Water phantom
A water phantom is with distilled water filled plexiglass tank , the representative of living tissue for testing in the radiation therapy used electron linear accelerators is used. Water has a permeability comparable to that of living tissue for ionizing radiation from the sources used.
Situation in Germany
Checks using a water phantom must be carried out approximately every three months in accordance with statutory regulations to ensure that the radiation output set on the therapy device for a certain point in the room, in the body or in the water phantom and provided according to the radiation plan there is also accurate this strength occurs.
The verification using a water phantom is carried out and documented by the medical physicist employed in the radiological practice according to the Radiation Protection Ordinance and the X-ray Ordinance or by external test engineers.
In Germany, according to DIN 6448, controls of the depth dose gradients and transverse profiles are carried out in a three-dimensional water phantom . These tests are necessary in the context of radiation therapy, as the dose measured using the water phantom must match the dose calculated by the radiation planning system. The content of the water phantom is preferably distilled water, since it gives results comparable to living tissue better than ordinary water. A mobile dosimeter is installed in the water , which covers the entire area and carries out a dose measurement. The collected measurements are then plotted graphically in the depth dose profile and in the cross profile.
literature
- Hanno Krieger: Radiation sources for technology and medicine . Vieweg + Teubner; 1st edition (August 2005) ISBN 978-3835100190
