Optical Model Of Port Wine Stains And Its Monte Carlo Simulation

Photodynamic Therapy (PDT) is a promising treatment for port wine stains (PWS), a vascular malformation of the skin characterized by overabundant and/or enlarged blood vessels. Light dose for patient-specific structure of PWS lesions is the key for PDT treatment of PWS. In order to study this issue, optical model based on physiological structure of PWS is the foundation. We developed optical Monte Carlo (MC) programs of PWS which can simulate diffuse reflectance spectroscopy, autofluorescence spectroscopy and energy depositions of light in PWS skin. The simulated results of this study provided useful guidelines for selecting optimal light dose in PWS treatment by PDT and estimating of PWS skin by diffuse reflectance-autofluorescence spectroscopy.The thesis was componented of the five parts as follows:1. PWS skin is introduced. The optical Monte Carlo Programs of PWS are reviewed. The problems in present were also pointed out.2. The principles of MC technique, diffuse reflectance spectroscopy and autofluorescence spectroscopy were introduced. And then, author discussed the feasibility of combination of diffuse reflectance spectroscopy and autofluorescence spectroscopy for diagnosis of PWS skin.3. Physiological structure of PWS was described briefly. Then, Two optical model of PWS skin were developed: layer model and cylinder model.4. Energy deposition of light in optical model of PWS was simulated. Impact of diameter of blood vessels, stratum layer and content of melanin to energy deposition were analyzed.5. Diffuse reflectance and autofluorescence spectra were simulated as well. And author discussed the influence of geometry of blood vessels, stratum layer and content of melanin to spectra.