Prospective motion correction in 2D multishot MRI using EPI navigators and multislice-to-volume image registration

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Medical Imaging Technology
• Image Artifact Reduction

Background:

• Multishot 2D MRI sequences are prone to artifacts from subject motion.
• Existing prospective motion correction techniques have limitations for these sequences.

Purpose of the Study:

• To develop and evaluate a novel prospective motion correction technique for multishot 2D MRI sequences.
• To address limitations in real-time motion correction for 2D echo-planar imaging (EPI).

Main Methods:

• Integrated 2D-EPI slice navigators into 2D imaging sequences for real-time motion correction.
• Employed multislice-to-volume image registration using three navigator slices.
• Utilized a slice-iteration scheme to minimize spin-saturation effects.
• Compared performance against PROPELLER using T2-weighted spin echo and RARE sequences.

Main Results:

• Achieved residual motion parameters within ±0.5 mm and ±0.5° during subject motion.
• Demonstrated substantial image quality improvement compared to uncorrected scans.
• The proposed method preserved more anatomical detail than PROPELLER under motion conditions.

Conclusions:

• EPI-navigator-based prospective motion correction with multislice-to-volume registration effectively reduces MRI artifacts.
• The technique minimizes spin-saturation effects and enhances image quality in 2D sequences.
• This method is adaptable for various 2D MRI sequences, improving clinical examinations.