Magnetic resonance imaging (MRI) is a radiation-free examination, that produces very precise images of the internal structure in the human body with high spatial resolution.
An MRI is an examination that produces detailed images of the inside of the body, which are converted into high precision two- or three-dimensional pictures. This technique is based on the fact that our tissues are made up of 70% water and the images are obtained through a powerful magnetic field, using different radiofrequency waves (hence the noise you may hear during the examination).
The examination lasts between 15 and 25 minutes on average, up to 45 minutes in some cases, depending on the anatomical region to be explored and the reason for the examination. The operator will accompany you to the changing cabin and will show you which clothes to remove before the examination. For more comfort, do not hesitate to choose light, loose-fitting clothes, without metallic microfibers. As the MRI is a big magnet, you will have to leave all metallic objects in the cabin (jewellery, watch, transdermal patch, belt, telephone, credit card, tram/bus ticket, hair clips, etc.).
During the examination, you will lie on a sliding bed inside a tunnel housing the magnetic field. The machine makes a little noise, due to the electrical pulses received by the gradient coils generating a magnetic field, and to attenuate this noise, we will provide you with protection (headphones with music and/or earplugs). The table slides through a fairly wide tunnel in the MRI machine, open at both ends. To achieve optimal imaging, it is extremely important to remain as still as possible. Breathe calmly and normally and follow the instructions given to you. To avoid blurred images, you will be asked not to move during the examination. You may need to hold your breath for short periods of time. For some examinations and only when necessary, an infusion may be given to you for the intravenous administration of gadolinium-based contrast material.
Before your examination, you will be asked to complete a questionnaire to evaluate any possible contraindications to MRI. These include implanted devices such as a pacemaker, certain heart valves, hearing aids, any elements with metal components near the eyes or in the head (metal splinters from welding, etc.) and also in the first trimester of pregnancy. Some of them may in fact be considered incompatible with MRI, while others will simply require an adaptation of the magnetic field of the MRI. If it is impossible to perform an MRI, the radiologist will refer you to another type of examination (a CT scan for example).
At the Medical Imaging Facility (GIE) of the University Hospital Institute of Strasbourg, we have a Siemens 3 Tesla MRI. It allows us to achieve high throughput of diagnostic performance through its high-quality images.
Special cases: your doctor prescribed an entero-MRI. This examination takes about 45 minutes. Fasting (6 hours) is mandatory prior to your exam. You will be asked to drink approximately 1 L of a liquid (which will be prescribed to you) which will slightly distend your bowel. A small infusion will be given to you to allow an injection of a contrast product throughout image-acquisition. Scheduling your appointment should allow sufficient time for this preparation.
What to bring
Before you undergo the examination, you will be asked to fill out an MRI screening form.
Preparation
There is no special preparation for routine examinations. However, for certain specific exams, you will be given specific preparation instructions when making your appointment:
How much time will I spend at the Medical Imaging Facility (GIE)?
You will need to allow approximately one hour between your arrival at our Imaging Facility and your departure, depending on the type of examination. Naturally, your waiting time may vary within 20 minutes, but certain more specific exams may take longer.
In Case of Emergency
During the Medical Imaging Centre’s opening hours, depending on the degree of urgency, radiologists can accept where possible, to perform your MRI in an urgent/semi-urgent situation: do not hesitate to contact our secretariat.
