The role of latency period in quality management for free-breathing coronary wall MRI.

The aim of the present study was to determine the effects of the latency period on the performance of free-breathing coronary wall MRI. With the approval of IRB, 70 participants were recruited for coronary wall magnetic resonance imaging (MRI) and provided written informed consent. In 35 subjects, right coronary segments (RCA1-3) were imaged first; in the remaining subjects, the left coronary segments (LM and LAD1-3) were imaged first. The images were classified into groups; group 1 contained right coronary images from the subjects whose right coronary segments were imaged first and left coronary images from the subjects whose left coronary segments were imaged first. Group 2 contained the other coronary segments. The image scores (ranked1-3), latency periods, drift of the position of the navigator (NAV), scan efficiency were compared between image groups. Image group 1 has higher scores (1.66 ± 0.55 vs. 1.46 ± 0.51), shorter latency periods (32.04 ± 4.24 vs. 44.22 ± 5.57 min), lower drift in the location of the NAV (1.90 ± 1.27 mm vs. 2.61 ± 1.71 mm) and higher scan efficiency (32.7 ± 7.6 vs. 29.9 ± 7.9%) than group 2. Long latency periods have a significantly negative impact on the image quality of coronary wall MRI.