Development of a one-stop beam verification system using electronic portal imaging devices for routine quality assurance

Sangwook Lim, Sun Young Ma, Tae Sig Jeung, Byong Yong Yi, Sang Hoon Lee, Suk Lee, Sam Ju Cho, Jinho Choi

Research output: Contribution to journalArticle

3 Citations (Scopus)


In this study, a computer-based system for routine quality assurance (QA) of a linear accelerator (linac) was developed by using the dosimetric properties of an amorphous silicon electronic portal imaging device (EPID). An acrylic template phantom was designed such that it could be placed on the EPID and be aligned with the light field of the collimator. After irradiation, portal images obtained from the EPID were transferred in DICOM format to a computer and analyzed using a program we developed. The symmetry, flatness, field size, and congruence of the light and radiation fields of the photon beams from the linac were verified simultaneously. To validate the QA system, the ion chamber and film (X-Omat V2; Kodak, New York, NY) measurements were compared with the EPID measurements obtained in this study. The EPID measurements agreed with the film measurements. Parameters for beams with energies of 6 MV and 15 MV were obtained daily for 1 month using this system. It was found that our QA tool using EPID could substitute for the film test, which is a time-consuming method for routine QA assessment.

Original languageEnglish
Pages (from-to)296-304
Number of pages9
JournalMedical Dosimetry
Issue number3
Publication statusPublished - 2012 Jan 23



  • Daily QA
  • EPID
  • Radiation field

ASJC Scopus subject areas

  • Oncology
  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology

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