Iranian Journal of Medical Physics

Iranian Journal of Medical Physics

Use of Amorphous Silicon (ASi) Electronic Portal Imaging Devices for Other applications for Linear Accelerator Quality Assurance

Document Type : Original Paper

Authors
Gena Mohamed 1
Khaled M. El-Shahat 2
Mahmoud Salem 3
Atef El-Taher 4
1 Assiut Military Center for Radiotherapy, Assiut, Egypt
2 Faculty of Medicine, Al Azhar University, Egypt
3 Physics Department, Faculty of Science, New Valley University, 72511, El-Kharga, Egypt.
4 Physics Department, Faculty of Science, Al Azhar University, Assuit
10.22038/ijmp.2020.45434.1701
Abstract
Introduction: The success of radiation therapy depends critically on the accuracy of patient alignment in treatment position day after day. The primary use for Electronic portal imaging devices (EPIDs) is to monitor patient position during daily radiotherapy sessions. Recently the role of EPIDs has been expanded beyond patient imaging to become a useful tool for radiotherapy dosimetry.
Material and Methods: To test another application of linac quality assurance (QA), 10×10 cm2 and 18×18 cm2 images of an open field were obtained. The epidermis was located at a fixed detector distance of 150 cm. Results: Wedge profile and wedge factors with a high level of accuracy demonstrated. The profiles acquired using EPID deviated in shape and magnitude by up to 16% from the ion chamber profiles. The use of EPID for linac QA can be simplified by improving the available software analysis tools, which will increase its efficiency. According to the findings, the EPID aSi500 has the potential to be used as a relative dosimeter, making it a straightforward and efficient tool for daily QA.
Conclusion: All EPID measurements were performed using the linear accelerator Varian DMX. Based on the physical characteristics, as an efficient tool, the SLIC-EPID can be used for daily QA.
Keywords
Portal Imaging
Dosimetric Properties
Electronic Portal Imaging Devices (EPID)
Radiation Dosimetry
Subjects

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Iranian Journal of Medical Physics
Volume 18, Issue 4
July and August 2021
Pages 285-292

  • Receive Date 29 December 2019
  • Revise Date 08 May 2020
  • Accept Date 14 May 2020