Application of Virtual Wedge in Electron Beams of Mevatron Linear Accelerator

In the year, 1997 Siemens introduced the virtual wedge (VW) in its linear accelerators for the use in photon beams radiation treatment. The idea was that a dose profile similar to that of a physical wedge can be obtained by moving one of the accelerator jaws at a constant speed and changing the dose rate. The application of VW is restricted for the photon beams Therefore, in this paper we developed the use of VW in electron beams of energies 7, 10, 12 and 14 MeV generated from a Siemens Mevatron linear accelerator. Dosimetric parameters including percentage depth doses (PDDs) and dose profiles for 10 × 10 cm2 and 15 × 15 cm2 applicators were measured. In addition, comparison between depth doses for open and wedged fields for all applicators and energies was made. This study showed that using the principles of VW in electron beams is visible and no difference in PDDs of VW beams compared with open beams.