Objective To investigate the effects of different contrast injection schemes on the image quality of triple-rule-out com-puted tomography angiography(TRO-CTA).Methods A total of 691 patients with acute chest pain who underwent TRO-CTA exami-nation from multiple centers were prospectively selected and randomly divided into mixed group and unmixed group according to dif-ferent contrast injection methods.The image quality of aorta,pulmonary artery and coronary artery in the two groups was evaluated subjectively and objectively and the radiation dose was calculated.Results There were no significant differences in subjective image quality scores,aorta and coronary CT values,signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)between the two groups(P>0.05),while there were significant differences in pulmo-nary CT values,SNR,CNR and radiation dose between the two groups(P<0.05).Conclusion The utilization of a mixed contrast injection scheme in TRO-CTA can satisfy diagnostic require-ments while ensuring a low proportional dosage and reduced radiation dose,which has clinical application value.

Objective To investigate the effects of different contrast injection schemes on the image quality of triple-rule-out com-puted tomography angiography(TRO-CTA).Methods A total of 691 patients with acute chest pain who underwent TRO-CTA exami-nation from multiple centers were prospectively selected and randomly divided into mixed group and unmixed group according to dif-ferent contrast injection methods.The image quality of aorta,pulmonary artery and coronary artery in the two groups was evaluated subjectively and objectively and the radiation dose was calculated.Results There were no significant differences in subjective image quality scores,aorta and coronary CT values,signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)between the two groups(P>0.05),while there were significant differences in pulmo-nary CT values,SNR,CNR and radiation dose between the two groups(P<0.05).Conclusion The utilization of a mixed contrast injection scheme in TRO-CTA can satisfy diagnostic require-ments while ensuring a low proportional dosage and reduced radiation dose,which has clinical application value.