External beam radiotherapy Health Dictionary

A treatment which uses atomic particles and high energy rays to destroy cancerous cells.... radiotherapy

Compression of the outside of the sternum and ribs, effectively emptying and filling the heart to push blood through arteries to supply oxygen to the body - particularly to the brain.... external cardiac compression

See “validity”.... external validity

Treatment of a cancerous tumour by inserting radioactive material into the growth or into neighbouring tissue. Using this method, also called brachytherapy, radiation can be targeted at the diseased area.

Radioactive material (usually artificial radioisotopes) contained in wires, small tubes, or seeds is then implanted into or near the diseased tissue under general anaesthesia. The material is left in place for variable amounts of time depending on the radioactive substance and the tumour being treated. (See also intracavitary therapy; radiotherapy.)... interstitial radiotherapy

(AED) a type of external *defibrillator that can analyse the heart rhythm it detects and advise via voice prompts on therapy to be given according to the latest guidelines. In cases of ventricular fibrillation, some defibrillators will make decisions on delivering electric shocks and do so after issuing appropriate warnings to the attending health-care professionals.... automated external defibrillator

see image-guided radiotherapy.... cone beam

(EECP) an experimental treatment for patients with intractable angina. Specially designed inflatable trousers are inflated rhythmically in time with ventricular *diastole. Theoretically this imparts additional energy to the circulating blood volume when the heart is relaxed, and this may improve blood flow down severely narrowed coronary arteries. It is also claimed to have beneficial effects on blood flow to other organs. Despite promising clinical trials, this technique has not been widely adopted.... enhanced external counterpulsation

an apparatus consisting of a rigid frame that connects pins passed through the skin into the bone above and below a fracture. This immobilizes the fracture, and is used particularly to treat some compound fractures. An external fixator is also used for *limb lengthening.... external fixator

(IGRT) the process of imaging during a course of radiation treatment to verify the internal position of the target in comparison to the initial planning scan. This enables adjustment of *treatment fields to improve coverage and allows the use of smaller treatment volumes. The possible methods for IGRT include cone beam CT, *tomotherapy, *cyberknife, and ultrasound and kilovoltage X-rays of implanted fiducial markers.... image-guided radiotherapy

(IMRT) radiotherapy using multiple beams with variable intensity across each field, resulting in dose distributions that can fit to concave shapes and thus reduce dose to surrounding healthy tissues and organs. It can be used to treat a wide range of cancers and can enable safe delivery of higher doses to tumours.... intensity-modulated radiotherapy