Snapshot Freeze Technique and Multi-sector Reconstruction on Improving Image Quality of Coronary CT Angiography / 中国医学影像学杂志

ABSTRACT

PurposeTo evaluate the motion correction algorithm (snapshot freeze, SSF) and multi-cycle reconstruction on the imaging quality and interpretation of coronary CT angiography (CCTA).Materials and Methods Sixty patients with suspected coronary heart disease were divided into two groups according to the heart rate. Twenty-ifve patients with heart rate ≤65 beats per minute underwent prospectively ECG-gated CCTA on gemstone CT. Image quality and interpretability of standard (STD) and SSF reconstructions at 75% R-R interval were compared. Thirty-five patients with heart rate>65 beats per minute underwent retrospective ECG-gated CCTA. Image quality and interpretability of STD and SSF reconstructions at 45% and 75% R-R interval were compared. The image qualities and interpretability were assessed based on coronary artery segment, coronary artery bifurcation and overall coronary artery.Results For 25 patients with prospectively ECG gated CCTA, SSF reconstructions showed higher interpretability than STD reconstructions on per-segment level [96.3% (341/354)vs 90.7% (321/354),P0.05). For 35 patients with retrospective ECG-gate CCTA, SSF reconstructions at 45% R-R interval showed higher interpretability (P0.05). Image qualities with SSF were higher than that with single and double sector STD reconstructions (P0.05). There were signiifcant different for LAD, LCX and RCA on both 45% and 75% R-R interval images (P<0.01,P<0.001). Conclusion SSF may improve the image quality and interpretability of CCTA images using prospectively and retrospective ECG-gated techniques, especially for improving the image quality.