UV-induced autofluorescence spectroscopy in Barrett's esophagus

Preliminary results of clinical experiments using UV induced autofluorescence spectroscopy in 23 patients with Barrett's esophagus are reported in this paper. Excitation wavelengths of 351 nm and 330 nm were used to induce Barrett's mucosa autofluorescence. Autofluorescence acquisition and signal processing were performed using a CP200 Jobin-Yvon system coupled to a flexible three optical fiber sensor. Three distinct emission bands were observed in the measured spectra after normalization according to the backscattered light power. These emissions were attributed to collagen, elastin, NADH and flavin. Fluorescence intensities and ratios between the emission bands were used to discriminate high grade dysplasia and early stage cancer in Barrett's esophagus from normal surrounding tissues. A significant decrease of the overall fluorescence intensity was observed for the Barrett's mucosa compared to the normal esophageal one. Autofluorescence spectral shape was modified. Collagen and elastin contribution was found to decrease going from normal to tumoral tissue.