Electron Beam Dose Distribution in the Presence of Non-Uniform Magnetic Field

Tahmasebi-Birgani, Mohamad Javad; Bayatiani, Mohamad Reza; Seif, Fatemeh; Zabihzadeh, Mansur; Shahbazian, Hojatolah

doi:10.22038/ijmp.2014.2630

Electron Beam Dose Distribution in the Presence of Non-Uniform Magnetic Field

Document Type : Original Paper

Authors

Mohamad Javad Tahmasebi-Birgani ¹

Mohamad Reza Bayatiani ²

Fatemeh Seif ²

Mansur Zabihzadeh ¹

Hojatolah Shahbazian ¹

¹ Department of Medical Physics, JundishapurUniversity of Medical Sciences, Ahvaz, Iran

² Radiotherapy and Medical Physics Department of Arak University of Medical Sciences&Khansari Hospital, Arak, Iran

10.22038/ijmp.2014.2630

Abstract

Introduction
Magnetic fields are capable of altering the trajectory of electron beams andcan be used in radiation therapy.Theaim of this study was to produce regions with dose enhancement and reduction in the medium.
Materials and Methods
The NdFeB permanent magnets were arranged on the electron applicator in several configurations. Then, after the passage of the electron beams (9 and 15 MeV Varian 2100C/D) through the non-uniform magnetic field, the Percentage Depth Dose(PDDs) on central axis and dose profiles in three depths for each energy were measured in a 3D water phantom.
Results
For all magnet arrangements and for two different energies, the surface dose increment and shift in depth of maximum dose (dmax) were observed. In addition, the pattern of dose distribution in buildup region was changed. Measurement of dose profile showed dose localization and spreading in some other regions.
Conclusion
The results of this study confirms that using magnetic field can alter the dose deposition patterns and as a result can produce dose enhancement as well as dose reduction in the medium using high-energy electron beams. These effects provide dose distribution with arbitrary shapes for use in radiation therapy.

Keywords

Electron Beam

Magnetic Field

Radiation Therapy

Subjects