Quantitative imaging by a newly developed endoscopic system for pathological malignancy status based on endogenous fluorescence

We found that a nitrosamine-induced esophageal tumor model rat showed the endogenous fluorescence correlated to the pathological status. Fluorometric analysis revealed that the endogenous fluorescence with a peak of 630 nm (excitation: 405nm) is seen in the areas where atypical cells exist, and intensity of the fluorescence was positively correlated with the time period of nitrosamine administration. High performance liquid chromatography revealed that an origin of the endogenous fluorescence is protoporphyrin IX. Hence, we established an imaging technique for evaluation of the pathological status with the endogenous fluorescence as a clue. The constructed imaging system was composed of an endoscope-based fluorescence multispectral imaging (FMSI) system equipped with a spectral unmixing unit. The novel endoscopic system enabled us to detect early lesions by transesophageal approach. The newly developed endoscope-based FMSI system can be a promising tool for the detection of precancerous lesions based on endogenous fluorescence. © 2014, Japan Soc. of Med. Electronics and Biol. Engineering. All rights reserved.