Monte Carlo simulation is a computerized mathematical technique that models the estimates of various outcomes in a problem that cannot be predicted due to the interference of random variables Monte Carlo method is used so that the risk and the uncertainty in prediction can be understood (Kenton, 2019). Since 1970, the Monte Carlo method is used to solve problems in the field of radiotherapy dosimetry with its applications ranging from the calculation of dosimetric quantities to simulating radiotherapy treatment planning (Andreo, 2018).
In early applications, the limited computer power was a major factor concerning the geometries which were simulated.
Only basic, like cylinders and parallel slabs, could be produced limiting the applications but with today’s technological advancements and the available computer power, complicated, detailed and three-dimensional geometries like those used for linear accelerator treatment heads, detectors and patient treatments using CT data can be easily simulated allowing easier and safer treatment planning (Andreo, 2018).
In every situation the characteristics of the energy, position and direction of the particles that reach a detector or a patient’s organ can be determined allowing the calculation of dosimetric quantities such as absorbed dose and fluence (Andreo, 2018).