Definition Introduction
Magnetic resonance imaging (MRI) or magnetic resonance imaging is an imaging procedure that does not involve the harmful radiation exposure associated with X-rays or CT. The examination produces sectional images of the human body. The basis for the principle of MRI is the special property of hydrogen atoms, which also occur in the human body, to have their own angular momentum (nuclear spin).
As a result, they generate their own very weak magnetic field, through which they can be influenced from outside by a large magnet like small bar magnets. Such a large external magnet is built into the magnetic resonance tomograph. The device emits an electromagnetic signal and then stops the time until the particles have realigned themselves.
Depending on the tissue, the hydrogen particles are deflected for a longer or shorter time, so that it is possible to differentiate between fatty tissue and blood, for example. From the incoming electrical signals, the device generates sectional images of the body’s interior, on which pathological changes can be depicted. As described above, the patient is not exposed to radiation during an MRI examination as is the case with CT or X-rays, since the applied magnetic field is completely harmless to the body.
MRI also offers a higher resolution than computed tomography or conventional x-rays. Especially soft tissues such as muscles, supporting tissue and internal organs can be assessed very precisely by means of a magnetic resonance examination. Bony structures, on the other hand, can be depicted far better with a computed tomography examination than with a magnetic resonance imaging.
However, since an MRI of the cervical spine has a longer application time (approx. 20min) than a CT, its importance in an absolute emergency is secondary. Also, an MRI examination of the cervical spine is much more expensive than a computed tomography.
Furthermore, due to the limited number of devices, it is more difficult to make an appointment. There can be several reasons (indications) for a magnetic resonance imaging examination of the cervical spine. On the one hand, an MRI examination can detect or rule out a herniated disc of the cervical spine.
The spinal cord can also be examined for acute or chronic damage, just as the bone marrow can be examined for inflammation or tumors. The vertebral bodies (Corpus vertebrae) as bony structures and the spinal canal (Canalis vertebralis) of the cervical spine formed by them can also be examined. Thus, active wear and tear of vertebral bodies or intervertebral discs can be detected.
In addition, vascular malformations can be visualized. Tumors of the spinal cord skin (meningiomas) or metastases in vertebral bodies can also be detected. Furthermore, a constriction of nerves and also inflammatory processes as in the context of rheumatic diseases or a MS disease can be displayed.
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