MAIN FEATURES FOR A NEW RADIOTHERAPY DEVICE BASED ON A SINGLE CONVERGENT BEAM OF PHOTONS (RTHC)
Resumen
A new radiotherapy technique based on a single convergent photons beam (RTHC: Radioterapia de Haz Convergente) by means of a device capable to generate a single beam of convergent X photons has been proposed. Previous studies have shown that a primary beam of these characteristics provides excellent dosimetric results with a dose peak close to the isocenter, similar those used for hadron therapy treatment. To determine the physical and dosimetric characteristics of a device convergent X photons beam and its potential to be used in clinical treatments. Analytical developments plus software that allows determining the necessary fields (electrostatic and/or magnetic fields) for electrons trajectory control are used. Monte Carlo simulation code (PENELOPE) is applied to a specially designed geometry for the generation of a convergent photons beam. We determined the values of the magnetic and/or electric fields to handle the convergent beam device for an electrons’ energy range from 0.1 to 20 MeV. Angular distribution curves of the bremsstrahlung were determined for different thicknesses and incident electrons energies (0.4 to 6.0 MeV), plus the respective doses distribution in each case, characterized by a high dose concentration, close to the isocenter. We can conclude that the physical and dosimetric characteristics of convergent beam device radiotherapy have been determined. The achieved results show that it is possible to develop a convergent beam prototype of low and high energy as a single unit or to be adapted to an existing radiation-therapy LINAC, so this might be used either in the conventional mode or in the conventional one, depending on the case.
Autor de correspondencia: Rodolfo Figueroa S. (rodolfo.figueroa @ ufrontera.cl)
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