title: Comparison of calculated dose by helical tomotherapy treatment planning machine and measured dose of radiophotoluminescence glass dosimeter in lung lesions using Rando Phantom.
abstract: OBJECTIVE
  To examine the compatibility of the measured and calculated dose for the treatment of lung lesions by helical tomotherapy.
  
  
  METHODS
  The administered dose was measured a total of 55 times at 22 points with a radiophotoluminescence glass dosimeter (RPLGD) inserted in the position of an anthropomorphic Rando Phantom. Two Gy were prescribed and calculated with a tomotherapy planning machine for a 3-cm diameter spherical planning target volume (PTV) created in the lung area. Compatibility (measured dose/calculated dose and σ value=(D(meas)-D(calc))/D(prescribed)) × 100 (%)) was analyzed according to dosimeter location.
  
  
  RESULTS
  Deviations between measured and calculated doses for the lung lesion were within 4% for planning target volume, indicating that adequate dose delivery to the PTV was achievable. On the other hand, we found dose deviations up to 15% for the lower prescribed dose range (64% or less) for the measured dose/calculated comparison and a 6% deviation according to the σ value in or near inhomogeneous tissue.
  
  
  CONCLUSIONS
  Although the measured dose satisfied the clinical requirement in almost all areas including PTV, we should note that there may be discrepancies between expected calculated dose and irradiated dose in or near inhomogeneous area.
authors.affiliation: Department of Radiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto, Japan. hideya10@hotmail.com
authors.forename: Hideya
authors.initials: H
authors.lastname: Yamazaki
authors.forename: Kazuki
authors.initials: K
authors.lastname: Iwama
authors.forename: Takuya
authors.initials: T
authors.lastname: Nishimura
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Iwai
authors.forename: Norihiro
authors.initials: N
authors.lastname: Aibe
authors.forename: Tadashi
authors.initials: T
authors.lastname: Takenaka
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Miyake
authors.forename: Eiichi
authors.initials: E
authors.lastname: Tanaka
authors.forename: Ken
authors.initials: K
authors.lastname: Yoshida
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Oota
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Ikeno
authors.forename: Satoakai
authors.initials: S
authors.lastname: Nakamura
authors.forename: Haruumi
authors.initials: H
authors.lastname: Okabe
mesh_terms: D000328:Adult; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000532:radiotherapy*; D019047:Phantoms, Imaging; D011834:Radiation Monitoring / Q000295:instrumentation* / Q000379:methods; D011880:Radiotherapy Planning, Computer-Assisted; D050397:Radiotherapy, Intensity-Modulated; D013819:Thermoluminescent Dosimetry