title: Initial investigation of a novel light-scattering gel phantom for evaluation of optical CT scanners for radiotherapy gel dosimetry.
abstract: There is a need for stable gel materials for phantoms used to validate optical computerized tomography (CT) scanners used in conjunction with radiation-induced polymerizing gel dosimeters. Phantoms based on addition of light-absorbing dyes to gelatine to simulate gel dosimeters have been employed. However, to more accurately simulate polymerizing gels one requires phantoms that employ light-scattering colloidal suspensions added to the gel. In this paper, we present the initial results of using an optical CT scanner to evaluate a novel phantom in which radiation-exposed polymer gels are simulated by the addition of colloidal suspensions of varying turbidity. The phantom may be useful as a calibration transfer standard for polymer gel dosimeters. The tests reveal some phenomena peculiar to light-scattering gels that need to be taken into account when calibrating polymer gel dosimeters.
authors.affiliation: Institute of Medical Physics, School of Physics, University of Sydney, NSW 2006, Australia.
authors.forename: Stephen
authors.initials: S
authors.lastname: Bosi
authors.forename: Pourandokht
authors.initials: P
authors.lastname: Naseri
authors.forename: Alicia
authors.initials: A
authors.lastname: Puran
authors.forename: Justin
authors.initials: J
authors.lastname: Davies
authors.forename: Clive
authors.initials: C
authors.lastname: Baldock
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D005780:Gelatin / Q000737:chemistry*; D005782:Gels; D008027:Light; D019047:Phantoms, Imaging; D011134:Polysaccharides / Q000737:chemistry*; D011879:Radiotherapy Dosage; D012542:Scattering, Radiation; D041622:Tomography, Optical / Q000295:instrumentation*
chemical_list: D000447:Aldehydes; D005782:Gels; D011134:Polysaccharides; C413302:poly(aldehyde guluronate); D005780:Gelatin