Electron therapy

Radiopaedia • CC-by-nc-sa 3.0 • de

Electron therapy, or electron beam therapy, is a form of radiotherapy which is used to treat superficial lesions. Electron beams are rapidly attenuated by soft tissue and thus can only treat to a depth of a few centimeters (typically 0-3 cm), compared to megavoltage x-rays which are much more penetrating. Suitable targets include:

Electron therapy is performed with a medical linear accelerator by withdrawing the x-ray target from the beam path. Unlike photons, electrons are widely scattered by air before reaching the patient. This necessitates the use of 'electron applicators' which are specially designed diaphragms which collimate the electron beam at the skin surface.