title: Prevention of transfusion-associated graft-versus-host disease by irradiation: technical aspect of a new ferrous sulphate dosimetric system.
abstract: Irradiation of whole blood and blood components before transfusion is currently the only accepted method to prevent Transfusion-Associated Graft-Versus-Host-Disease (TA-GVHD). However, choosing the appropriate technique to determine the dosimetric parameters associated with blood irradiation remains an issue. We propose a dosimetric system based on the standard Fricke Xylenol Gel (FXG) dosimeter and an appropriate phantom. The modified dosimeter was previously calibrated using a (60)Co teletherapy unit and its validation was accomplished with a (137)Cs blood irradiator. An ionization chamber, standard FXG, radiochromic film and thermoluminescent dosimeters (TLDs) were used as reference dosimeters to determine the dose response and dose rate of the (60)Co unit. The dose distributions in a blood irradiator were determined with the modified FXG, the radiochromic film, and measurements by TLD dosimeters. A linear response for absorbed doses up to 54 Gy was obtained with our system. Additionally, the dose rate uncertainties carried out with gel dosimetry were lower than 5% and differences lower than 4% were noted when the absorbed dose responses were compared with ionization chamber, film and TLDs.
authors.affiliation: Physics Department, School of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo (FFCLRP/USP), Ribeirão Preto, São Paulo, Brazil. lucasdellama@gmail.com
authors.forename: Lucas Sacchini
authors.initials: LS
authors.lastname: Del Lama
authors.forename: Evamberto Garcia
authors.initials: EG
authors.lastname: de Góes
authors.forename: Paulo César Dias
authors.initials: PC
authors.lastname: Petchevist
authors.forename: Edson Lara
authors.initials: EL
authors.lastname: Moretto
authors.forename: José Carlos
authors.initials: JC
authors.lastname: Borges
authors.forename: Dimas Tadeu
authors.initials: DT
authors.lastname: Covas
authors.forename: Adelaide
authors.initials: A
authors.lastname: de Almeida
mesh_terms: D000818:Animals; D002138:Calibration; D004307:Dose-Response Relationship, Radiation; D005296:Ferrous Compounds / Q000494:pharmacology*; D006086:Graft vs Host Disease / Q000209:etiology* / Q000517:prevention & control*; D006801:Humans; D019047:Phantoms, Imaging; D011874:Radiometry / Q000295:instrumentation*; D012015:Reference Standards; D034421:Sus scrofa; D013819:Thermoluminescent Dosimetry; D065227:Transfusion Reaction
chemical_list: D005296:Ferrous Compounds; C020748:ferrous sulfate