Proceedings of SPIE - the International Society for Optical Engineering
This paper analyzes the short pulse laser propagation through tissues for development of a time-resolved optical tomography system for detection of tumors and inhomogeneities in tissues. Traditional method for analyzing optical transport in tissues is the parabolic or diffusion approximation in which the energy flux is assumed proportional to the fluence (intensity averaged over all solid angles) gradients. The inherent drawback in this model is that it predicts infinite speed of propagation of the optical signal. In this paper accurate hyperbolic or wave nature of transient radiative transfer formulation is used to overcome such drawbacks. The transmitted and reflected intensity distributions are obtained using hyperbolic P1 and discrete ordinates method and the results are compared with the parabolic diffusion P1 approximation. Parametric study of tissue thickness, pulse width, scattering and absorption coefficients of tissues, tumor location, size and properties, and scattering phase function distribution is also performed to analyze their effect on the transmitted and reflected optical signals.
Mitra, K., & Vo-Dinh, T. (2001). Use of short-pulse laser for optical tomography of tissues. Proceedings of SPIE - the International Society for Optical Engineering, 4254, 61-71.