Brachytherapy comprises interstitial therapy and intracavitary therapy. To facilitate delivery of interstitial therapy, a radioactive material for example gold-198, iridium-192 or iodine-125 is put in using a surgery in the surrounding area. The radionuclide is inserted as an element of strands using tiny preserved bud vases or in detachable needles. These stands are called seeds.
In the intracavitary therapy the radioactive source is placed closest to the tumor inside a body cavity. For this process radioactive materials like radium, cesium-137 or phosphorous-32 are used. Uterus, cervix, and vaginal cancers are managed using intracavitary therapy.
Dispensation of radioactive materials into the bloodstream is one more variety of radiotherapy. For this method of radiotherapy iodine-131 is used to treat hyperthyroidism and thyroid carcinoma. Iodine-131 is dispensed orally in hyperthyroidism and this material mixed with blood and mounts up in the thyroid gland. This material irradiates the tissue in the thyroid and so reduces the activity of the gland. Iodine-131 is also absorbed by thyroid tumors. In treating thyroid carcinoma, iodine-131 is used after partial or total thyroidectomy to inactivate any residual thyroid tissue and to treat metastases.
The unit of radiation dispensation measurement is gray or in short Gy. A gray is equivalent to 100 rad i.e. radiation absorbed dose. Tumors and body tissues are categorized in the same way as radiosensitive and radioresistant as per the number of gray obligatory to kill or injure cells.
Examples of radiosensitive organs are the ovaries and testes. Radioresistant organs are for example pituitary gland and adrenal glands. These glands are disposed to the effects of radiation. Lymphomas are in the main radiosensitive, but sarcomas are by and large radioresistant.
Side Effects of Radiation Therapy:
Radiotherapy even if it perhaps moreover a painkilling or restorative agent is able to create objectionable side effects on customary body tissues that are by the way irradiated. Some of these snags are reversible by the time and recovery takes place almost immediately after the period of radiotherapy is over. These acute reversible effects may include:
1. Mucous membrane ulceration. The another names for this condition is mucositis for example in the pharynx, mouth, vagina, bladder, or small and large intestine. Xerostomia i.e. dryness of mouth takes place after radiation to the mouth or pharynx.
2. Nausea and vomiting as a reaction to radiotherapy to the brain or gastrointestinal organs.
3. Bone marrow suppression or myelosuppression, with leukopenia and thrombocytopenia.
4. Alopecia i.e. baldness.
With higher does of radiotherapy these impediments can be linked with everlasting organ damage. Besides, radiotherapy delivered in therapeutic doses may produce chronic wound to any body organ that happens to be in or near the path of the radiation beam. Chronic side effects depend on the site of treatment delivery and can include pericarditis, pneumonitis, vasculitis i.e. inflammation of the blood vessels, and fibrosis of the skin and lungs.
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