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Ionising radiation

Environmental Radioactivity - Medicine - Occupational Radiation Protection - Nuclear Hazards Defence

Ionisierende Strahlung


In 1895 Wilhelm Conrad Roentgen discovered a new kind of radiation that was named after him later on (Roentgen rays, also referred to as X-rays in many languages). Roentgen’s epoch-making discovery was enthusiastically celebrated. X-rays permitted insights into the human body without surgery for the first time ever, thus marking a dramatic progress in medical diagnostics. Nowadays X-ray diagnostics is a widespread and frequently used imaging procedure.

X-ray photograph

X-ray diagnostics – the procedure

In X-ray diagnostics, a difference distinction is made between three techniques: radiography, fluoroscopy and computerized tomography (CT).

Benefit and risk of X-ray diagnostics

X-ray diagnostics is chosen by the doctor when other procedures such as laboratory tests, ultrasound or endoscopy would fail to provide a precise diagnosis. Radiology often is the first procedure to permit or confirm diagnosis or to specify findings.

X-ray record card (Röntgenpass)

X-ray record card (Röntgenpass)

The personal Röntgenpass (X-ray record card) is an important tool to avoid unnecessary duplications of X-ray procedures. It also allows reference to previous X-rays procedures. Therefore the BfS recommends to continue using the Röntgenpass.

Frequency of X-ray examinations,  CT and  MRT examinations

X-ray diagnostics: Frequency and radiation exposure

X-ray examinations always involve some, albeit low, radiation risk. Therefore, the number of examinations performed and the related radiation exposure incurred by the general public in Germany are regularly assessed. These data are annually recorded, analysed and evaluated.

Two mammography images side-by-sideSource: Dr. med. H. Junkermann

The German Mammography Screening Programme

With about 70,000 newly diagnosed cases per year, breast cancer is the most common type of cancer found in women in Germany. In spite of major progress in the field of breast cancer treatment, about 17,000 women die from this disease every year.

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