Cardio-respiratory motion-corrected 3D cardiac water-fat MRI using model-based image reconstruction.

Area of Science:

• Cardiovascular Imaging
• Medical Physics
• Radiology

Background:

• Myocardial fat infiltration is linked to various cardiomyopathies.
• Accurate imaging of cardiac fat is crucial for diagnosis and management.

Purpose of the Study:

• To develop and evaluate a cardio-respiratory motion-correction technique for model-based water-fat separation in 3D MRI.
• To improve visualization of fatty infiltrations in the heart during free-breathing acquisitions.

Main Methods:

• Utilized a free-breathing, high-resolution 3D Dixon gradient-echo sequence with radial encoding.
• Implemented a model-based water-fat reconstruction combined with a dual-mode registration algorithm for motion estimation.
• Compared motion-corrected 3D images with 2D breath-hold scans and analyzed fat structure sharpness.

Main Results:

• 3D motion-corrected reconstructions provided qualitatively comparable fat structures to standard 2D breath-hold scans.
• Respiratory motion correction improved fat structure sharpness by 32% (±24%), with cardiac motion correction adding a further 15% (±11%).
• Overall sharpness increased by 51% (±27%) compared to motion-averaged reconstructions, enhancing visualization of myocardial fat infiltration in one patient.

Conclusions:

• The developed 3D water-fat separated cardiac MRI technique is feasible, predictable, and acquired during free-breathing.
• Cardio-respiratory motion correction significantly enhances the sharpness and visualization of cardiac fat structures.
• This technique holds promise for improved diagnosis of cardiomyopathies associated with myocardial fat infiltration.