Combined multi-scale mesh and full-matrix inversion for enhancing time-domain breast diffuse optical tomography.

Area of Science:

• Biomedical Optics
• Medical Imaging
• Computational Phantoms

Background:

• Time-domain diffuse optical tomography (TD-DOT) reconstructs optical properties but faces challenges with ill-posed inverse problems and low spatial resolution.
• Truncated singular value decomposition (TSVD) is effective for DOT inversion but poses storage issues for 3D volumetric imaging, particularly in dense regions like the breast.

Purpose of the Study:

• To develop and validate a multi-scale mesh strategy to address the storage limitations of TSVD in 3D DOT of the breast.
• To enhance the accuracy and feasibility of reconstructing optical properties using TSVD by optimizing mesh resolution for forward and inverse calculations.

Main Methods:

• A multi-scale mesh approach integrating computed tomography (CT) anatomical geometry was employed.
• A fine mesh was utilized for accurate forward calculations, while a coarse mesh was used for the inversion process to enable whole-weighting matrix inversion via TSVD.

Main Results:

• The proposed strategy successfully overcame the storage challenge associated with TSVD for 3D breast imaging.
• Validation with simulated data, including single and dual lesion models within CT breast geometry, demonstrated the method's effectiveness.

Conclusions:

• The multi-scale mesh strategy provides a viable solution for efficient and accurate TSVD-based DOT reconstruction in 3D breast imaging.
• This approach enhances the practical application of DOT for detecting and characterizing lesions in breast tissue.