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Ionising radiation

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

Ionisierende Strahlung


Different procedures are used to detect a disease. The patient’s medical history, also referred to as anamnesis, is compiled first to establish the diagnosis. Anamnesis is the basis of all further diagnostic procedures. These include not only physical examinations (for example palpation) or laboratory tests (for example blood) but also imaging procedures such as diagnostic X-ray and ultrasound examinations. In the following, imaging procedures will be described in more detail.

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).

Medical application of radiation during pregnancy

If a pregnant woman is exposed to radiation, then malformations and developmental disorders may occur in the unborn child. In addition, the child has an increased risk of developing cancer or leukaemia. For this reason, there are appropriate provisions for protecting the unborn child in the radiation protection law. Accordingly, before applying ionising radiation in medical diagnostics or therapy, the examining physician has to ask every woman of reproductive age whether she is or may be pregnant.

Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) is one of the most important and meaningful imaging techniques successfully used in diagnostics for a variety of issues. In contrast to computed tomography (CT), MRI does not involve ionizing radiation but different magnetic and electromagnetic fields. MRI is not associated with health risks to the patient when current safety recommendations are observed. The following article gives a brief introduction to MRT and illustrates relevant safety aspects.

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.

Scintigraphy of a thyroid glandSource: Technical University of Munich, Clinic and Policlinic of Nuclear Medicine, Klinikum rechts der Isar

Diagnostic nuclear medicine

Patients in diagnostic nuclear medicine are given radioactive pharmaceuticals (radiopharmaceuticals) accumulating in organs and tissues in varying concentrations, depending on the pharmacological properties of the compound administered. Due to their radioactivity, the location and time of distribution within the body is detectable using proper measuring equipment, and thus can be visualised.

Ultrasound Diagnostics (UD)

Sonography is a frequently used imaging technique for medical diagnostics. Ultrasound diagnostics uses acoustic waves and not ionising radiation.

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