Trajectory correction for free-breathing radial cine MRI

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Magnetic Resonance Imaging

Background:

• Radial acquisitions are prone to trajectory errors, degrading image quality.
• Existing trajectory correction methods rely on limited pre-scan data.

Purpose of the Study:

• To introduce and evaluate a novel trajectory correction method for radial MRI.
• To compare the new method against an existing technique using all available radial spokes.

Main Methods:

• Developed a new trajectory correction method utilizing all spokes of a radial acquisition.
• Compared performance with a two-spoke pre-scan calibration method.
• Evaluated both magnitude and phase-based shift estimations, with and without B0 correction, using mouse cardiac scans.

Main Results:

• The proposed method demonstrated superior image quality and artifact reduction compared to the existing method.
• Phase-based corrections were generally more effective than magnitude-based methods.
• B0 correction further enhanced image quality, and the new technique reduced navigator signal modulation.

Conclusions:

• The novel trajectory correction method effectively reduces artifacts in radial MRI, particularly in mouse cardiac imaging.
• This advancement facilitates faster imaging protocols by improving image quality and navigator signal stability.