The Optical Properties of Tissues and Light Dosimetry at 633 Nanometers

Abstract

<p>The goal of the research presented in this thesis is to improve the state of light dosimetry in tissue. Dosimetry with light at and near a wavelength of 632.8 nanometers will be of primary concern as such light is commonly used in photodynamic therapy, which is an experimental form of cancer treatment.</p> <p>The research described in this thesis was done in three steps. Firstly, in order to determine the regime of optical interaction coefficients appropriate to the problem, the coefficients of representative tissues at 632.8 nm were measured directly: in other words, without using a model of radiation transport in the data analysis. Secondly, in order to ascertain the strengths and weaknesses of two models of radiation transport, calculations from diffusion theory and Monte Carlo theory, of several bulk optical features of tissue-like media, were compared. Finally, the appropriateness of the Monte Carlo method for modelling the propagation of light in tissue was shown by comparing theoretical predictions of fluence and diffuse reflectance in tissue-like phantom media with experimental results.</p>