Perturbation theory for the refractive index mismatch between the inclusion and the surrounding tissues

AbstractTissue refractive index is one optical contrast mechanism with diagnostic potential, it is very important to investigate the effect of the refractive index mismatch on light propagation through diffusive regions. Here, we present a new analytical solution of perturbation theory for the refractive index mismatch between the small spherical inclusion and the surrounding tissues. The solution has been used to implement fitting procedures in order to obtain the optical properties of a heterogeneous sphere in semi-infinite medium from measurements of diffuse reflectance. Finally, perturbation theory has been validated by comparisons with the results of Monte Carlo simulation. The new perturbation theory would provide a basis for allowing early disease diagnosis and automatic screening.