Design and Validation of a Multimodal Diffuse Reflectance and Spatially Offset Raman Spectroscopy System for In Vivo...

Area of Science:

• Biophotonics
• Spectroscopy
• Medical Diagnostics

Background:

• Multimodal spectroscopy offers enhanced tissue analysis by combining different optical techniques.
• Distinguishing superficial from subsurface tissue components is crucial for accurate diagnostics.

Purpose of the Study:

• To develop and evaluate a novel multimodal spectroscopy system integrating diffuse reflectance spectroscopy (DRS) and spatially offset Raman spectroscopy (SORS).
• To assess the system's capability in differentiating superficial and subsurface tissue spectral signatures.

Main Methods:

• Designed a fiber optic probe with spatially offset and ball lens-coupled fibers for both superficial and subsurface measurements.
• Acquired diffuse reflectance spectroscopy (DRS), zero-offset Raman spectroscopy (RS), and spatially offset Raman spectroscopy (SORS) data.
• Validated the system using chicken breast tissue and human volunteer skin measurements.

Main Results:

• Demonstrated that both DRS and RS can acquire spectra from similar depths in chicken breast tissue.
• Identified distinct Raman peaks unique to superficial (ball lens) and subsurface (spatially offset) measurements on human skin.
• Observed melanin-specific Raman peaks in superficial measurements, absent in subsurface data.

Conclusions:

• The developed multimodal system effectively distinguishes between superficial and subsurface tissue optical properties.
• This technology holds promise for non-invasive tissue characterization and diagnostics by leveraging complementary spectroscopic modalities.