Also, external radiation therapy commonly causes hair loss from the part of the head that was treated. Hair usually grows back within a few months. Radiation therapy also may make the skin on the scalp and ears red, dry, and tender. The health care team can suggest ways to relieve these problems. Sometimes radiation therapy causes brain tissue to swell. You may get a headache or feel pressure. The health care team watches for signs of this problem. They can provide medicine to reduce the discomfort. Radiation sometimes kills healthy brain tissue.
Radiation therapy attempts to destroy tumor cells by using high-energy radiation focused onto the tumor to destroy the tumor cells' ability to function and replicate. Radiosurgery is a nonsurgical procedure that delivers a single high dose of precisely targeted radiation using highly focused gamma-ray or X-ray beams that converge on the specific area or areas of the brain where the tumor or other abnormality is located, minimizing the amount of radiation to healthy brain tissue. Equipment used to do radiosurgery varies in its radiation source; a gamma knife uses focused gamma rays, and a linear accelerator uses photons, while heavy-charged particle radiosurgery uses a proton beam. Tomotherapy is a type of radiotherapy in which radiation is delivered in a highly precise and individualized manner that minimizes radiation exposure to healthy tissue; it has also been used to treat brain cancer.