Evaluation of the optimal image reconstruction interval for coronary artery imaging using 64-slice computed tomography.

ABSTRACT

BACKGROUND: Cardiac computed tomography (CT) has become an established complement in cardiac imaging. Thus, optimized image quality is diagnostically crucial. PURPOSE: To prospectively evaluate whether, by using 64-slice CT, a specific reconstruction interval can be identified providing best image quality for all coronary artery segments and each individual coronary artery. MATERIAL AND METHODS: 311 coronary segments of 14 men and seven women were analyzed using 64-slice CT. Data reconstruction was performed in 5% increments from 5-100% of the R-R interval. Four experienced observers independently evaluated image quality of the coronary arteries according to the AHA classification. A three-point ranking scale was applied 1, very poor, no evaluation possible; 2, diagnostically sufficient quality; 3, highest image quality, no artifacts. RESULTS: The best reconstruction point for all segments was found to be 65% of the R-R interval (mean value 2.4+/-0.5; P<0.05). On a per-artery basis, best image quality was again achieved at 65% of the R-R interval RCA 2.2+/-0.4, LCA 2.4+/-0.5, LM 2.5+/-0.2, LAD 2.3+/-0.4, LCX 2.3+/-0.5. CONCLUSION: By using 64-slice CT, the need for adjusting the reconstruction point to each coronary segment might be overcome. Best image quality was achieved with image reconstruction at 65% of the R-R interval for all coronary segments as well as each coronary artery.