Impact of scattering phase function and polarization on the accuracy of diffuse and sub-diffuse spatial frequency...

Area of Science:

• Biomedical Optics
• Optical Imaging
• Tissue Optics

Background:

• Spatial Frequency Domain Imaging (SFDI) is established for diffuse optical conditions.
• Sub-diffuse SFDI measurements offer potential for novel diagnostic information.
• Assessing sub-diffuse SFDI behavior is crucial for clinical relevance.

Purpose of the Study:

• To characterize the impact of scattering phase function (SPF) and light polarization on SFDI-derived optical properties.
• To evaluate SFDI accuracy under diffuse and sub-diffuse conditions.
• To determine optimal SPF and polarization combinations for accurate measurements.

Main Methods:

• SFDI accuracy was assessed using optical phantoms at four wavelengths (395-850 nm) and two spatial frequencies.
• Three different SPFs and two polarization states (unpolarized, cross-polarized) were utilized.
• The study evaluated SFDI performance under a range of diffuse and sub-diffuse conditions.

Main Results:

• The assumed SPF significantly impacts SFDI-derived optical property accuracy.
• Unpolarized SFDI accuracy improved with a full SPF (forward and backscattering).
• Cross-polarized SFDI accuracy improved with a forward-scattering SPF, mitigating backscattering.

Conclusions:

• Optimal SPF selection is dependent on the light polarization state.
• Accurate optical property derivation is achievable by pairing appropriate SPF and polarization.
• These findings support advanced SFDI applications in sub-diffuse regimes and high spatial frequencies.