An analytical solution is developed to quantify a site-specific fluorophore lifetime perturbation that occurs, for example, when the local metabolic status is different from that of surrounding tissue. This solution may be used when fluorophores are distributed throughout a highly turbid media and the site of interest is embedded many mean scattering distances from the source and the detector. The perturbation in lifetime is differentiated from photon transit delays by random walk theory. This analytical solution requires <i>a priori</i> knowledge of the tissue-scattering and absorption properties at the excitation and emission wavelengths that may be obtained from concurrent time-resolved reflection measurements. Additionally, the solution has been compared with the exact, numerically solved solution. Thus the presented solution forms the basis for practical lifetime imaging in turbid media such as tissue.
© 2001 Optical Society of America
(170.3650) Medical optics and biotechnology : Lifetime-based sensing
(170.5280) Medical optics and biotechnology : Photon migration
(170.6280) Medical optics and biotechnology : Spectroscopy, fluorescence and luminescence
David Hattery, Victor Chernomordik, Murray Loew, Israel Gannot, and Amir Gandjbakhche, "Analytical solutions for time-resolved fluorescence lifetime imaging in a turbid medium such as tissue," J. Opt. Soc. Am. A 18, 1523-1530 (2001)