Spectroscopic analysis of precancerous and cancerous lesions of the oral cavity

Laser induced fluorescence (LIF) of tissues depends upon their biochemical and histomorphological characteristics. The purpose of our ongoing research work is to characterize laser-induced fluorescence properties of healthy and dysplastic human oral mucosa, correlate the spectroscopic features with histology and develop a diagnostic algorithm for differentiation of normal from dysplastic tissues. Autofluorescence characteristics of 22 normal, dysplastic, and malignant squamous tissues from the oral cavity were measured in vitro with a spectrofluorometer in the excitation range of 250-500 nm and emission range of 350-750 nm. The contour plots obtained from the excitation-emission matrices (EEMs) of the samples showed consistent differences between normal and abnormal tissues. A portable in vivo laser spectrofluorimeter system and multi-fiber spectral probes were then designed and engineered for collecting fluorescence spectra and diffuse white light reflectance in real time in a clinical setting.