CT simulation is a process used by the radiation therapy team to determine the exact location, shape, and size of the tumor to be treated. This is done in a separate room that contains a treatment table and special imaging equipment.
During simulation, you will lie on the treatment table. The radiation therapist will position you in the precise way you will ultimately be treated and then watch you through a window while a CT scanner takes images of the treatment site. You must lie still during simulation so the exact area to be treated can be pinpointed.
The radiation therapist may use special pads, body molds or other devices to help hold your body comfortably in the proper position.
After your radiation oncologist locates the exact area to be treated, your skin may be marked with several small tattoos, each the size of a freckle. These tiny, permanent dots will be used to make sure you are accurately positioned at each treatment session.