Background information magnetic resonance imaging

With the help of magnetic resonance imaging (MRI) it is possible to display cross-section images of anatomic conditions of the human body and their variants or pathological changes.

The nuclei of the hydrogen atom in our body form the basis for this method. An artificially generated magnetic field lines them up in an orderly way and finally the nuclei are set into vibration by means of a radio signal. Once the signal is switched off, the nuclei “turn back”, leaving electric impulses, which can be read out by a magnetic resonance receiver and subsequently converted into a visual representation.

Depending on the nature of the tissue, the impulses differ from one another, thus producing correspondingly various structures on the image – a perfect opportunity, for instance, to differentiate between the healthy and diseased tissues.

MRI advantages:

• No radiation exposure
• In many cases, an MRI diagnosis is of great significance; in many areas, MRI is clearly preferable to other methods (e.g. CT). Many problems can even be solved with the help of MRI.

MRI disadvantages:

• In some cases it is not feasible (see above)
• A longer period of time is required for an examination (e.g. if compared to CT)
• There is a problem with claustrophobic patients

An MRI scan is carried out in a lying position. Depending on which body region is to be examined, your whole body or just a part of it will be placed inside the device. In many cases, your head will, however, remain outside, so you are sure not to find the narrowness to be too unpleasant.

Depending on the problem, it may be necessary to inject a contrast medium.

Please do not be surprised by loud noises, produced by the magnetic resonance tomograph– this results from using the magnetic fields (see above). Earphones with relaxing music or another kind of ear protection may help.

The duration of an MRI examination depends on the exact examination requirements and, as a rule, varies between 5 and 30 minutes.

MRI is absolutely painless and does not expose you to radiation.

Please bear in mind that inside the MR device you are exposed to a strong magnetic field. It is vital that you remove all metallic objects (e.g. wrist watches, hearing aids) in advance of an examination and let us know, if there are any metal parts inside your body (e.g. stents, insulin pumps and also tattoos). Cardiac pacemakers and inner ear prostheses can be damaged in a magnetic resonance scanner – in such a case, it may be necessary to use another examination method.

A cardiac pacemaker remains the main reason, why the examination cannot be carried out – even if there are more and more clinics that still carry out MRI – however, this should be done by a very experienced specialist and only in exceptional cases.

As a rule, such implants as vascular stents (also in the heart), cardiac valves, vascular shields and also joint prostheses or metal components of the bones, e.g. after a bone fracture, do not cause any problems.

Be sure to inform us, if there are any “foreign objects” in your body after medical interventions, or if there are metal structures inside your body due to any other reasons (e.g. shell splinters or metal splinters after e.g. an accident at work).

With regard to tattoos and piercings, each case is treated individually. Please contact our medical staff before the examination.

If you suffer from claustrophobia, inform our medical staff about it as early as possible. You are welcome to test in advance, what it feels like to lie inside the machine. The patients are often pleasantly surprised how “open” the device really is. If a sedative is required, you should, however, make sure not take an active part in public traffic on this day (e.g. no driving a car). In such a case, let somebody drive you to the examination or pick you up.

If you have questions concerning this matter, you are welcome anytime to get information in advance from one of our technical assistants or doctors.

Recently there have been a great number of reports on damages/side effects that are probably connected with the administration of contrast media during MR diagnostic procedures. This particularly affects patients with impaired renal function. For this reason, please contact our medical staff before the examination, if you have already been diagnosed with a kidney disease or “renal insufficiency”. In this case it will be the best possible solution, if your referring doctor / family doctor determines the so-called creatinine level in the blood and you bring the result with you.