Share Email Print

Journal of Biomedical Optics

Multiphoton fluorescence lifetime contrast in deep tissue imaging: prospects in redox imaging and disease diagnosis
Author(s): Venkata Krishnan Ramanujan; Jian-Hua Zhang; Eva Biener; Brian A. Herman
Format Member Price Non-Member Price
PDF $20.00 $25.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Turbid tissues pose serious problems of strong absorption and scattering that make steady state fluorescence imaging methods less successful in imaging tissue layers deeper than a few tens of micrometers. Complications arise as one progresses from imaging cells to tissues to whole animal—which include enormous autofluorescence background in tissues and poor signal from regions of interest. Since the steady state, intensity-based methods cannot discriminate the photons arising from the fluorophores and the autofluorescence background, it is almost impractical to isolate these two signals. We describe multiphoton fluorescence lifetime imaging methods in the time domain to demonstrate fluorescence lifetime contrast in discriminating autofluorescence background from the fluorescent signals. Since the photophysical schemes of the fluorophore and autofluorescence contributions are distinct, it is feasible to isolate these two contributions in every pixel based only on their decay constants without compromising the SNR. We present preliminary lifetime measurements to characterize autofluorescence in various cell lines and ex vivo tissues obtained from mouse models. Together, these results suggest a novel direction in obtaining quantitative information from endogenous tissue fluorescence without any exogenous staining. The prospects for this approach in metabolic redox imaging and disease diagnosis are discussed.

Paper Details

Date Published: 1 September 2005
PDF: 11 pages
J. Biomed. Opt. 10(5) 051407 doi: 10.1117/1.2098753
Published in: Journal of Biomedical Optics Volume 10, Issue 5
Show Author Affiliations
Venkata Krishnan Ramanujan, The Univ. of Texas Health Science Ctr. at San Antonio (United States)
Jian-Hua Zhang, The Univ. of Texas Health Science Ctr. at San Antonio (United States)
Eva Biener, The Univ. of Texas Health Science Ctr. at San Antonio (United States)
Brian A. Herman, The Univ. of Texas Health Science Ctr. at San Antonio (United States)

© SPIE. Terms of Use
Back to Top