Evaluation of a Gafchromic EBT2 film dosimetry system for radiotherapy quality assurance

This study examines the dosimetric accuracy of Gafchromic EBT2 model radiochromic film for use in radiotherapy quality assurance. In this study, film was scanned using an Epson Perfection V700 flatbed scanner in transmission mode at 75 DPI with the subsequent analysis performed using the red and blue colour channels and ImageJ software. Results of this study suggest that the conversion of film optical density to measured dose should, at present, utilise red channel data only, without application of a blue channel correction to the data. For the batch of film examined here, film uniformity and reproducibility appear to have improved compared with published results using older batches. The orientation of the film on the scanner and the side of the film facing the light source were found to have substantial effects on results. Based on the results of this study, it is possible to recommend the use of EBT2 film in routine quality assurance testing for radiotherapy, in situations where a dose uncertainty of up to 2.8% is acceptable.

[1]  G. K. Bhattacharyya,et al.  Statistics: Principles and Methods , 1994 .

[2]  I. Kawrakow,et al.  On the characterization and uncertainty analysis of radiochromic film dosimetry. , 2009, Medical physics.

[3]  Elisa Calamia,et al.  Clinical use of EBT model Gafchromic™ film in radiotherapy. , 2006, Medical physics.

[4]  Steven D Chang,et al.  The use of TLD and Gafchromic film to assure submillimeter accuracy for image-guided radiosurgery. , 2008, Medical dosimetry : official journal of the American Association of Medical Dosimetrists.

[5]  Patrick A Kupelian,et al.  Characterization and use of EBT radiochromic film for IMRT dose verification. , 2006, Medical physics.

[6]  M. Butson,et al.  Dose and absorption spectra response of EBT2 Gafchromic film to high energy x-rays , 2009, Australasian Physical & Engineering Sciences in Medicine.

[7]  M. Butson,et al.  Post-irradiation colouration of Gafchromic EBT radiochromic film , 2005, Physics in medicine and biology.

[8]  S. Fletcher,et al.  Evaluation and optimization of the new EBT2 radiochromic film dosimetry system for patient dose verification in radiotherapy , 2010, Physics in medicine and biology.

[9]  C Ross Schmidtlein,et al.  Precise radiochromic film dosimetry using a flat-bed document scanner. , 2005, Medical physics.

[10]  Oliver Jäkel,et al.  Technical Note: Homogeneity of Gafchromic® EBT2 film , 2010 .

[11]  L. V. van Battum,et al.  Accurate dosimetry with GafChromic EBT film of a 6 MV photon beam in water: what level is achievable? , 2008, Medical physics.

[12]  E. Wilcox,et al.  Evaluation of GAFCHROMIC EBT film for Cyberknife dosimetry. , 2007, Medical physics.

[13]  J. Dempsey,et al.  Important considerations for radiochromic film dosimetry with flatbed CCD scanners and EBT GAFCHROMIC® film. , 2006, Medical physics.

[14]  I. Vitkin,et al.  Intra-irradiation changes in the signal of polymer-based dosimeter (GAFCHROMIC EBT) due to dose rate variations , 2007, Physics in medicine and biology.

[15]  H. Bouchard,et al.  Potential errors in optical density measurements due to scanning side in EBT and EBT2 Gafchromic film dosimetry. , 2010, Medical physics.

[16]  M. Butson,et al.  Energy response of the new EBT2 radiochromic film to x-ray radiation , 2010 .

[17]  C. De Wagter,et al.  Precautions and strategies in using a commercial flatbed scanner for radiochromic film dosimetry , 2007, Physics in medicine and biology.

[18]  Suresh Senan,et al.  Whole-brain radiotherapy with simultaneous integrated boost to multiple brain metastases using volumetric modulated arc therapy. , 2009, International journal of radiation oncology, biology, physics.

[19]  Volker Steil,et al.  Optimization of the gafchromic EBT protocol for IMRT QA. , 2009, Zeitschrift fur medizinische Physik.

[20]  Oliver Jäkel,et al.  Analysis of uncertainties in Gafchromic® EBT film dosimetry of photon beams , 2008, Physics in medicine and biology.

[21]  P. Cavazzani,et al.  Fractionated stereotactic radiotherapy: a method to evaluate geometric and dosimetric uncertainties using radiochromic films. , 2009, Medical physics.

[22]  M. Butson,et al.  Evaluation of the magnitude of EBT Gafchromic film polarization effects , 2009, Australasian Physics & Engineering Sciences in Medicine.

[23]  M. Butson,et al.  Absorption spectra variations of EBT radiochromic film from radiation exposure. , 2005, Physics in medicine and biology.

[24]  Dietmar Georg,et al.  Dosimetric characterization of GafChromic EBT film and its implication on film dosimetry quality assurance , 2007, Physics in medicine and biology.

[25]  Martin J Butson,et al.  Measurement of high energy x-ray beam penumbra with Gafchromic™ EBT radiochromic film. , 2006, Medical physics.

[26]  T Kairn,et al.  Modeling a complex micro-multileaf collimator using the standard BEAMnrc distribution. , 2010, Medical physics.

[27]  T Kairn,et al.  Local heterogeneities in early batches of EBT2 film: a suggested solution , 2010, Physics in medicine and biology.

[28]  J. Lárraga-Gutiérrez,et al.  Radiation transmission, leakage and beam penumbra measurements of a micro‐multileaf collimator using GafChromic EBT film , 2008, Journal of applied clinical medical physics.

[29]  Measuring energy response for RTQA Radiochromic film to improve quality assurance procedures , 2008, Australasian Physics & Engineering Sciences in Medicine.

[30]  Elisa Calamia,et al.  Clinical use of EBT model Gafchromic film in radiotherapy. , 2006, Medical physics.

[31]  M. Gillin,et al.  Energy dependence and dose response of Gafchromic EBT2 film over a wide range of photon, electron, and proton beam energies. , 2010, Medical physics.

[32]  D. Rogers,et al.  Monte Carlo calculated absorbed-dose energy dependence of EBT and EBT2 film. , 2010, Medical physics.