Optimized respiratory-resolved motion-compensated 3D Cartesian coronary MR angiography.

Area of Science:

• Medical Imaging
• Cardiovascular MRI
• Image Reconstruction

Background:

• Coronary artery imaging is crucial for diagnosing cardiovascular disease.
• Free-breathing 3D whole-heart coronary magnetic resonance angiography (CMRA) acquisitions are challenging due to respiratory motion.
• Existing methods like XD-GRASP offer respiratory-resolved imaging but can struggle with irregular breathing.

Purpose of the Study:

• To develop a robust and efficient reconstruction framework for high-quality, motion-compensated, respiratory-resolved images from Cartesian CMRA.
• To improve the visualization of coronary arteries during free-breathing acquisitions.

Main Methods:

• Proposed Optimized Respiratory-resolved Cartesian Coronary MR Angiography (XD-ORCCA) framework.
• Incorporated 2D beat-to-beat translational motion information extracted from image navigators to increase respiratory dimension sparsity.
• Compensated for 2D translational motion within each respiratory phase.
• Tested on 10 healthy subjects and 2 patients with cardiovascular disease, compared against XD-GRASP.

Main Results:

• XD-ORCCA provided high-quality respiratory-resolved images with clear visualization of coronary arteries, even with irregular breathing.
• XD-ORCCA improved the visibility and sharpness of coronary arteries compared to XD-GRASP.
• Significant improvements (p < .05) in visible vessel length and proximal vessel sharpness were observed with XD-ORCCA.
• XD-GRASP showed motion blurring in cases of larger motion amplitudes and irregular breathing.

Conclusions:

• A robust, respiratory-resolved, motion-compensated framework (XD-ORCCA) for Cartesian CMRA was developed and validated.
• XD-ORCCA delivers high-quality images across all respiratory phases, regardless of breathing pattern regularity.
• The method offers superior performance compared to XD-GRASP, particularly in challenging respiratory conditions.