Small photon field dosimetry using EBT2 Gafchromic film and Monte Carlo simulation

Abstract

Small photon ields are increasingly used in modern radiotherapy especially in intensity modulated radiation therapy (IMRT) and stereotactic radiosurgery (SRS) treatments. It is dif icult to measure beam pro iles, central axis depth doses and output factors in small ields accurately. That is related to the electron disequilibrium (1), partial blocking of the beam source (2, 3), steep dose gradients and perturbation due to different density of the detector and the medium (4, 5). Due to these M. Yarahmadi1,2, H.A. Nedaie2,3*, M. Allahverdi2, Kh. Asnaashari3, O.A. Sauer4