Influence Of Snapshot Freeze Motion Correction Algorithm On Image Quality Of Coronary Artery CT Angiography

Purpose:This study aimed to investigate the effect of snapshot freeze(SSF)motion correction algorithm on the motion artifact of coronary CT angiography on different heart rates(HR) in coronary artery angiography(CCTA).Methods:For 113 consecutive patients undergoing CCTA on Discovery CT 750 HD Freedom,standard(STD) and SSF motion correction were performed for each patient, 2 experienced readers independently graded image qualities using a 4-point Likert scale,The image qualities were assessed on per—artery and per—segment level,patients were assigned to 6 different groups based on their average HR during coronary CTA. Comparisons of image quality were performed with Wilcoxon signed-rank tests, and comparisons of percentages of interpretable image quality were performed using Fisher’s exact tests. Results: Image qualitities were higher with the use of SSF than STD(P<0.05) on left anterior descending(LAD), left circumflex(LCX) and right coronary artery(RCA) in both groups.There was no statistic significance for left main coronary artery(P>0.05). SSF showed higher image score than STD on per-segment level(P<0.001).SSF showed higher interpretability than STD on per-artery(P<0.01) in group 3-6,but not for group of 1-2, The per—artery interpretability was significantly higher using SSF in RCA(P<0.01)in group 4-6.Conclusion:The SSF motion correction algorithm reconstruction provided same or even better image quality and interpretability in both groups, it may be more beneficial to the patients with a higher HR.