前门控低心率亚组与后门控低心率亚组的心率均低于前门控高心率亚组与后门控高心率亚组(P<0.05),4组平均CT值、图像噪声、SNR及主观图像质量评分比较,差异均无统计学意义(P>0.05).前门控低心率亚组CTDIvol、DLP、ED均显著低于前门控高心率亚组及后门控低心率亚组、后门控高心率亚组(P<0.05),前门控高心率亚组则均低于后门控低心率亚组及后门控高心率亚组(P<0.05).Pearson相关系数分析显示,前门控组与后门控组中,受检者平均CT值、图像噪声、SNR、主观图像质量评分与心率、CTDIvol、DLP、ED均无显著相关性(P>0.05).结论:256层螺旋CT冠脉成像主观与客观图像质量与辐射剂量无关,前门控扫描较后门控扫描可降低辐射剂量,且保证图像质量,对于符合条件的高心率患者同样适用,且能降低辐射剂量水平,适合在临床推广应用.
Objective To explore the correlations between image quality of prospective and retrospective electrocardiogram(ECG)-gated CT coronary angiogram and radiation dose in patients with different heart rates.Methods A total of 135 patients undergoing 256-slice spiral CT coronary angiography were enrolled in the study.Among them,66 cases received prospective ECG-gated scanning(prospective ECG-gated group)and further divided into two subgroups with heart rate≤80 beats/min(prospective ECG-gated+low heart rate subgroup,n=39)and>80 beats/min(prospective ECG-gated+high heart rate subgroup,n=27).The other 69 cases underwent retrospective ECG-gated scanning(retrospective ECG-gated group),including 45 cases with heart rate≤80 beats/min(retrospective ECG-gated+low heart rate subgroup)and 24 with heart rate>80 beats/min(retrospective ECG-gated+high heart rate subgroup).The baseline data,image quality[mean CT value,image noise,signal-to-noise ratio(SNR),subjective image quality score]and radiation dos[CT volume dose index(CTDIvol),dose length product(DLP),effective dose(ED)]were compared among 4 subgroups.The correlations of image quality with heart rate and radiation dose in prospective and retrospective ECG-gated groups were analyzed.Results The heart rates in prospective and retrospective ECG-gated+low heart rate subgroups were lower than those in prospective and retrospective ECG-gated+high heart rate subgroups(P<0.05).When comparing the mean CT value,image noise,SNR and subjective image quality score among 4 subgroups,no statistically significant differences were observed(P>0.05).The CTDIvol,DLP and ED in prospective ECG-gated+low heart rate subgroup were significantly lower than those in the other 3 subgroups(P<0.05),and the indicators in prospective ECG-gated+high heart rate subgroup were lower than those in retrospective ECG-gated group(including low and high heart rate subgroups)(P<0.05).Pearson correlation coefficient analysis revealed that the mean CT value,image noise,SNR,subjective image quality score had no significant correlation with heart rate,CTDIvol,DLP and ED in prospective and retrospective ECG-gated groups(P>0.05).Conclusion The subjective and objective image quality of 256-slice spiral CT coronary angiography is not correlated with radiation dose.Prospective ECG-gated scanning can reduce the radiation dose and ensure the image quality as compared with retrospective ECG-gated scanning.This holds true for eligible patients with high heart rate,and the former can effectively reduce radiation exposure.Therefore,prospective ECG-gated scanning is worthy to be promoted in clinic.
Objective To explore the correlations between image quality of prospective and retrospective electrocardiogram(ECG)-gated CT coronary angiogram and radiation dose in patients with different heart rates.Methods A total of 135 patients undergoing 256-slice spiral CT coronary angiography were enrolled in the study.Among them,66 cases received prospective ECG-gated scanning(prospective ECG-gated group)and further divided into two subgroups with heart rate≤80 beats/min(prospective ECG-gated+low heart rate subgroup,n=39)and>80 beats/min(prospective ECG-gated+high heart rate subgroup,n=27).The other 69 cases underwent retrospective ECG-gated scanning(retrospective ECG-gated group),including 45 cases with heart rate≤80 beats/min(retrospective ECG-gated+low heart rate subgroup)and 24 with heart rate>80 beats/min(retrospective ECG-gated+high heart rate subgroup).The baseline data,image quality[mean CT value,image noise,signal-to-noise ratio(SNR),subjective image quality score]and radiation dos[CT volume dose index(CTDIvol),dose length product(DLP),effective dose(ED)]were compared among 4 subgroups.The correlations of image quality with heart rate and radiation dose in prospective and retrospective ECG-gated groups were analyzed.Results The heart rates in prospective and retrospective ECG-gated+low heart rate subgroups were lower than those in prospective and retrospective ECG-gated+high heart rate subgroups(P<0.05).When comparing the mean CT value,image noise,SNR and subjective image quality score among 4 subgroups,no statistically significant differences were observed(P>0.05).The CTDIvol,DLP and ED in prospective ECG-gated+low heart rate subgroup were significantly lower than those in the other 3 subgroups(P<0.05),and the indicators in prospective ECG-gated+high heart rate subgroup were lower than those in retrospective ECG-gated group(including low and high heart rate subgroups)(P<0.05).Pearson correlation coefficient analysis revealed that the mean CT value,image noise,SNR,subjective image quality score had no significant correlation with heart rate,CTDIvol,DLP and ED in prospective and retrospective ECG-gated groups(P>0.05).Conclusion The subjective and objective image quality of 256-slice spiral CT coronary angiography is not correlated with radiation dose.Prospective ECG-gated scanning can reduce the radiation dose and ensure the image quality as compared with retrospective ECG-gated scanning.This holds true for eligible patients with high heart rate,and the former can effectively reduce radiation exposure.Therefore,prospective ECG-gated scanning is worthy to be promoted in clinic.