Improvement of the frequency-domain inverse Monte Carlo simulation

This article aims at the optical property (absorption coefficient and scatter coefficient) reconstruction from the frequency-domain (FD) near-infrared diffuse measurement on small tissues, such as a cervix, for which inverse Monte Carlo (MC) simulation is the suitable choice. To achieve the fast and accurate reconstruction based on the inverse Monte Carlo simulation, following techniques were adopted. First, in the forward calculation, a database, which include the frequency-domain information calculated from MC simulation for a series of optical parameters of tissue, were established with fast methods. Then, in the reconstruction procedure, Levenberg-Marquardt (L-M) optimization was adopted and Multiple Polynomial Regression (MPR) method was used to rapidly get the FD information at any optical properties by best fitting the curved surface formed by the above database. At Last, in the reconstruction, to eliminate the influence of the initial guess of optical properties on the reconstruction accuracy, cluster analysis method was introduced into L-M reconstruction algorithm to determine the region of the initial guess. The reconstruction algorithm was demonstrated with simulation data. The results showed that it takes less than 0.5s to reconstruction one set of optical properties. The average relative error from the reconstruction algorithm joined with cluster analysis is 10% lower than that without cluster analysis.