[Analysis of Optical Coherence Tomography Based on Monte Carlo Simulation Model].

Area of Science:

• Biomedical Optics
• Medical Imaging
• Computational Modeling

Background:

• Optical coherence tomography (OCT) is a vital non-invasive imaging technique.
• Accurate modeling of light propagation in human skin is crucial for OCT.
• Existing models may not fully capture the complexities of multi-layer skin tissue.

Purpose of the Study:

• To develop an advanced Monte Carlo model for OCT simulations in human skin.
• To incorporate an importance sampling technique tailored for multi-layer skin.
• To analyze Gaussian beam focusing and OCT detection depth in skin.

Main Methods:

• Developed a novel Monte Carlo simulation incorporating importance sampling for multi-layer skin.
• Introduced new rules for classifying back-scattered photons.
• Simulated Gaussian beam propagation and analyzed OCT parameters.

Main Results:

• The simulation confirmed focus distortion (shift and diffusion) of Gaussian beams in skin.
• Higher numerical aperture (NA) of objective lenses was found to reduce the maximum OCT detecting depth.
• The model accurately represents light-matter interactions in skin.

Conclusions:

• The proposed Monte Carlo model provides a robust tool for OCT simulation in human skin.
• Understanding focus distortion is key to optimizing OCT imaging parameters.
• Lens NA is a critical factor influencing OCT penetration depth in skin.