Motion detection with NMR markers using real-time field tracking in the laboratory frame

Area of Science:

• Medical Imaging
• Biophysics
• Magnetic Resonance Imaging

Background:

• Motion artifacts degrade image quality in Magnetic Resonance Imaging (MRI).
• Current motion detection methods often require sequence-dependent calibration, limiting their routine application.
• Accurate motion tracking is crucial for high-resolution and long-duration MRI scans.

Purpose of the Study:

• To develop a calibration-free method for motion detection using nuclear magnetic resonance (NMR) markers.
• To enhance the utility and robustness of NMR-based motion tracking for real-time applications.
• To demonstrate the effectiveness of the proposed method for prospective motion correction in MRI.

Main Methods:

• Utilized two sets of NMR markers for simultaneous magnetic field dynamics observation.
• Employed stationary markers to determine laboratory frame field evolution.
• Used head-mounted markers to calculate real-time rigid-body motion parameters.

Main Results:

• Achieved motion detection precision of 10-30 µm without calibration.
• Demonstrated superior robustness against thermal drift compared to conventional calibration.
• Showcased substantially higher accuracy than economical calibration modes.
• Successfully performed prospective motion correction, maintaining high image quality despite significant head motion.

Conclusions:

• Real-time field tracking enables calibration-free NMR motion detection, overcoming a major obstacle for clinical use.
• This approach enhances motion tracking robustness against system imperfections.
• Facilitates routine application of precise motion detection and correction in MRI.