The Primary Study Of Controlling Tissue Optical Properties Quantitatively

The invention of tissue optical clearing has led to a turning point for further development of photonics industry in terms of medical imaging technologies and diagnostics. It has been studied much that the optical clearing agents can decrease the scattering properties of bio-tissue and enhance the penetration depth of light into it. However, few people have tried to describe this effect quantitatively and put it in use. This study tries to build a method of determining the change of skin optical properties resulting from the use of optical clearing agents quantitatively.With the deep analyses of skin structure and the barrier function of stratum corneum, this study has built a Diffusion Model (DM) and a seven-layer optical Monte Carlo Model (MCM) by simplifying the courses of saturation of optical clearing agents through skin and the change of skin optical properties. The models have been validated by the experiment with porcine skin in vitro and Monte Carlo simulation. The results indicated that the DM can predict the osmotic trends of optical agents into skin to a great degree. The MCM Method can simulate the degree of change of skin optical properties when optical clearing agents immerse into different layers of skin, which is coherent with the experimental results.We defined an index as the matching degree of refractive indices to evaluate the change of penetrating ability of light into skin because of optical clearing agents, which is proved to be successful(the correlation coefficient equals to 0.993). In the end, we gave the protocol about how to select optical clearing agents for clinical use.The thesis primarily investigated how to quantitatively control the change of the optical properties of skin topically applied with optical clearing agents, which can be used to estimate the optical clearing effect of skin with optical clearing agents. It can be also used to control the optical properties of skin quantitatively.