Hybrid simplified spherical harmonics with diffusion equation for light propagation in tissues

Area of Science:

• Biomedical Optics
• Computational Biology
• Medical Physics

Background:

• Simplified Spherical Harmonics (SPN) and Diffusion Equation (DE) models have limitations in describing light propagation in tissues.
• Accurate modeling of light transport is crucial for various biomedical applications, including imaging and phototherapy.

Purpose of the Study:

• To propose a novel hybrid simplified spherical harmonics with diffusion equation (HSDE) model for diffuse light transport in biological tissues.
• To achieve a balance between accuracy and computational efficiency in light propagation modeling.

Main Methods:

• Segmenting the body into organs and classifying tissues into high scattering and other types.
• Employing DE for high scattering tissues and SPN for other tissues, coupled via boundary conditions.
• Solving the HSDE model using the finite element method to obtain light flux density maps.

Main Results:

• The HSDE model demonstrated comparable accuracy to the SPN model but with significantly reduced computation time.
• Compared to the DE model, the HSDE model achieved substantially improved accuracy.
• Validation was performed using regular geometries and a digital mouse model.

Conclusions:

• The HSDE model effectively combines the strengths of SPN and DE, overcoming their individual limitations.
• This hybrid approach offers a superior balance of accuracy and computational efficiency for diffuse light transport modeling.
• The HSDE model shows promise for advancing biomedical optics and computational modeling in biological systems.