title: Comparison of three light doses in the photodynamic treatment of actinic keratosis using mathematical modeling.
abstract: Photodynamic therapy (PDT) is an emerging treatment modality for various diseases, especially for cancer therapy. Although high efficacy is demonstrated for PDT using standardized protocols in nonhyperkeratotic actinic keratoses, alternative light doses expected to increase efficiency, to reduce adverse effects or to expand the use of PDT, are still being evaluated and refined. We propose a comparison of the three most common light doses in the treatment of actinic keratosis with 5-aminolevulinic acid PDT through mathematical modeling. The proposed model is based on an iterative procedure that involves determination of the local fluence rate, updating of the local optical properties, and estimation of the local damage induced by the therapy. This model was applied on a simplified skin sample model including an actinic keratosis lesion, with three different light doses (red light dose, 37 J∕cm2, 75 mW∕cm2, 500 s; blue light dose, 10 J∕cm2, 10 mW∕cm2, 1000 s; and daylight dose, 9000 s). Results analysis shows that the three studied light doses, although all efficient, lead to variable local damage. Defining reference damage enables the nonoptimal parameters for the current light doses to be refined and the treatment to be more suitable.
authors.affiliation: INSERM, U1189, ONCO-THAI, 1, avenue Oscar Lambret, F-59037 Lille Cedex, France.
authors.forename: Anne-Sophie
authors.initials: AS
authors.lastname: Vignion-Dewalle
authors.affiliation: INSERM, U1189, ONCO-THAI, 1, avenue Oscar Lambret, F-59037 Lille Cedex, FrancebUniversity of Lille Nord de France, 365 bis, rue Jules Guesde, BP 50458, F-59658 Villeneuve d'Ascq Cedex, France.
authors.forename: Nacim
authors.initials: N
authors.lastname: Betrouni
authors.affiliation: INSERM, U1189, ONCO-THAI, 1, avenue Oscar Lambret, F-59037 Lille Cedex, France.
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Tylcz
authors.affiliation: INSERM, U1189, ONCO-THAI, 1, avenue Oscar Lambret, F-59037 Lille Cedex, FrancebUniversity of Lille Nord de France, 365 bis, rue Jules Guesde, BP 50458, F-59658 Villeneuve d'Ascq Cedex, FrancecCHRU de Lille, Hôpital Huriez, Service Dermatologie, 2, avenue.
authors.forename: Maximilien
authors.initials: M
authors.lastname: Vermandel
authors.affiliation: INSERM, U1189, ONCO-THAI, 1, avenue Oscar Lambret, F-59037 Lille Cedex, FrancebUniversity of Lille Nord de France, 365 bis, rue Jules Guesde, BP 50458, F-59658 Villeneuve d'Ascq Cedex, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Mortier
authors.affiliation: INSERM, U1189, ONCO-THAI, 1, avenue Oscar Lambret, F-59037 Lille Cedex, FrancebUniversity of Lille Nord de France, 365 bis, rue Jules Guesde, BP 50458, F-59658 Villeneuve d'Ascq Cedex, France.
authors.forename: Serge
authors.initials: S
authors.lastname: Mordon
mesh_terms: D000622:Aminolevulinic Acid / Q000008:administration & dosage*; D003198:Computer Simulation; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D055623:Keratosis, Actinic / Q000188:drug therapy* / Q000503:physiopathology*; D008027:Light; D008954:Models, Biological; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000008:administration & dosage; D011829:Radiation Dosage; D012867:Skin / Q000187:drug effects / Q000503:physiopathology* / Q000528:radiation effects; D013813:Therapy, Computer-Assisted / Q000379:methods; D016896:Treatment Outcome
chemical_list: D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid