Spectroscopic imaging of tissues using micro-endoscopy

Abstract

Recent advances in optics and CCD imaging technology have made possible the advent of small, position sensitive, articulating endoscopes allowing visual access to small cavities within the human body. We present our results for the design, construction and evaluation of a spectrometer capable of measuring molecular fluorescence phenomena as a function of wavelength, position and intensity in small cavities. State-of-the-art micro-endoscope technology is combined with wavelength sorting and CCD imaging to accomplish remote imaging. Presently, images can be magnified by 50x with visual resolution of about 50 LP/mm by direct observation of a USAF resolution target. We detail our biological cell imaging results where a special class of fluorescent molecules (chelate complexes of lathinide (III) polyazamacrocyclic acetates containing pyridine) are introduced into osteosarcoma tissue (a bone cancer tissue). It is shown that the unique molecular site selectivity of the Tb-+3 compound combined with the microendoscopic spectrometer is a useful tool for osteosarcoma rat host investigations in-vivo. We demonstrate that direct observation of the probe molecules in the tissue can yield physiological information regarding interstitial fluid flow in the osteosarcoma tumors.<>