Look-up table based Monte Carlo inverse model as a tool to discover liver tumors

Sammanfattning: Diffuse reflectance spectroscopy is a method that allows investigation of the chromophore composition of tissue. The objective is to explore if the composition can be used to determine whether the tissue is healthy or not. The measured diffuse reflectance is often modelled by a diffusion model. However, the diffusion model has some shortcomings, and therefore this project uses a Monte Carlo model to analyse the measured spectrum. In this thesis a look-up table based Monte Carlo inverse model is developed and compared to a diffusion model for measurements of ex vivo animal liver, in vivo human liver and measurements that investigate the effect of the probe pressure on the chromophore composition. The results show that the Monte Carlo model is a promising method, but in its present form in need of some improvements. The pressure measurements show that a higher pressure results in increased diffuse reflectance. This can be explained by the result of the MC model, but since there are only few studies in this area with contradictory results, no solid conclusions can be drawn from this study.