How does radiotherapy work?

Therapy planning and radiation technology

A radiotherapy consists mainly of the therapy planning and the realisation of this plan.

In the run-up of the radiotherapy and within the planning phase it will be determined exactly for each patient, which radiation technology the radiotherapy equipment will use. For example we can now guide a beam "around the bend" in order to either improve the exact treatment of concave or convex structures or to improve their careful treatment.

The result is that you can treat a tumour with a higher dose and at the same time protect the healthy vicinity better. This will increase the probability that the tumour can be removed and healing can be achieved with less side effects.

Example: Radiotherapy of the prostate in the past and nowadays – optimal protection of the intestine.

Linear accelerator

How does a so-called linear accelerator work, i.e. the equipment used to carry out the radiotherapy?

A linear accelerator does not operate with radioactive material!
A linear accelerator will initially produce minute electrically charged particles, the electrons. These electrons will be accelerated by using a magnet to almost the speed of light (since the name of the equipment).

At the end of the acceleration path they will emerge from the equipment as a therapy beam or will hit a wolfram plate in the equipment. This collision will create so-called photons that due to their physical characteristics will be suitable to treat regions that lie deeper beneath the skin.

So while one will treat superficial conditions with electrons, most conditions will be treated using photons. Light consists of photons, however it has a lower energy than the rays used during therapy.

Before the ray emerges from the device its form will be shaped by various procedures that the physician has determined during the therapy planning. This will ensure that only the specific region to be treated will be treated.