Mueller matrix approach for probing multifractality in the underlying anisotropic connective tissue

Area of Science:

• Biomedical Optics
• Biophysics
• Medical Imaging

Background:

• Connective tissue's spatial refractive index (RI) variation shows multifractality, offering insights into disease morphology.
• Superficial epithelial layers can obscure the underlying connective tissue's multifractal characteristics.

Purpose of the Study:

• To develop and validate a spectral Mueller matrix (MM)-based approach combined with multifractal detrended fluctuation analysis (MFDFA).
• To exclusively identify connective tissue multifractality through superficial layers for disease detection.
• To probe precancer-related ultrastructural alterations in intact tissues.

Main Methods:

• Utilized inverse analysis on spectral scattering MM elements encoding birefringence.
• Applied Born approximation-based Fourier domain preprocessing to extract ultrastructural RI fluctuations.
• Analyzed RI fluctuations using MFDFA to obtain multifractal tissue parameters.
• Validated the method on a tissue model with TiO2 and rat tail collagen.

Main Results:

• Successfully extracted ultrastructural RI fluctuations from anisotropic connective tissue.
• Demonstrated the capability to yield multifractal tissue parameters via MFDFA.
• Validated the method's efficacy on a layered tissue model.
• Showcased the potential for detecting precancer-related changes in connective tissue multifractality.

Conclusions:

• The developed spectral MM and MFDFA approach can effectively probe connective tissue multifractality.
• This method allows for the detection of subtle, precancer-related ultrastructural alterations in intact tissues.
• The technique holds promise for non-invasive diagnostics and disease monitoring.