A within-coil optical prospective motion-correction system for brain imaging at 7T

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Medical Imaging Technology
• Biomedical Engineering

Background:

• Motion artifact is a significant limitation in high-field MRI, hindering clinical applications.
• Existing prospective motion correction methods, like mouthpiece-based systems, can be cumbersome.
• Advancements are needed to improve image quality and patient comfort during 7 Tesla MRI scans.

Purpose of the Study:

• To develop and validate an optical prospective motion correction (O-PMC) system for 7 Tesla MRI.
• To assess the system's ability to correct motion artifacts and enable ultra-high-resolution imaging.
• To provide a more accessible O-PMC solution by eliminating the need for a mouthpiece.

Main Methods:

• A custom-built, within-coil camera was designed to track an optical marker on the subject's forehead.
• The system was tested on phantoms and 7 human volunteers using 3D-IR-FSPGR and 2D gradient echo sequences.
• Image quality was blindly assessed by neuroradiologists, with deliberate motion introduced and corrected.

Main Results:

• The O-PMC system effectively corrected both deliberate and involuntary motion in phantom and human studies.
• High-quality images were acquired without artifacts, even with significant motion.
• Quantitative analysis showed significant improvements in image quality (P < .001), enabling ultra-high-resolution visualization and robust alignment of serial scans.

Conclusions:

• A within-coil camera enables effective optical prospective motion correction at 7 Tesla MRI.
• The system facilitates ultra-high-resolution imaging and robust scan alignment.
• This mouthpiece-free approach enhances the accessibility of motion correction for 7 Tesla MRI examinations.