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Physics of Photodynamic Therapy

Chapter

Abstract

Photodynamic therapy (PDT) uses light-activated drugs (photosensitizers) for the treatment of neoplastic and non-neoplastic diseases. Administration of the photosensitizer constitutes the first step in the PDT process. Then, following a waiting period (minutes to days) to allow for selective accumulation in the target tissue, the sensitizer is activated via light (usually from a laser) of a wavelength matching a prominent absorption resonance in the red or near-infrared part of the visible spectrum. Absorption of this light by the photosensitizer results in photochemical processes which ultimately produce the cytotoxic species (e.g., singlet molecular oxygen) responsible for the biological damage.

Keywords

Photodynamic therapy Radiation transport Diffusion approximation Monte Carlo simulation PDT dosimetry 

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© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Department of Health Physics and Diagnostic SciencesUniversity of Nevada, Las VegasLas VegasUSA

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