The Comparative Study of Radiation Reduction with Prospective ECG-triggering Acquisition and Retrospective ECG-gating Acquisition for 64-detector Computed Tomographic Coronary Artery Tomography

Objective Applying the prospective ECG-triggering acquisition and the retrospective ECG-gating acquisition for 64-detector computed tomographic coronary artery imaging to explore a way for reducing effective radiation doses. Materials and Methods 202 suspected coronary heart disease patients were scanned by 64-slice CT coronary angiography,and CTA was performed using retrospective triggering with dose modulation or prospective triggering with/without padding (step and shoot acquisition with additional adjacent phases/single phase acquisition only).Images quality of CTA and effective radiation doses with different acquisition protocols were compared with each other by Group T test,chi-square test and variance analysis. Results Compared to retrospective imaging,prospective imaging reduced radiation exposure by 82.3% as (D-value=14.626,95% CI=11.768-17.484,P=0.001) under120 kVp. Conclusion Compared to retrospective imaging,prospective imaging can significantly reduce radiation exposure on patients whose heart rate less or equal to 65 / cent with a fairly regular rhythm under120 kVp.