Dictionary

radiation oncology The medical specialty that is involved in the use of radiation (X-rays, gamma rays, or electrons) to treat cancer.

radiation pneumonitis See pneumonitis, radiation.

radiation therapy The use of high-energy rays to damage cancer cells, stopping them from growing and dividing. Like surgery, radiation therapy is a local treatment that affects cancer cells only in the treated area. Radiation can come from a machine (external radiation) or from a small container of radioactive material implanted directly into or near…

radiation therapy, external Radiation therapy in which the source of radiation is a machine outside the body.

radiation therapy, internal Radiation therapy in which a small container of radioactive material is implanted in the body, in or near the cancerous tumor.

radiation therapy, interstitial A form of radiotherapy in which tiny radioactive “seeds” are implanted directly in the affected tissue with a needle-like instrument. Interstitial radiation therapy has been used in the treatment of prostate and other cancers.

radiation therapy, stereotactic The use of a number of precisely aimed beams of ionizing radiation, each coming from a different direction and meeting at a specific point, to deliver radiation treatment to that spot.

radical dissection Surgical removal of not only affected tissue, but also nearby tissue that may be covertly affected.

radical neck dissection Often called a “radical neck,” a surgical procedure that involves the removal of a tumor from the neck with an additional margin of seemingly normal tissue of at least 2 cm together with the removal of the lymph nodes from the neck.

radiculitis See radiculopathy.

radiculopathy Any disease of the spinal nerve roots and spinal nerves. Radiculopathy is characterized by pain that seems to radiate from the spine, extending outward to cause symptoms away from the source of the spinal nerve root irritation. Causes of radiculopathy include deformities of the discs between the vertebrae. Patients with diabetes can be affected…

radioactive Emitting energy waves due to decaying atomic nuclei. Radioactive substances are used in medicine as tracers for diagnosis and in treatment to kill cancerous cells.