Evaluation of rigid registration methods for whole head imaging in diffuse optical tomography

Area of Science:

• Neuroimaging
• Biomedical Engineering
• Medical Physics

Background:

• Functional brain imaging is crucial for understanding brain development and organization.
• Diffuse optical tomography (DOT) offers a portable, low-cost alternative for infant and patient brain imaging.
• Accurate forward models are essential for reliable DOT imaging results.

Purpose of the Study:

• To evaluate the accuracy of atlas-based DOT models.
• To compare different rigid registration methods for spatial normalization of DOT models.
• To determine the optimal registration method for whole-cortex functional brain imaging.

Main Methods:

• Evaluated atlas-based DOT accuracy on 24 subjects using various rigid registration techniques.
• Developed a multilevel approach to assess geometrical and sensitivity accuracy.
• Correlated accuracy across the full field of view and specific functional subregions.

Main Results:

• Different registration methods yield optimal results for distinct functional brain regions.
• The "nearest point to point" registration method, based on the EEG 19 landmark system, demonstrated superior performance.
• This method improved image quality across the entire field of view covered by the high-density cap.

Conclusions:

• The choice of registration method significantly impacts the accuracy of functional brain region recovery in DOT.
• "Nearest point to point" registration is recommended for high-density DOT imaging of the optically accessible cortex.
• This finding enhances the reliability of DOT for studying brain function in diverse populations.