Optical local and superficial probing of tissues for in vivo diagnosis

摘要

An optical tissue diagnosis technique, often called "optical biopsy", has been developed, It is based on the simultaneous determination of the optical properties of tissues such as the reduced scattering coefficient μ_s' and the absorption coefficient μ_a. These data are obtained by applying a small diameter probe (φ 2mm) on tissues, through the working channel of usual endoscopes. The simultaneous determination of μ_a and μ_s' with a local probe was made possible by the consideration of the first two moments of the phase function and a proven model of light propagation in tissues at propagation length comparable to the scattering mean free path. Non-invasive measurements of the optical coefficients of superficial tissues have been obtained in vivo at different wavelength.