Fiber based in-vivo imaging of epithelial FAD fluorescence: experiments and simulations

Abstract

Fluorescence from endogenous fluorophores has been emerging as a promising biomarker for tissue discrimination resulting a noninvasive screening methodology to understand the biochemical and morphological variations in tissues associated with cancer development. We have developed a scan based fiber optic probe system to image increased flavin adenine dinucleotide (FAD) fluorescence from epithelial tissues under conditions mimicking dysplasia surrounded by normal tissues. Experiments were conducted on optical phantoms mimicking epithelial tissues excited by 450nm LED source. The spectral emission from the sample is collected via optical fibers and the imaging is performed by scanning the sample using a translation stage at desired resolution. Monte Carlo simulations were also performed by devising an optical model corresponding to epithelial tissue and the results were correlated with experimental fluorescence measurements. This whole field imaging approach could be useful for in vivo assessment of tissue pathologies based on auto fluorescence and can give a better quantitative approach for estimation of tissue properties by correlating the experimental and simulated data.

Model-based quantitative optical biopsy in multilayer in vitro soft tissue models for whole field assessment of nonmelanoma skin cancer

“…Spectral data of the specified biomarkers namely FAD, collagen, and Hb in the phantom sample were collected at each sample positions by raster scanning using the automated scan-based spectral imaging setup. Acquired data were processed and enhanced using a suitable algorithm 41,42 to generate the intended fluorescence and reflectance image of the biomarkers highlighting the normal and abnormal regions of sample as shown in Figs. 6(a)-6(d).…”