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Applied Optics

Applied Optics


  • Vol. 37, Iss. 31 — Nov. 1, 1998
  • pp: 7168–7183

Modeling of photosensitizer fluorescence emission and photobleaching for photodynamic therapy dosimetry

Thomas J. Farrell, Robert P. Hawkes, Michael S. Patterson, and Brian C. Wilson  »View Author Affiliations

Applied Optics, Vol. 37, Issue 31, pp. 7168-7183 (1998)

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Photon diffusion theory was used to model photobleaching and tissue necrosis resulting from broad-beam therapeutic light irradiation of tissue containing a photosensitizer. The photosensitizer fluorescence signal at the tissue surface was simulated with both broad-beam and pencil-beam excitation. The relationship between the decreasing fluorescence signal and the increasing depth of tissue photodynamic damage during treatment was examined. By analyzing spatially resolved fluorescence measured at the tissue surface in terms of an equivalent virtual point or planar source of fluorescence within the tissue, predictions of necrosis depth that are insensitive to a range of initial treatment parameters were shown to be possible. Preliminary measurements in tissue-simulating phantoms supported the main theoretical findings. The potential value and feasibility of this technique for photodynamic therapy dosimetry are discussed.

© 1998 Optical Society of America

OCIS Codes
(170.5180) Medical optics and biotechnology : Photodynamic therapy
(170.5280) Medical optics and biotechnology : Photon migration
(170.6280) Medical optics and biotechnology : Spectroscopy, fluorescence and luminescence

Original Manuscript: February 24, 1998
Revised Manuscript: May 14, 1998
Published: November 1, 1998

Thomas J. Farrell, Robert P. Hawkes, Michael S. Patterson, and Brian C. Wilson, "Modeling of photosensitizer fluorescence emission and photobleaching for photodynamic therapy dosimetry," Appl. Opt. 37, 7168-7183 (1998)

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