Electron Virtual Wedge: Validation and Dosimetric Evaluation

Virtual wedge (VW) was developed in mid-nineties and has been used in photon radiotherapy since then. The idea was that a dose profile similar to that obtained by physical wedge can be generated by moving one of the collimator jaws at a constant speed while changing the dose rate. In this paper, validation of electron VW was made and the dosimetric properties of 7, 10, 12 and 14 MeV electron beams from a Siemens Mevatron linear accelerator, including percentage depth doses and dose profiles for 10 × 10 cm² and 15 × 15 cm² applicators, were determined. In addition, comparison between depth doses for open and wedged fields for all studied applicators and energies was made. This study showed that the validation of VW on electron radiotherapy is visible and the behavior of VW in electron beams is similar to that of photon beams.