Abstract
EBT3 film is utilized as a dosimetry quality assurance tool for the verification of clinical radiotherapy treatments. In this work, we suggest a percentage-depth-dose (PDD) calibration method that can calibrate several EBT3 film pieces together at different dose levels because photon beams provide different dose levels at different depths along the axis of the beam. We investigated the feasibility of the film PDD calibration method based on PDD data and compared the results those from the traditional film calibration method. Photon beams at 6 MV were delivered to EBT3 film pieces for both calibration methods. For the PDD-based calibration, the film pieces were placed on solid phantoms at the depth of maximum dose (dmax) and at depths of 3, 5, 8, 12, 17, and 22 cm, and a photon beam was delivered twice, at 100 cGy and 400 cGy, to extend the calibration dose range under the same conditions. Fourteen film pieces, to maintain their consistency, were irradiated at doses ranging from approximately 30 to 400 cGy for both film calibrations. The film pieces were located at the center position on the scan bed of an Epson 1680 flatbed scanner in the parallel direction. Intensity-modulated radiation therapy (IMRT) plans were created, and their dose distributions were delivered to the film. The dose distributions for the traditional method and those for the PDD-based calibration method were evaluated using a Gamma analysis. The PDD dose values using a CC13 ion chamber and those obtained by using a FC65-G Farmer chamber and measured at the depth of interest produced very similar results. With the objective test criterion of a 1% dosage agreement at 1 mm, the passing rates for the four cases of the three IMRT plans were essentially identical. The traditional and the PDD-based calibrations provided similar plan verification results. We also describe another alternative for calibrating EBT3 films, i.e., a PDD-based calibration method that provides an easy and time-saving approach to film calibration.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
S. Devic, Phys. Med. 27, 122 (2011).
M. A. Carrasco, M. Perucha, F. J. Luis, M. Baeza and M. Herrador, Phys. Med. 29, 412 (2013).
M. Todorovic, M. Fischer, F. Cremers, E. Thom and R. Schmidt, Med. Phys. 33, 1321 (2006).
B. Arjomandy, R. Tailor, A. Anand, N. Sahoo, M. Gillin, K. Prado and M. Vicic, Med. Phys. 37, 1942 (2010).
S. Devic, S. Aldelaijan, H. Mohammed, N. Tomic, L. H. Liang, F. DeBlois and J. Seuntjens, Med. Phys. 37, 2207 (2010).
J. Desroches, H. Bouchard and F. Lacroix, Med. Phys. 37, 1565 (2010).
S. Park et al., Med. Phys. 39, 2524 (2012).
B. Hartmann, M. Martisikova and O. Jakel, Med. Phys. 37, 1753 (2010).
A. Niroomand-Rad et al., Med. Phys. 25, 2093 (1998).
S. Pai et al., Med. Phys. 34, 2228 (2007).
B. C. Ferreira, M. C. Lopes and M. Capela, Phys. Med. Biol. 54, 1073 (2009).
C. Fiandra, U. Ricardi, R. Ragona, S. Anglesio, F. R. Giglioli, E. Calamia and F. Lucio, Med. Phys. 33, 4314 (2006).
L. Richley, A. C. John, H. Coomber and S. Fletcher, Phys. Med. Biol. 55, 2601 (2010).
L. Chang, C. S. Chui, H. J. Ding, I. M. Hwang and S. Y. Ho, Phys. Med. Biol. 57, 5875 (2012).
L. Chang, S. Y. Ho, T. F. Lee, S. A. Yeh, H. J. Ding and P. Y. Chen, Med. Phys. 42, 5838 (2015).
IAEA Technical Reports Series No. 398 (International Atomic Energy Agency, Vienna, 2004).
C. Andres, A. del Castillo, R. Tortosa, D. Alonso and R. Barquero, Med. Phys. 37, 6271 (2010).
L. Paelinck, W. De Neve and C. De Wagter, Phys. Med. Biol. 52, 231 (2007).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Park, S., Kang, SK., Cheong, KH. et al. Alternate calibration method of radiochromic EBT3 film for quality assurance verification of clinical radiotherapy treatments. Journal of the Korean Physical Society 69, 248–252 (2016). https://doi.org/10.3938/jkps.69.248
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.3938/jkps.69.248