High efficiency coronary MR angiography with nonrigid cardiac motion correction

Area of Science:

• Cardiovascular Imaging
• Medical Physics
• Image Reconstruction

Background:

• Four-dimensional (4D) coronary MR angiography (MRA) is crucial for visualizing coronary arteries.
• Cardiac motion artifacts degrade image quality and limit diagnostic accuracy in 4D coronary MRA.
• Improving coronary visualization is essential for better detection and characterization of coronary artery disease.

Purpose of the Study:

• To enhance the coronary visualization quality of 4D coronary MRA.
• To develop and validate a novel method combining cardiac motion correction and iterative reconstruction.
• To improve the diagnostic performance of 4D coronary MRA through superior image quality.

Main Methods:

• Utilized a contrast-enhanced, spoiled gradient echo sequence with 3D radial trajectory and self-gating for 4D coronary MRA acquisition at 3 Tesla.
• Implemented respiratory motion correction and nonrigid registration between quiescent phases for cardiac motion information.
• Applied iterative reconstruction using motion information and k-space data to generate final images, compared to conventional single-window reconstruction.

Main Results:

• The proposed method significantly improved apparent signal-to-noise ratio (aSNR) from 11.89 ± 3.76 to 13.97 ± 5.21 (P = 0.005).
• Scan efficiency was markedly increased from 18.8% ± 6.0% to 40.9% ± 9.7% (P < 0.001).
• Significant improvements in coronary sharpness were observed for the left main, proximal and middle right coronary artery, and proximal left anterior descending artery.

Conclusions:

• Cardiac motion-corrected iterative reconstruction significantly enhances coronary visualization quality in 4D coronary MRA.
• The developed technique offers improved image quality and diagnostic potential for evaluating coronary arteries.
• This advancement represents a significant step forward in non-invasive cardiac imaging for coronary artery disease.