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external beam radiation therapy

(... RAY-dee-AY-shun THAYR-uh-pee)
A type of radiation therapy that uses a machine outside the body to send high-energy radiation beams toward the area of the body with cancer. It is used to treat many types of cancer. It may also be used to shrink tumors to treat pain and other problems caused by the tumor, such as trouble breathing or loss of bowel and bladder control. Also called external radiation therapy.
More Information
External-beam radiation therapy of the brain; drawing shows a patient lying on a table under a machine that is used to aim high-energy radiation. An inset shows a mesh mask that helps keep the patient's head from moving during treatment. The mask has pieces of white tape with small ink marks on it. The ink marks are used to line up the radiation machine in the same position before each treatment.Enlarge this image in new window
External-beam radiation therapy of the brain. A machine is used to aim high-energy radiation. The machine can rotate around the patient, delivering radiation from many different angles. A mesh mask helps keep the patient’s head from moving during treatment. Small ink marks are put on the mask. The ink marks are used to line up the radiation machine in the same position before each treatment.
External-beam radiation therapy of the head and neck; drawing shows a patient lying on a table under a machine that is used to aim high-energy radiation at the cancer. An inset shows a mesh mask that helps keep the patient's head and neck from moving during treatment. The mask has pieces of white tape with small ink marks on it. The ink marks are used to line up the radiation machine in the same position before each treatment.Enlarge this image in new window
External-beam radiation therapy of the head and neck. A machine is used to aim high-energy radiation at the cancer. The machine can rotate around the patient, delivering radiation from many different angles to provide highly conformal treatment. A mesh mask helps keep the patient’s head and neck from moving during treatment. Small ink marks are put on the mask. The ink marks are used to line up the radiation machine in the same position before each treatment.
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