FLUORESCENCE IMAGING SYSTEM AND METHOD

A system and method non-invasive biomedical optical imaging and spectroscopy with low-level light is described. The technique consists of a modulated light source (120) coupled to tissue (100) of a patient to introduce excitation light. Fluorescent light emitted in response to the excitation light is detected with sensor (148). The AC intensity and phase of the excitation and detected fluorescent light is provided to a processor (160) operatively coupled to sensor (148). Processor (160) employs the measured re-emission kinetics of excitation and fluorescent light to "map" the spatial variation of one or more fluorescence characteristics of the tissue (100). The fluorescence characteristic may be provided by exogenous contract agents, endogenous fluorophores, or both. The variation is determined by solving frequency domain diffusion equations at a number of designated points in the tissue as part of a recursive estimation algorithm. Processor (160) generates an imaging signal in accordance with the spatial variation of the fluorescence characteristic for provision to an output device (164). The output device (164) displays an image corresponding spatial variation of the fluorescence characteristic which corresponds to tissue (100) to aid in the detection and diagnosis of disease.