Iranian Journal of Medical Physics

Iranian Journal of Medical Physics

Quality Assurance of LINAC by Analyzing the Profile of 6-MV and 10-MV Photon Beams Using Star Track Device

Document Type : Original Paper

Authors
Basma Sabur Lazim 1
Basim Khalaf Rejah 2
Haydar H. Alabedi 3
1 Physics Department, College of Science for Women
2 University of Baghdad / College of Science for Women / Department of Physics
3 Ministry of Health and Environment, Baghdad Center for Radiation Therapy and Nuclear Medicine
10.22038/ijmp.2019.39987.1543
Abstract
Introduction: According to the American Society of Radiation Oncology, all patients receive radiation therapy during their illness, where radiation is delivered by the medical linear accelerator (Linac). The aim of this study was to evaluate the quality assurance (QA) of the Linac in analyzing the used dose profile in the treatment of cancer tumors.
Material and Methods: This experimental study was performed using Linac (synergy device type) at Baghdad Radiotherapy and Nuclear Medicine laboratories, Baghdad, Iraq. The Star Track device was used for the routine quality assurance of the Linac, using photon beam for the reference Dmax and source to surface distance of 100 cm. The Star Track consists of 453 vented parallel plate ionization chambers.
Results: The flatness and symmetry of beams for the reference field size did not exceed from ±2%, as they were within the allowed range. Moreover, the penumbra region showed a change in value that did not exceed from ±0.2 cm. using the Star Track method; maximum differences in beam symmetry and beam flatness were measured at 0.76%±2% and 1.17%±2%, respectively. Moreover, the maximum difference in the penumbra region was estimated at 0.12±0.2 cm.
Conclusion: The results indicated, the Star Track could successfully calculate the characteristics of dose profile during a time period of 2,500 ms, showing the superiority of this instrument over other verification devices.
Keywords
Linear Accelerator
Star Track
Radiation Therapy
Iraq
Subjects

  1. References

     

    1. Shrotriya D, Yadav S, Lal Srivastava N. Surface Dose Measurements on an Indigenously Made Inhomogeneous Female Pelvic Phantom. Using Metal-Oxide-Semiconductor-Field-Effect-Transistor Based Dosimetric System. Iran J Med Phys. 2018; 15(4): 304-7.
    2. Krabch M, Chetaine A,  Saidi K, Errad FT, Nourreddine A, Benkhouya Y, et al. Measurements of Photon Beam Flattening Filter Using an Anisotropic Analytical Algorithm and Electron Beam Employing Electron Monte Carlo.Iran J Med  Phys. 2019;16(6):200-9.
    3. Pathak P, Mishra PK, Singh M, Mishra PK. Cancer Science & Therapy Analytical Study of Flatness and Symmetry of Electron Beam with 2D array detectors. journal of cancer science and therapy. 2015;7(10):294–301.
    4. Hanley J, Bayouth J. Task Group 142 report: quality assurance of medical accelerators. Med Phys. 2009; 36 (9):4197–212. 
    5. Farrukh S, Ilyas N, Naveed M, Haseeb A, Bilal M. Penumbral dose characteristics of physical and virtual wedge profiles. international journal of medical physics. 2017; 6: 216–24.
    6. Hegazy EA . Evaluation of using radiographic films in measurements of penumbra width for radiotherapy applications evaluation of using radiographic films in measurements of penumbra width for radiotherapy applications. Journal of advancesin physics. 2018;14(1):5204-12.      
    7. Das J, Cheng W, Watts R, Ahnes  J, Gibbons  X, Lowenstein Li, et al. Report of the TG-106 of the Therapy Physics Committee of the AAPM: Accelerator beam data commissioning equipment and procedures. J Medical Physics. 2008; 35: 4186–215. 
    8. Patatoukas GD, Kalavrezos P, Seimenis I, Dilvoi M, Efstathopoulos E, Platoni K. Determination of beam profile characteristics in radiation therapy using different dosimetric set ups. JBUON. 2018; 23(5):1448–59.
    9. Enoch M, Mcdonald K. Dose distribution in 3D water phantom and profiler 2 scanning system. IJSBAR. 2017; 34 (3) : 149-57.   
    10. Speight RJ, Esmail A, Weston SJ. Quality assurance of electron and photon beam energy using the BQ-Check phantom.journal of appled clincal medical physics. 2011;12 (2): 293-44 .
    11. Pereira GC, Traughber M, Muzic RF. The Role of imaging in radiation therapy planning: past, present, and future. Biomed Res Int. 2014 ;2: 1–9.               
    12. Billan S, Charas T , Billan S, Charas T. External beam radiation in differentiated thyroid arcinoma. Rambam Maimonides. Med J. 2016; 7(1): 1-6. 
    13. Yorke E, Gelblum D, Ford E. Patient safety in external beam radiation therapy. Am J Roentgenol. 2011 ; 196 (4) :768–72.
    14. Khan FM. the  Physics of radiation therapy. 4th ed. williams & wilkins. 2010;33-45.
    15. Diamantopoulos S, Thalassinou S. In vivo dosimetry in the field junction area for 3D-conformal radiation therapy in breast and head & neck cancer cases: A quality assurance study. JBUON. 2016; 21:1104-12.
    16. Yarahmadi M, Nedaie HA, Allahverdi M, Asnaashari KH, Sauer OA .Small photon field dosimetry using EBT2 Gafchromic film and Monte Carlo simulation. Int J Radiat Res. 2013; 11(4):215-24.
    17. Khan  FM. the physicie of radation therapy.5thed .wolters klvwer. 2014;413-20.
    18. Ravichandran R, Binukumar JP, Davis CA, Krishnamurthy K, Sivakumar SS. Evaluation methods for detecting changes in beam output and energy in radiation beams from high-energy linear Accelerators. Med Phys. 2007; 32 (3):5-40.
    19. Tajiki S, Nedaie HA, Esfehani M, Geraily Gh, Hassani M, Rastjoo A, et al. Penumbra Measurements and Comparison of In-House and Standard Circular Cones by the Gafchoromic Film Pinpoint Ion Chamber, and MCNPX Monte Carlo Simulation. Iran J Med Phys. 2019; 16(3):232-40.

     

     

Iranian Journal of Medical Physics
Volume 17, Issue 4 - Serial Number 4
July and August 2020
Pages 260-265

  • Receive Date 29 April 2019
  • Revise Date 11 July 2019
  • Accept Date 13 July 2019