title: Evaluation of LiF:Mg,Ti (TLD-100) for Intraoperative Electron Radiation Therapy Quality Assurance.
abstract: BACKGROUND
  Purpose of the present work was to investigate thermoluminescent dosimeters (TLDs) response to intraoperative electron radiation therapy (IOERT) beams. In an IOERT treatment, a large single radiation dose is delivered with a high dose-per-pulse electron beam (2-12 cGy/pulse) during surgery. To verify and to record the delivered dose, in vivo dosimetry is a mandatory procedure for quality assurance. The TLDs feature many advantages such as a small detector size and close tissue equivalence that make them attractive for IOERT as in vivo dosimeters.
  
  
  METHODS
  LiF:Mg,Ti dosimeters (TLD-100) were irradiated with different IOERT electron beam energies (5, 7 and 9 MeV) and with a 6 MV conventional photon beam. For each energy, the TLDs were irradiated in the dose range of 0-10 Gy in step of 2 Gy. Regression analysis was performed to establish the response variation of thermoluminescent signals with dose and energy.
  
  
  RESULTS
  The TLD-100 dose-response curves were obtained. In the dose range of 0-10 Gy, the calibration curve was confirmed to be linear for the conventional photon beam. In the same dose region, the quadratic model performs better than the linear model when high dose-per-pulse electron beams were used (F test; p<0.05).
  
  
  CONCLUSIONS
  This study demonstrates that the TLD dose response, for doses ≤10 Gy, has a parabolic behavior in high dose-per-pulse electron beams. TLD-100 can be useful detectors for IOERT patient dosimetry if a proper calibration is provided.
authors.affiliation: Institute of Biostructure and Bioimaging, National Research Council (CNR), Naples, Italy.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Liuzzi
authors.affiliation: Department of Physics, Federico II University, Naples, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Savino
authors.affiliation: Institute of Biostructure and Bioimaging, National Research Council (CNR), Naples, Italy.
authors.forename: Vittoria
authors.initials: V
authors.lastname: D'Avino
authors.affiliation: Department of Physics, Federico II University, Naples, Italy.
authors.forename: Mariagabriella
authors.initials: M
authors.lastname: Pugliese
authors.affiliation: Institute of Biostructure and Bioimaging, National Research Council (CNR), Naples, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Cella
mesh_terms: D001918:Brachytherapy / Q000379:methods*; D004583:Electrons; D005459:Fluorides / Q000737:chemistry*; D006801:Humans; D018020:Lithium Compounds / Q000737:chemistry*; D008274:Magnesium / Q000737:chemistry*; D009010:Monte Carlo Method; D011786:Quality Control; D013819:Thermoluminescent Dosimetry / Q000295:instrumentation / Q000379:methods*; D014025:Titanium / Q000737:chemistry*
chemical_list: D018020:Lithium Compounds; C027651:lithium fluoride; D014025:Titanium; D008274:Magnesium; D005459:Fluorides