Assessment of using Monte Carlo methods in studies related to neutron contamination of radiotherapy in linear accelerator: A comparative review

that are widely used in radiotherapy facilities. Unfortunately, at the time of using radiotherapy with energies higher than 7-8 MeV, high-energy photons interact with components of the accelerator that is used for shaping and modulating the intensity of radiation in the beam path creates neutrons contaminants. In these circumstances, it is crucial to estimate received dose to the patients, doctors and personnel accurately. So the aim of this study is the assessment of using Monte Carlo methods in studies related to neutron contamination of radiotherapy in linear accelerator. Due to the high effectiveness of neutrons compared to the photons and electrons, this unwanted dose can increase the risk of secondary cancers. On the other hand, due to higher flux rate of photon compared to neutrons, limitation and difficulty experimental neutron dosimetry, it is very complex, but the Monte Carlo simulations code have been able to measure dose of each radiation separately, so the simulation is the most prominent method for computing photoneutron contamination. According to the results of the studies conducted by previous researchers from 1990 to 2014, it can be expressed generally that the use of simulation in studies of medical linear accelerators is low-costs, fast and unrestricted. Also, studies show that the results of the simulation have a good agreement with results of practical dosimetry in all of studies that used both methods

Keywords:

Linear accelerator , Neutron contamination , Monte Carlo , Radiotherapy