Fluorescence excitation emission matrices of human tissue: A system for invivo measurement and method of data analysis

We describe a system capable of measuring spatially resolved reflectance sp ectra from 380 to 950 nm and fluorescence excitation emission matrices from 330 to 500 nm excitation and 380 to 700 nm emission in vivo, system perfor mance was compared to that of a standard scanning spectrofluorimeter. This "FastEEM" system was used to interrogate human normal and neoplastic oral c avity mucosa in vivo. Measurements were made through a fiber-optic probe an d require 4 min total measurement time. We present a method based an autoco rrelation vectors to identify excitation and emission wavelengths where the spectra of normal and pathologic tissues differ most. The FastEEM system p rovides a tool with which to study the relative diagnostic ability of chang es in absorption, scattering, and fluorescence properties of tissue.