Use of Electron Beam under Effect of Magnetic Field to Optimize the Pattern of Prescribed Dose in Patients under Radiation Therapy

Document Type : Original Article

Authors

1 Department of Medical Physics, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.

2 Department of Medical Physics, School of Allied Medical Sciences, Arak University of Medical Sciences, Arak, Iran.

3 Department of Radiotherapy and Oncology, Golestan Hospital, Ahvaz Jundishapur University of Medical sciences, Ahvaz, Iran.

Abstract

Background and Objective:In radiation therapy,depending on the depth and type of the tumor, photon or electron irradiation is often applied to treat malignant tumors. Normal tissues are inevitably damaged, due to dose absorption. Since the electron beam is deviated by the magnetic field, it could be applied to detour the dose deposition from normal tissues to tumor mass. 
Subjects and Methods: 15MeV electron beam, produced with Varian clinac 2100C/D, was used in this research. Relative dosimetry process was done by use of 3D water phantom and CC13 cylindrical chamber. This process was accomplished with and without magnetic field. 
Results: After use of magnetic field the surface dose was  increased. In addition the dose in buildup region had incremented.the depth of maximum dose in presence of magnetic field had a shift rather than without magnetic field. The penumbra had increment in some directions and decrease in some other directions.
Conclusion: By applying the magnetic field one can produce a region with increased and adjacent to a lower dose. It seems that arrangement of this region over normal and tumoral region can lead to increase in the efficiency of radiation therapy.

Keywords

References

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Jundishapur Scientific Medical Journal
Volume 13, Issue 1 - Serial Number 88
March and April 2014
Pages 78-88

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History

  • Receive Date: 16 September 2012
  • Revise Date: 30 January 2013
  • Accept Date: 14 December 2017

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