The Influence of Reconstruction Algorithm and Heart Rate on Coronary Artery Image Quality and Stenosis

Objective:We wanted to evaluate the impact of two reconstruction algorithms (halfscan and multisector) on the image quality and the accuracy of measuring the severity of coronary stenoses by using a pulsating cardiac phantom with different heart rates (HRs). Materials and Methods: Simulated coronary arteries with different stenotic severities (25, 50, 75%) and different luminal diameters (3, 4, 5 mm) were scanned with a fixed pitch of 0.16 and a 0.35 second gantry rotation time on a 64-slice multidetector CT. Both reconstruction algorithms (halfscan and multi-sector) were applied to HRs of 40-120 beats per minute (bpm) at 10 bpm inter-vals. Three experienced radiologists visually assessed the image quality and they manually measured the stenotic severity. Results: Fewer measurement errors occurred with multisector reconstruction (p = 0.05), a slower HR (p < 0.001) and a larger luminal diameter (p = 0.014); measurement errors were not related with the observers or the stenotic severity. There was no significant difference in measurements as for the reconstructio