Abstract
We constructed seven intensity-modulated radiation therapy (IMRT) treatment plans for prostate cancer (49 irradiation fields which contained seven randomly-sampled patients and seven fields) and evaluated the dose distributions by using a radiochromic film (EBT3 film) and a 2D detector. We superposed the calculated dose distribution of the IMRT treatment plan on EBT3 film and the 2D detector results and then compared those with the γ-analysis pass rate. The relative positions of the beam and the detector were varied; the results of the analysis of the superior-inferior (SI) direction potentially differed, depending on the detector position, under an irradiation beam with the same fluence map. The detector was moved over a range of’ 8 mm in the SI direction in 1-mm step increments, measurement were made at each position, and the results were analyzed. The γ-analysis compared the dose distributions from EBT3 film and the radiation treatment planning system (RTPS) for each patient and field; the pass rate with the γ-analysis from 98 to 100% was 2.04%. When we compared the dose distributions of the 2D detector and the RTPS, the pass rate from 98 to 100% was 63.2%. The mean values for the ?-analysis pass rates for EBT3 film and the 2D detector were 94.2 and 97.6%, respectively. Volume averaging of the data indicated a mean pass rate and standard deviation of 98.6 and 0.91%, respectively, and a pass rate of more than 96% for all positions. A 2D detector can, therefore, be used as an alternative apparatus for IMRT dose verification.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
M. Miyazawa, Jpn. J. Rad. Tech. 62, 1428 (2006).
M. J. Butsun, T. Cheung and P. K. N. Yu, Australa’s Phys. Eng. Sci. Med. 29, 281 (2006).
L. J. van Battum, D. Hoffmans and H. Piersma, Med. Phys. 35, 704 (2008).
L. D. Wolfsberger, M. Wagar and P. Nisch, J. Appl. Clin. Med. Phys. 11, 241 (2010).
R. Boggula, M. Birkner and F. Lohr, Phys. Med. Biol. 56, 7163 (2011).
Y. Shimohigashi, F. Araki, H. Tominaga, J. Sakata and K. Kawasaki, J. Appl. Clin. Med. Phys. 13, 198 (2012).
P. A. Jursinic and B. E. Nelms, Med. Phys. 30, 870 (2003).
F. B. Buonamici et al., Med. Phys. 34, 1372 (2007).
J. G. Li, G. Yan and C. Liu, J. Appl. Clin. Med. Phys. 10, 62 (2009).
J. M. Bland and D. G. Altman, The Lancet 327, 307 (1986).
O. A. Zeidan, S. A. Stephenson and S. L. Meeks, Med. Phys. 33, 4064 (2006).
H. Tominaga, S. Tajiri and K. Kawasaki, Jpn. J. Rad. Tech. 62, 1193 (2006).
N. V. Klassen, L. V. Zwan and J. Cygler, Med. Phys. 24, 1924 (1997).
Y. Nakaguchi, F. Araki, S. Saiga, T. Kouno, M. Maruyama, K. Kakei, N. Nagasue and M. Hashida, Jpn. J. Rad. Tech. 4, 443 (2012).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Onishi, Y., Nakayama, S., Watanabe, S. et al. Comparison of dose accuracy between film and two-dimensional detectors in intensity-modulated radiation therapy. Journal of the Korean Physical Society 67, 89–95 (2015). https://doi.org/10.3938/jkps.67.89
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.3938/jkps.67.89