Optical sectioning using a fiber probe with an angled illumination-collection geometry: evaluation in engineered...

Area of Science:

• Biomedical Optics
• Optical Diagnostics
• Cancer Research

Background:

• Epithelial precancer detection relies on identifying cellular and tissue microstructure changes.
• Accurate measurement of scatterer size and distribution is vital for early cancer diagnosis.
• Existing optical methods face challenges in specificity and depth resolution within tissues.

Purpose of the Study:

• To develop and validate a fiber optic probe for precise measurement of size-dependent scattering in epithelium.
• To enable the extraction of scatterer size and distribution for precancer detection.
• To assess the probe's performance in tissue phantoms and in vivo.

Main Methods:

• Utilized a fiber optic probe with polarized illumination and detection.
• Employed an angled distal probe geometry for targeted depth analysis.
• Applied Mie theory for analyzing scattering signals to determine scatterer size and distribution.
• Validated the probe using tissue phantoms (polystyrene beads/collagen, cancer cells/collagen) and in vivo oral cavity measurements.

Main Results:

• The fiber optic probe successfully detected size-dependent scattering at specific epithelial depths.
• Mie theory analysis accurately extracted scatterer size and distribution from scattering spectra.
• In vivo measurements in normal volunteers demonstrated correspondence between extracted and independently measured scatterer sizes.
• The probe showed reliable performance in both phantom and in vivo settings.

Conclusions:

• The developed fiber optic probe is effective for quantifying epithelial scatterer size and distribution.
• This technique holds significant potential for non-invasive precancer detection.
• The findings support the clinical utility of optical scattering analysis for early cancer diagnostics.