Journal of Radiation Safety and Measurement

Journal of Radiation Safety and Measurement

Measuring the leakage dose of TiGRT Dynamic MLC with EDGE diode dosimeter and EBT3 radiochromic film and comparing the results with BEAMnrc code calculations

Document Type : Conference Paper

Authors
Mikaeil Molazadeh 1
Ahad Zeinali 1
Mostafa Robatjazi 2
Ghazale Geraily 3
1 Department of Medical Physics, Faculty of Medicine, Urmia University of Medical Sciences, Urmia, Iran
2 Department of Medical Physics and Radiological Sciences, Sabzevar University of Medical Sciences, Sabzevar, Iran
3 Department of Medical Physics and Biomedical Engineering, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran
Abstract
One of the key factors in the assessment of the quality assurance in advanced radiotherapy treatments such as IMRT and VMAT is obtaining different types of dose leakages related to the MLCs used in these techniques. In this study, different dose leakage parameters from TiGRT Dynamic MLC, which was externally added to the lower part of the collimator system of Siemens linear accelerator, were measured using different dosimeters (diode dosimeter and radiochromic film) and compared with Monte Carlo simulation results. Measurement indices include radiation beam leakage from the air gap between the leaves (inter-leaf leakage), the amount of X-ray passage through individual leaves (intra-leaf transmission), average leakage and leakage related to the air gap of the leaves in the completely closed radiation field (abutting air gap leakage) were at  6-MV energy. In measuring the various leakage dose indices from TiGRT Dynamic MLC, a good agreement was observed between the measured data and the simulation results. According to the TG-50 protocol, the average interleaf leakage and interleaf leakage should be less than 2%; and the results of our study showed that the leakage parameters obtained from this type of MLC agree with the universal protocols.
Keywords
MLC leakage
EGSnrc code
EBT3 film
EDGE diode dosimeter
MLC quality assurance
  1. K. Otto. Volumetric modulated arc therapy: IMRT in a single gantry arc. Med. Phys. 35 (1) (2008) 310-317.
  2. T. Y. Lim, I. Dragojević, D. Hoffman, E. Flores-Martinez, G. Y. Kim. Characterization of the HalcyonTM multileaf collimator system. J. Appl. Clin. Med. Phys. 20 (4) (2019) 106-114.
  3. S. Rohani, S. Mahdavi, A. Mostaar, S. Ueltzhöffer, R. Mohammadi, G. Geraily. Physical and dosimetric aspect of euromechanics add-on multileaf collimator on varian clinac 2100 C/D. J. Bio. Phys. Eng. 9 (1) (2019) 29-36.
  4. S. Agostinelli, J. Allison, K. Amako, J. Apostolakis, H. Araujo, P. Arce, M. Asai, D. Axen, S. Banerjee, G. Barrand, F. Behner, L. Bellagamba, J. Boudreau, L. Broglia, A. Brunengo, H. Burkhardt, S. Chauvie, J. Chuma, R. Chytracek, G. Cooperman, G. Cosmo, P. Degtyarenko, A. Dell'Acqua, G. Depaola, D. Dietrich, R. Enami, A. Feliciello, C. Ferguson, H. Fesefeldt, G. Folger, F. Foppiano, A. Forti, S. Garelli, S. Giani, R. Giannitrapani, D. Gibin, J.J. Gómez Cadenas, I. González, G. Gracia Abril, G. Greeniaus, W. Greiner, V. Grichine, A. Grossheim, S. Guatelli, P. Gumplinger, R. Hamatsu, K. Hashimoto, H. Hasui, A. Heikkinen, A. Howard, V. Ivanchenko, A. Johnson, F.W. Jones, J. Kallenbach, N. Kanaya, M. Kawabata, Y. Kawabata, M. Kawaguti, S. Kelner, P. Kent, A. Kimura, T. Kodama, R. Kokoulin, M. Kossov, H. Kurashige, E. Lamanna, T. Lampén, V. Lara, V. Lefebure, F. Lei, M. Liendl, W. Lockman, F. Longo, S. Magni, M. Maire, E. Medernach, K. Minamimoto, P. Mora de Freitas, Y. Morita, K. Murakami, M. Nagamatu, R. Nartallo, P. Nieminen, T. Nishimura, K. Ohtsubo, M. Okamura, S. O'Neale, Y. Oohata, K. Paech, J. Perl, A. Pfeiffer, M.G. Pia, F. Ranjard, A. Rybin, S. Sadilov, E. Di Salvo, G. Santin, T. Sasaki, N. Savvas, Y. Sawada, S. Scherer, S. Sei, V. Sirotenko, D. Smith, N. Starkov, H. Stoecker, J. Sulkimo, M. Takahata, S. Tanaka, E. Tcherniaev, E. Safai Tehrani, M. Tropeano, P. Truscott, H. Uno, L. Urban, P. Urban, M. Verderi, A. Walkden, W. Wander, H. Weber, J.P. Wellisch, T. Wenaus, D.C. Williams, D. Wright, T. Yamada, H. Yoshida, D. Zschiesche, GEANT4—a simulation toolkit. Nucl. Instrum. Methods Phys. Res. Sec. A: Accelerators, Spectrometers, Detectors and Associated Equipment 506 (3) (2003) 250-303.
  5. I. Kawrakow, E. Mainegra-Hing, D. W. O. Rogers, F. Tessier, B. R. B. Walters. The EGSnrc Code System: Monte Carlo Simulation of Electron and Photon Transport. Report PIRS-701, Techreport PIRS-701, National Research Council Canada (2001–2015 [version 2018]).
  6. M. Molazadeh, M. Robatjazi, G. Geraily, H. Rezaeejam, A. Zeinali, A. Shirazi. Three-dimensional IMRT QA of Monte Carlo and full scatter convolution algorithms based on 3D film dosimetry. Radiat. Phys. Chem. 186 (2021) 109528.
  7. C. F. D. Zamo, M. N. Moyo. Validation of a 3D Pretreatment Quality Assurance Tool for Volumetric Modulated Arc Therapy (VMAT). Open Access Lib. J. 8 (6) (2021) 1-16.
  8. A. Boyer, P. Biggs, J. Galvin, E. Klein, T. LoSasso, D. Low, K. Mah, C. Yu. Basic Applications of Multileaf Collimators. American Association of Physicists in Medicine, Alexandria, VA, 2001.
  9. S. Devic, J. Seuntjens, E. Sham, E. B. Podgorsak, C. R. Schmidtlein, A. S. Kirov, C. G Soares. Precise radiochromic film dosimetry using a flat‐bed document scanner. Med. Phys. 32 (7Part1) (2005) 2245-2253.
  10. A. Niroomand-Rad, C. R. Blackwell, B. M. Coursey, K. P. Gall, J. M. Galvin, W. L. McLaughlin, A. S. Meigooni, R. Nath, J. E. Rodgers, C. G. Soares. Radiochromic film dosimetry: recommendations of AAPM radiation therapy committee task group 55. Med. Phys. 25 (11) (1998) 2093-2115.
  11. International Atomic Energy Agency. Absorbed dose determination in external beam radiotherapy: an international code of practice for dosimetry based on standards of absorbed dose to water. IAEA TRS-398. Vienna: IAEA; 2001.
  12. G. A. Ezzell, J. W. Burmeister, N. Dogan, T. J. LoSasso, J. G. Mechalakos, D. Mihailidis, A. Molineu, J. R. Palta, C. R. Ramsey, B. J. Salter, J. Shi, P. Xia, N. J. Yue, Y. Xiao. IMRT commissioning: multiple institution planning and dosimetry comparisons, a report from AAPM Task Group 119. Med. Phys. 36 (11) (2009) 5359-5373.
  13. R. Topolnjak, U. Van Der Heide, G. Meijer, B. Van Asselen, C. Raaijmakers, J. Lagendijk. Influence of the linac design on intensity-modulated radiotherapy of head-and-neck plans. Phys. Med. Bio. 52 (1) (2006) 169.
  14. Q. J. Wu, Z. Wang, J. P. Kirkpatrick, Z. Chang, J. J. Meyer, M. Lu, C. Huntzinger, F.-F. Yin. Impact of collimator leaf width and treatment technique on stereotactic radiosurgery and radiotherapy plans for intra-and extracranial lesions. Radiat. Oncology 4 (1) (2009) 1-10.