radiotherapy

Synonyms

  • Radiation oncology
  • Irradiation
  • Tumor irradiation

definition

Radiation therapy is the treatment of benign and malignant (cancer) diseases using high-energy radiation.

The medical field of radiation therapy exists independently as a third radiological specialty alongside diagnostic radiology and nuclear medicine.

Physical basics of radiation therapy

The term radiation stands for a physical form of energy. Visible light is a known form of radiation. The term radiation combines a large number of different types of radiation.

In principle, wave radiation (photon radiation) can be distinguished from particle radiation (corpuscular radiation).

The Wave radiation contains many small energy carriers, the photons. The special thing about the photon is that it has no mass of its own. In the broadest sense it is pure energy in the form of electromagnetic waves.

In contrast to this, the energy carriers have Particle radiation its own mass. One example is the electron beam, which is composed of many small electrons.

Both particle radiation and wave radiation continue to be collective terms that combine physically different types of radiation in radiation therapy.

Photons

Individual photons can be physically differentiated based on their wavelength. The wavelength describes the distance that exactly one wave traverses from the beginning to its end point. The self-energy and the possibilities of the interactions depend strongly on the wavelength of the wave radiation.

Particle beams differ in the type of particle. All will be in the radiotherapy used.
Examples for this are:

  • Electron beams
  • Proton beams
  • Neutron beams
  • Heavy ion beams

Electron beams

Electron beams (negatively charged particles from the atomic shell)

Proton beams

Proton beams (positively charged particle from the atomic nucleus)

Neutron beams

Neutron beams are uncharged particles from the atomic nucleus.

Heavy ion beams

Heavy ions can e.g. consist of carbon ions C12.