Laser-induced fluorescence spectroscopy of colonic dysplasia: Prospects for optical histological analysis

摘要

Several groups have shown that laser-induced fluorescence spectroscopy can detect dysplastic changes in human colon tissues. We present an approach based on analysis of the underlying tissue microstructure for extracting histological information from such spectral signals. The method employs fluorescence microscopy and tissue optics to model the "bulk" fluorescence collected with an optical fiber probe in a clinical setting. The results are in excellent agreement with average normal colon and adenoma spectra collected during colonoscopy, using 370 nm excitation. Four factors were found to be responsible for the spectral differences between normal tissue and adenoma: fluorescence of mucosal collagen, dysplastic cells, and submucosa; and absorption by hemoglobin. Preliminary results indicate that by reversing the modeling procedure, parameters quantifying these factors can be extracted from individual clinical spectra and correlated to histological features of tissue.