A linear accelerator (LINAC) customizes high energy x-rays to conform to a tumorís shape and destroy cancer cells while sparing surrounding normal tissue. It features several built-in safety measures to ensure that it will not deliver a higher dose than prescribed and is routinely checked by the medical physicist to ensure it is working properly.
If youíre scheduled for radiation therapy using a LINAC, your radiation oncologist will collaborate with a radiation dosimeters and a medical physicist to develop a treatment plan for you. Your doctor will double-check this plan before treatment begins and implement quality control procedures to ensure that each treatment is delivered in the exact same manner.
What is this equipment used for?
A linear accelerator (LINAC) is the device most commonly used for external beam radiation treatments for patients with cancer. The linear accelerator is used to treat all parts/organs of the body. It delivers high-energy x-rays to the region of the patient's tumor. These x-ray treatments can be designed in such a way that they destroy the cancer cells while sparing the surrounding normal tissue. The LINAC is used to treat all body sites, using conventional techniques,
How does the equipment work?
The linear accelerator uses microwave technology (similar to that used for radar) to accelerate electrons in a part of the accelerator called the "wave guide," then allows these electrons to collide with a heavy metal target to produce high-energy x-rays. These high energy x-rays are shaped as they exit the machine to conform to the shape of the patient's tumor and the customized beam is directed to the patient's tumor. The beam may be shaped either by blocks that are placed in the head of the machine or by a multileaf collimator that is incorporated into the head of the machine. The patient lies on a moveable treatment couch and lasers are used to make sure the patient is in the proper position. The treatment couch can move in many directions including up, down, right, left, in and out. The beam comes out of a part of the accelerator called a gantry, which can be rotated around the patient. Radiation can be delivered to the tumor from any angle by rotating the gantry and moving the treatment couch.
Who operates this equipment?
The patient's radiation oncologist prescribes the appropriate treatment volume and dosage. The medical radiation physicist and the dosimeters determine how to deliver the prescribed dose and calculate the amount of time it will take the accelerator to deliver that dose. Radiation therapists operate the linear accelerator and give patients their daily radiation treatments.