Introduction
In magnetic resonance imaging (MRI), imaging is performed with the aid of a strong magnetic field. For this purpose, the patient is placed on a table and pushed into a closed tube with a diameter of 50 to 60 cm. Depending on the problem, different parts of the body may be inside the tube while others are outside.
Especially when examining the upper body (head, cervical/chest spine, shoulder, heart, lungs), the head is often inside the tube. This is a serious problem, especially for patients with claustrophobia. For this reason, new MRI devices have been developed over the last decades, which can be used if necessary.
In addition to a wider diameter (up to 70 cm), these devices are significantly shorter, which is why there are only a few body sections inside the tube, except for the body region to be examined. In addition, so-called open MRI devices have been developed. Here, the magnetic field is generated by a C-shaped magnet, which is open on one side. The patient has a 320° view during the examination. However, the examination in an open MRI is not possible for all questions and is only partially paid for by health insurance companies.
MRI of the head
When examining the head in a closed MRI tube, the head is inside the tube. One is pushed into the tube on a table, head first. The patient only sees the inside of the tube during imaging and is not allowed to move during the examination.
In addition, the head is additionally fixed with a kind of grid (coil). If claustrophobia is known to occur, the patient should inform the physician in a prior consultation. Often questionnaires are filled out before the examination, in which the claustrophobia can be noted.
The doctor can then administer a sedative (Dormicum) to the patient during the examination. In rare cases, a short anaesthetic with Propofol may also be indicated. In addition, the patient is given a button in his hand with which he can stop the examination at any time.
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