title: Polyethylene Naphthalate Scintillator: A Novel Detector for the Dosimetry of Radioactive Ophthalmic Applicators.
abstract: BACKGROUND
  Dosimetric measurements in small radiation fields with large gradients, such as eye plaque dosimetry with β or low-energy photon emitters, require dosimetrically almost water-equivalent detectors with volumes of <1 mm(3) and linear responses over several orders of magnitude. Polyvinyltoluene-based scintillators fulfil these conditions. Hence, they are a standard for such applications. However, they show disadvantages with regard to certain material properties and their dosimetric behaviour towards low-energy photons.
  Polyethylene naphthalate, recently recognized as a scintillator, offers chemical, physical and basic dosimetric properties superior to polyvinyltoluene. Its general applicability as a clinical dosimeter, however, has not been shown yet. To prove this applicability, extensive measurements at several clinical photon and electron radiation sources, ranging from ophthalmic plaques to a linear accelerator, were performed.
  
  
  RESULTS
  For all radiation qualities under investigation, covering a wide range of dose rates, a linearity of the detector response to the dose was shown.
  
  
  CONCLUSIONS
  Polyethylene naphthalate proved to be a suitable detector material for the dosimetry of ophthalmic plaques, including low-energy photon emitters and other small radiation fields. Due to superior properties, it has the potential to replace polyvinyltoluene as the standard scintillator for such applications.
authors.affiliation: Universitätsklinikum Essen, Essen, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Flühs
authors.affiliation: Universitätsklinikum Essen, Essen, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Flühs
authors.affiliation: Universitätsklinikum Essen, Essen, Germany; Technische Universität Dortmund, Dortmund, Germany.
authors.forename: Melanie
authors.initials: M
authors.lastname: Ebenau
authors.affiliation: Technische Universität Dortmund, Dortmund, Germany.
authors.forename: Marion
authors.initials: M
authors.lastname: Eichmann
keywords: Dosimetry; Ophthalmic plaque; Polyethylene naphthalate scintillators; Polyvinyltoluene scintillators