FLUORESCENT DIFFUSE PHOTON - DENSITY WAVES IN HOMOGENEOUS AND HETEROGENEOUS TURBID MEDIA - ANALYTIC SOLUTIONS AND APPLICATIONS

We present analytic solutions for fluorescent, diffuse photon density waves originating from fluorophores distributed in thick turbid media. Solutions are derived for a homogeneous turbid medium containing a un iform distribution of fluorophores and for a system that is homogeneou s except for the presence of a single spherical inhomogeneity. General ly the inhomogeneity has fluorophore concentration, and lifetime and o ptical properties that differ from those of the background. The analyt ic solutions are verified by numerical calculations and are used to de termine the fluorophore lifetime and concentration changes required fo r the accurate detection of inhomogeneities in biologically relevant s ystems. The relative sensitivities of absorption and fluorescence meth ods are compared. (C) 1996 Optical Society of America