Fluorescence spectra of normal and atherosclerotic human aorta: Optimum discriminant analysis

To evaluate the usefulness of tissue fluorescence to distinguish normal from atherosclerotic regions in human arteries, we examined fluorescence spectral maps obtained over a wide range of excitation and emission wavelengths from 15 normal and 26 atherosclerotic human aorta specimens. After defining criteria to maximize safety, ease of use, reproducibility and predictive accuracy, we derived an optimum fluorescence discriminant function from this data set which reliably identifies normal and diseased arterial tissue, is independent of sampling device characteristics and vessel geometry, and utilizes simple, available methodologies. This discriminant function, the ratio of fluorescence intensity emitted at 380 nm to that emitted at 420 nm with excitation wavelength of 360 nm [I₃₈₀/I₄₂₀)₃₆₀] compared favorably to other fluorescent discrimination techniques previously described.