Automatic-aperture-control accelerator system collimator
Definition
A motorized, radiation beam-limiting device that is a component of a therapeutic accelerator system and composed of highly-attenuating materials or alloys [e.g., lead (Pb), tungsten (W)] with jaw or leaf positioning functions that are computer-controlled. Mounted at the beam exit port, it is used to adjust the shape of the radiation beam to the body area targeted for treatment. It provides patient protection by limiting or eliminating radiation delivery to non-target body areas during treatment. A light localizer is typically included in the design of the device to indicate the location of the radiation beam and assist in the positioning of patients for treatment.