Contrast media

In order to be able to implement special medical examination procedures sensibly and as efficiently as possible for those affected, various aids are required. These chemical substances include in particular the so-called Contrast media.

What are contrast media?

Contrast media are substances that are not used directly for the treatment of diseases and for the elimination of the symptoms that occur. The excellent purpose of contrast media is to aid in the detection of diseases and abnormalities in organs.

The use of contrast media in medicine is mainly limited to the medical technology methods known as imaging processes. The contrast media are used in ultrasound and X-ray diagnostics as well as in magnetic resonance tomography. Because of the existing need for contrast media, these techniques are also referred to as contrast media displays.

Various contrast media must have very specific properties and should not have any effect on the organism. They are eliminated naturally from the body.

Application, effect & use

In addition to X-ray diagnostics and sonography, state-of-the-art procedures such as magnetic resonance tomography are not without it Contrast media carried out. Contrast media make it possible to better visualize individual morphological structures.

The physical laws of optics are used for contrast media. In this context, the aim is to use very special chemical particles in the contrast agent to darken certain anatomical structures. By creating shadows, it is possible to specifically modify information that is sent out by the examination device. This is the basis for increasing the image quality of the diagnostic contrast agent displays.

The individual contrast media show different light and radiation absorption. In addition, the composition of the contrast media differs. They differ in their molecular weight, osmolarity and viscosity. Medical technology processes make use of this and work with various contrast media in order to achieve the best possible quality of the images.

Contrast media, which are ideally suited for MRI, for example, are based on the creation of a density difference in an artificial way. It is about the optical influence of metal ions, which have a magnetic nature.

Substances used

Not all used Contrast media are based on the same principle. Contrast media in radiology have either a high or a low density and are referred to as X-ray negative or X-ray positive substances.

For the patient or the patient, the contrast media appear as liquids that are introduced into the organism either via the mouth or via an injection. In the medical field, however, numerous contrast media are administered which differ from one another in terms of their chemical and physical structure.

In X-ray diagnostics, contrast media are administered in the form of suspensions made from barium sulfate. In addition, many X-ray contrast agents contain iodine.

In the area of ​​examinations using ultrasound, completely different contrast media are preferred. In medical specialist circles, these contrast media are known as so-called echo contrast intensifiers. The contrast media usually contain air bubbles or a well-tolerated gas and are mostly similar to a foam. The internal organs are "inflated" so to speak, which means that better ultrasound examinations can be carried out with these contrast media.

The extra- and intracellular contrast media have meanwhile proven themselves in magnetic resonance tomography. The latter group of contrast media is rarely chosen. The particles known as superparamagnetic iron particles belong to this class of contrast media.

In addition, substances are administered that form a chemical bond with manganese. Extracellular contrast media are typical imaging aids in MRI. In contrast to the intracellular (intra = inside) contrast media, these contrast media move outside the organ cells. These contrast media contain gadolinium ions and accelerate the magnetization of the water in the tissues.

Risks & side effects

Generally they are modern Contrast media harmless and are not always stored in the organism. Therefore, health consequences caused by contrast media are excluded. As a rule, the contrast media are excreted in the normal way unnoticed and do not cause any symptoms. Some people may develop an allergy or an intolerance to contrast media. Other side effects of orally administered contrast media can include mild diarrhea or nausea. However, this is mostly due to the large amount of liquid in which the contrast agent is dissolved.