Quantification of Epicardial Adipose Tissue in Non-ECG-gated Low-radiation-dose MDCT

Objective:To quantify the EAT volume in non-ECG-gated low-radiation-dose MDCT and assess the relationship of EAT volume in non-ECG-gated MDCT in comparison with ECG-gated Coronary CTA.Method:In all,61 patients were enrolled in this study and underwent retrospective ECG-gated coronary CTA and non-ECG-gated low-radiation-dose MDCT for lung cancer screening.The EAT volume was calculated through depicted the epicardium with AW4.4 workstation(GE).The threshold of EAT quantification in non-ECG-gated CT was -195~- 45 Hu.A total of five programs of the thresholds of EAT quantification in coronary CTA would be built(-175~- 25 Hu,-170~- 20 Hu,-165~-15 Hu,-160~-10 Hu,-155~- 5 Hu respectively).Result:The EAT volume quantification in non-ECG-gated MDCT had a significant relationship with the quantifications in ECG-gated Coronary CTA(r=0.996,r=0.997,r=0.997,r=0.997,r=0.996 respectively).When the threshold of EAT quantification in ECG-gated Coronary CTA was -165~-15 Hu,no significant difference was observed for EAT volume quantification with non-ECG-gated MDCT with respect to ECG-gated Coronary CTA(P=0.125).Conclusion:Non-ECG-gated low-radiation-dose MDCT allows quantifying EAT with almost the same consistency and correlation as using ECG-gated Coronary CTA.