T1234: A distortion-matched structural scan solution to misregistration of high resolution fMRI data

Area of Science:

• Neuroimaging
• Magnetic Resonance Imaging

Background:

• High-resolution functional MRI (fMRI) at 7 Tesla (7T) faces challenges with suboptimal alignment between functional and structural scans.
• Accurate registration is crucial for detailed analysis, especially for layer-specific fMRI studies.

Purpose of the Study:

• To develop a rapid acquisition method for structural reference data that is distortion-matched and artifact-mitigated for 7T fMRI.
• To improve the quality of structural scans for better alignment with functional neuroimaging data.

Main Methods:

• Introduction of the T1234 sequence protocol, a T1-weighted 2-inversion 3D-EPI sequence with adjustable distortions.
• Optimization of the protocol using a forward Bloch model for T1 quantification.
• Validation in 20 participants at 7T using both structural and functional imaging protocols.

Main Results:

• A fast, distortion-free protocol achieved whole-brain segmentation at 0.8mm isotropic resolution in under 3.5 minutes.
• The method demonstrated robustness across sessions, participants, and three different 7T scanners.
• A distortion-matched protocol facilitated layer-specific fMRI analysis with improved laminar precision.

Conclusions:

• The T1234 structural mapping approach enables precise registration with fMRI data.
• The T1234 method has been successfully implemented, validated, and is available globally.