MAIN FEATURES FOR A NEW RADIOTHERAPY DEVICE BASED ON A SINGLE CONVERGENT BEAM OF PHOTONS (RTHC)

R. FIGUEROA; P. BELMAR, R. ELIAS, M. FUENZALIDA & M. VALENTE; J. VELASQUEZ; J. COFRE; R. FUENTES; M.VALENTE

San Jose

Congreso; ALFIM 2013; 2013

ALFIM

A new radiotherapy technique based on a singleconvergent photons beam (RTHC: Radioterapia de HazConvergente) by means of a device capable togenerate a single beam of convergent X photons hasbeen proposed. Previous studies have shown that aprimary beam of these characteristics providesexcellent dosimetric results with a dose peak close tothe isocenter, similar those used for hadron therapytreatment. To determine the physical and dosimetriccharacteristics of a device convergent X photons beamand its potential to be used in clinical treatments.Analytical developments plus software that allowsdetermining the necessary fields (electrostatic and/ormagnetic fields) for electrons trajectory control areused. Monte Carlo simulation code (PENELOPE) isapplied to a specially designed geometry for thegeneration of a convergent photons beam. Wedetermined the values of the magnetic and/or electricfields to handle the convergent beam device for anelectrons? energy range from 0.1 to 20 MeV. Angulardistribution curves of the bremsstrahlung weredetermined for different thicknesses and incidentelectrons energies (0.4 to 6.0 MeV), plus the respectivedoses distribution in each case, characterized by a highdose concentration, close to the isocenter. We canconclude that the physical and dosimetriccharacteristics of convergent beam device radiotherapyhave been determined. The achieved results show thatit is possible to develop a convergent beam prototype oflow and high energy as a single unit or to be adapted toan existing radiation-therapy LINAC, so this might beused either in the conventional mode or in theconventional one, depending on the case.