This page about radiation oncology simulations has appeared in UZ Magazine (Sept 2015) of UZ Leuven Hospital in Belgium.
Simulation – More than half of all cancer patients receive radiotherapy treatment at some point. A patient undergoing radiotherapy will come to the simulator a week before the first session to prepare his or her treatment. During the simulation, radiation oncologists, nursing staff and medical imagers determine the position and the exact dose and place of the radiation. For this purpose, they draw reference lines on the patient.
Patients with head/neck-cancer receive a personalized mask that is made to fit, with lines drawn onto it. These lines will guarantee that a patient is placed in the exact same position every time. A scan will make images of the tumour, the glands and other surrounding organs during the preparatory phase. A medical physicist will be able to appoint the areas that need radiation on these images. Based on that information, the radiation physicist determines the ideal radiation schedule: the tumour receives the prescribed radiation dose, the surrounding organs the lowest possible dose.