Rika Fukui, Presenter: Nothing to Disclose

Takuma Shuto, Abstract Co-Author: Nothing to Disclose

Isao Tanaka, Abstract Co-Author: Nothing to Disclose

Yun Shen PhD, Abstract Co-Author: Employee, General Electric Company Researcher, General Electric Company

Haruhiko Machida MD, Abstract Co-Author: Nothing to Disclose

Eiko Ueno MD, Abstract Co-Author: Nothing to Disclose

Xiao Zhu Lin MD, Abstract Co-Author: Nothing to Disclose

He Qing Wang MSc, Abstract Co-Author: Nothing to Disclose

To retrospectively investigate reduction of coronary motion artifacts by a novel motion correction algorithm (MCA) in coronary CT angiography (CCTA) for patients with different heart rates (HRs).

We divided 60 patients who underwent CCTA into 4 groups based on their average HRs as follows: 1) average HR ≤ 59 bpm, 13 patients; 2) 60-69 bpm, 24; 3) 70-79 bpm, 19; 4) ≥ 80 bpm, 4. Two readers, in consensus, evaluated quality of axial images of the left main trunk (the segment 5), anterior descending artery (LAD, the segment 6-8), circumflex artery (LCX, the segment 11, 13), and right coronary artery (RCA, the segment 1-3) reconstructed with and without the MCA at 40% (systole) and 75% of the R-R interval (diastole) using half-scan method. For each different HR group and cardiac phase, per-segment image quality regarding motion artifacts was visually graded using a 5-point scale and compared using Wilcoxon signed rank test, and percentage of per-vessel interpretable image quality (scores, 3-5) with MCA was calculated.

Averaged per-segment image quality score with MCA at the diastole was 4.7 ± 0.6, 4.5 ± 0.7, 3.8 ± 1.0, and 3.2 ± 0.9 for group 1, 2, 3, and 4, respectively; at the systole, 3.0 ± 0.8, 3.5 ± 1.0, 3.8 ± 0.8, and 3.8 ± 0.8; without MCA at the diastole, 4.3 ± 0.9, 4.0 ± 0.9, 3.1 ± 1.2, and 2.5 ± 0.9; at the systole, 2.2 ± 0.9, 2.6 ± 1.1, 3.0 ± 1.0, and 2.8 ± 0.9. For all the groups, the score was significantly better with MCA than without MCA at both the diastole and systole (P < 0.05). With MCA, percentages of per-vessel interpretable image quality at the diastole for the LAD was 100, 99, 99, and 88% for group 1, 2, 3, and 4, respectively; for the LCX, 100, 100, 90, and 75%; for the RCA, 95, 97, 77, and 75%; at the systole for the LAD, 50, 81, 92, and 100%; for the LCX, 50, 92, 87, and 75%; for the RCA, 100, 72, 91, and 83%.

Use of MCA significantly reduced coronary motion artifacts and per-vessel interpretable image quality of ≥ 95% even if reconstructed only at 75% of the R-R interval for patients with average HR ≤ 69 bpm.

Use of a novel MCA can reduce coronary motion artifacts, improve diagnostic accuracy, and increase the indication of step-and-shoot scan to reasonably reduce radiation dose in CCTA.

Fukui, R, Shuto, T, Tanaka, I, Shen, Y, Machida, H, Ueno, E, Lin, X, Wang, H, Reduction of Coronary Motion Artifacts by a Novel Motion Correction Algorithm in Coronary CT Angiography for Patients with Different Heart Rates.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14017471.html