Frequency-domain Inverse Monte Carlo Simulation for the Diagnosis of the Early Cervical Cancer Based on NIR Diffuse Measurement

Measurement of near infrared diffuse light on frequency domain is a new technology for the diagnosis of early cervical cancer.Concerning the structure of the cervix,Monte-Carlo simulation(MC) has to be adopted for describing the photon migration in tissue.This article deals with the optical property reconstruction based on MC,especially with the extraction of frequency domain information from the time-domain MC and the retrenchment of the reconstruction time.In extracting the frequency domain information,in addition to the traditional discrete Fourier Transform method,an improved method is developed for reducing the reconstruction error.In order to shorten the computation time,MC simulation databases under a range of scattering coefficients were pre-built and combined with Lagrange interpolation and Lambert-Beer's Law for rapidly obtaining the MC simulation in any optical properties.Reconstruction results from simulated data showed that the improved method has the advantages over the traditional one in both the reconstruction accuracy and computation time.The relative error in reconstruction of scattering coefficient and absorption coefficient is less than ±10%.With the rapid reconstruction strategy developed in this article the computation time for reconstructing one set of the optical properties is less than 1min.