title: A feasibility study of singlet oxygen explicit dosmietry (SOED) of PDT by intercomparison with a singlet oxygen luminescence dosimetry (SOLD) system.
abstract: An explicit dosimetry model has been developed to calculate the apparent reacted1O2concentration ([1O2]rx) in anin-vivomodel. In the model, a macroscopic quantity,g, is introduced to account for oxygen perfusion to the medium during PDT. In this study, the SOED model is extended for PDT treatment in phantom conditions where vasculature is not present; the oxygen perfusion is achieved through the air-phantom interface instead. The solution of the SOED model is obtained by solving the coupled photochemical rate equations incorporating oxygen perfusion through the air-liquid interface. Experiments were performed for two photosensitizers (PS), Rose Bengal (RB) and Photofrin (PH), in solution, using SOED and SOLD measurements to determine both the instantaneous [1O2] as well as cumulative [1O2]rxconcentrations, where [1O2]rx= (1/τΔ) · ∫[1O2]dt. The PS concentrations varied between 10 and 100 mM for RB and ~200 mM for Photofrin. The resulting magnitudes of [1O2] were compared between SOED and SOLD.
authors.affiliation: Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA; Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Michele M
authors.initials: MM
authors.lastname: Kim
authors.affiliation: Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Rozhin
authors.initials: R
authors.lastname: Penjweini
authors.affiliation: Department of Electronic and Nanoscale Engineering, University of Glasgow, UK.
authors.forename: Nathan R
authors.initials: NR
authors.lastname: Gemmell
authors.affiliation: Princess Margaret Cancer Centre, University of Toronto, Canada.
authors.forename: Israel
authors.initials: I
authors.lastname: Veilleux
authors.affiliation: Institute of Photonics and Quantum Sciences, Heriot-Watt University, UK.
authors.forename: Aongus
authors.initials: A
authors.lastname: McCarthy
authors.affiliation: Institute of Photonics and Quantum Sciences, Heriot-Watt University, UK.
authors.forename: Gerald
authors.initials: G
authors.lastname: Buller
authors.affiliation: Department of Electronic and Nanoscale Engineering, University of Glasgow, UK.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Hadfield
authors.affiliation: Princess Margaret Cancer Centre, University of Toronto, Canada.
authors.forename: Brian C
authors.initials: BC
authors.lastname: Wilson
authors.affiliation: Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Timothy C
authors.initials: TC
authors.lastname: Zhu
keywords: PDT; SOED; SOLD; explicit PDT dosimetry; photodynamic therapy; singlet oxygen