Article

Endoscopic fluorescence spectroscopy in the upper GI tract for the detection of GI cancer: Initial experience

Department of Medicine I, University of Erlangen-Nuremberg, Erlangen, Germany.
The American Journal of Gastroenterology (Impact Factor: 9.21). 10/2001; 96(9):2616-21. DOI: 10.1111/j.1572-0241.2001.04122.x
Source: PubMed

ABSTRACT The aim of this study was to investigate autofluorescence spectroscopy using violet-blue excitation light for the in vivo diagnosis of GI cancer during routine endoscopy.
Fluorescence spectra were obtained from normal mucosa and cancerous lesions of the esophagus and stomach. The spectroscopic system used comprised a special light source capable of delivering either white or violet-blue light to induce autofluorescence of tissue via the endoscope. Endogenous fluorescence spectra emitted by the tissue were recorded with a fiberoptic probe and analyzed with a spectrographic detector system consisting of a polychromator with a photodiode array and an optical multichannel analyzer. The data of each spectrum were sampled within the range of 450-700 nm and stored in a personal computer.
Esophageal squamous cell cancer, adenocarcinoma of the esophagus, and adenocarcinoma of the stomach show specific differences in the emitted fluorescence spectra compared with normal mucosa.
Light-induced fluorescence spectroscopy might be a useful tool for the endoscopic in vivo detection of dysplasia and early carcinoma in the upper GI tract. Further trials are needed to test the validity of this new optical detection system.

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