Quality control and parameter optimization of coronary angiography with 64 multi-slice CT / 中华放射学杂志

ABSTRACT

Objective To control the image quality and to optimize the scan protocols of 64 multi-slice CT coronary imaging by analyzing factors that influence the image quality.Methods Seventy-eight patients with known or suspected CAD underwent CT coronary angiography using 64 multi-slice CT.The image quality in those cases was analyzed retrospectively to derive the optimized scan protocols.The application value of the override function was discussed.The dependency of cardiac reconstruction algorithms and corresponding image quality on patient heart rates was analyzed.In addition,the relationship between heart rate and the contrast-enhancement effect was studied.Results(1)Correct use of override function could improve the quality of cardiac images.(2)For patients with heart rates below 70 beats per minute,the image quality of single-segment reconstruction was satisfactory.For patients with heart rates between 70 and 79 beats per minute,the scores of images reconstructed with two-segments were better than that of single-segment reconstruction.(3)In the group with averaged heart rate of 60.7 beats per minute,the forecast contrast quantity of 70 ml was judged insufficient in 65.7%(23/35)cases;while for the group with averaged heart of 71.1 beats per minute,52.9%(18/34)cases were enhanced well.Conclusion The use of override function,correct segment mode and appropriate contrast quantity could be selected according to the heart rate,which could improve the image quality and reliability.