Magnetic resonance imaging is often referred to as MR or MRI. In medicine, magnetic resonance imaging is a so-called imaging procedure.
What is magnetic resonance imaging?
Magnetic resonance imaging (MRI) is an imaging procedure. It is mostly used for diagnosis and to visualize the structure and function of tissues and organs. This means that magnetic resonance imaging can be used to obtain image data on body structures or organs. Since the physical principles of magnetic resonance imaging are based on those of so-called nuclear magnetic resonance, magnetic resonance imaging is also sometimes referred to as magnetic resonance imaging. The way magnetic resonance imaging works is based on magnetic fields, which in turn excite various atomic nuclei in the body of living beings. This excitation is then used by magnetic resonance imaging to collect data. The collection of image data is made possible, among other things, by different textures and compositions of different types of tissue. In this way, magnetic resonance imaging can be used to obtain image contrasts. The technique of magnetic resonance imaging was developed in the 1970s.
Function, effect, and goals
Magnetic resonance imaging is used primarily in the field of medical diagnostics, i.e., in diagnosing functional disorders or diseases. With magnetic resonance imaging, for example, it is possible to generate so-called sectional images or slice images. Body structures or organs can be viewed in digital “slices”. This possibility of magnetic resonance imaging makes it possible to detect changes in the tissue of a living organism. Depending on the field of application of magnetic resonance imaging, different methods can be used. For example, in addition to creating slice images, it is also possible to show processes in the body on film. In this way, for example, blood flow can be depicted or the function of organs such as the heart. This form of magnetic resonance imaging is also known as real-time MRI. Real-time MRI is also used, among other things, to assess the function of joints in motion. If a patient’s vascular system is to be examined more closely with the aid of magnetic resonance imaging, magnetic resonance angiography (MRA) is a suitable procedure. With its help, blood vessels such as veins or arteries can be visualized. This form of magnetic resonance imaging occasionally involves the use of MRI contrast agents, which help to make some images clearer. As a rule, three-dimensional image data are acquired during MRA. Functional magnetic resonance imaging (also known as fMRI or fMRT) is one of the methods used to visualize structures of the brain. With this form of magnetic resonance imaging, it is possible, among other things, to view activated brain areas in pronounced spatial resolution. If a patient’s tissue perfusion is the focus of diagnostic observation, perfusion MRI can be used, for example. Finally, if nerve fiber connections are to be virtually reconstructed, the use of a form of magnetic resonance imaging known as diffusion imaging is appropriate. This method can be used to spatially visualize movements of water molecules in the body. The background is that in some diseases of the central nervous system, for example, the movements of these molecules are found to be altered.
Side effects and dangers
Magnetic resonance imaging works without generating any radiation that is harmful to the body, such as X-rays or other ionizing radiation. In cases where so-called contrast agent is used as part of magnetic resonance imaging, this agent can cause various side effects. Contrast agents are used in magnetic resonance imaging to show various physical structures more clearly. In some patients, contrast media can cause allergies or intolerances. However, such allergy is quite rare. Symptoms of intolerance to contrast media used in magnetic resonance imaging include headaches or nausea, for example.Magnetic resonance imaging can pose risks, for example, to patients who carry metal in or on their bodies. For example, metal splinters in the body can change their position under the influence of magnetic resonance imaging, which can endanger body structures. The use of magnetic resonance imaging is also limited in people who wear a pacemaker. This is because pacemakers can be destroyed by the effects of the magnetic forces released during magnetic resonance imaging. During the performance of a magnetic resonance imaging, there is a high level of background noise due to the large magnetic forces, which some patients find unpleasant. In addition, the small diameter of the examination tube used in a magnetic resonance imaging scan can occasionally cause feelings of trepidation or claustrophobia.