Magnetic resonance imaging MRI


The human body is composed of a large number of atoms of various substances. The magnetic moments (spins) of these atoms align in the direction of a strong magnetic field. During the application of a "exciting" radiofrequency pulse, the spins of the atoms are disturbed, and after the pulse ends, the spins return to their "aligned position". As they return to this position, the atoms emit various signals. By measuring these signals, their appearance can be displayed on a monitor using various computational algorithms.

A radiology technologist performs the scans, which are then evaluated by a radiologist.

Before each MRI examination, the patient must sign an informed consent form.

FAQ

MRI

MRI

Are there any contraindications when the examination cannot be performed?

Our department cannot perform examinations on patients with pacemakers (even MR "compatible" ones).
It is very important to inform the radiology assistant about all devices you have in your body (insulin or infusion pumps, electrodes, pacemakers, clips from previous surgeries, prostheses, piercings, magnetic false eyelashes, hair extensions, etc.). In some cases, it is not possible to perform the examination at our clinic for these reasons.

How does the MRI scan work? Are medications administered?

The patient lies down on the examination table and lies down according to the instructions of the staff. You must remain still during the image capture so that the image is not blurred. It is sometimes necessary to use contrast agents, which may be given to the patient intravenously, orally or in the cavity before or during the examination to increase diagnostic accuracy. You will be asked to sign an informed consent form. If the contrast agent is intravenous, an intravenous cannula will be inserted, most commonly into a superficial vein in the elbow area. In these cases, it is advisable to drink plenty of fluids in the hours after the MRI scan to help the contrast medium be excreted more quickly in the urine. Patients suffering from claustrophobia may need sedation before the examination. This preparation is carried out by the anaesthetist using a standardised procedure.

How to prepare for an MRI?

For examinations without sedation or other special preparation (liver, kidney, pancreas, enterography) it is not necessary to go on an empty stomach. For examinations where the patient's cooperation is required during the examination (liver, kidney, pancreas, enterography), analgosedation is not possible.

How is the examination carried out?

The radiology assistant will give you instructions on the procedure, disposable clothing will be provided if necessary, it is essential that you leave all metal objects such as jewellery, coins etc. in the cabin. If intravenous administration of a contrast agent or sedation is required, an intravenous cannula will be inserted, usually into a superficial vein in the elbow area. All patients requiring sedation are monitored throughout the examination with a pulse oximetry monitor. The patient enters the tunnel of the machine and the examination is started. The examination is accompanied by noise, which can be unpleasant. For this reason, we offer patients hearing protectors to minimize this discomfort. It is important that the patient is completely at ease so that good quality images can be obtained. The length of the examination varies depending on the type of examination you require. It will usually not exceed 45 minutes. If you need sedation, you will be monitored by an anaesthetist who will monitor your vital signs using equipment such as a heart rate monitor or oximeter.

Why do I wear earmuffs during the examination?

The production of radiofrequency pulses, which are used to obtain MR images, is accompanied by noise that can be unpleasant. For this reason, we offer patients hearing protectors that minimize this discomfort. In some cases, you will be asked to wear headphones into which you will receive instructions to hold your breath.

How much radiation will I be exposed to?

MRI does not use ionising radiation. It uses electromagnetic waves that do not damage the body.

Can I have an MRI if I am claustrophobic?

Claustrophobic patients should be specially prepared for this procedure, e.g. use anxiolytics. You will be given a signal balloon in your hand, which will trigger an alarm. If despite everything the feeling of claustrophobia persists, you squeeze the balloon in your hand and the procedure stops immediately. If all these measures fail, the procedure will be performed under analgosedation. We do not perform examinations under general anaesthesia at our clinic.

Preparation List

Preparation for MR examination

For each MRI examination, it is necessary to bring a properly filled-out request form specifying the required examination and expected benefits. If there is previous documentation available (not just images) related to the current examination, it is advisable and beneficial to bring it along (a simple copy of a report, for example).
Most examinations do not require any special preparation. To expedite the procedure, we recommend removing all jewelry and metal accessories and wearing clothing without metal (such as elastic waistband pants, leggings, cotton shirt, sports bra, etc.).

How is it carried out

MR examination process

The patient submits a request for examination upon admission to the department (and presents their insurance card) and reads and completes the informed consent for the examination. The examination is conducted by a skilled radiology assistant under the supervision of a radiologist.
Before the examination, it is necessary to remove clothing with metal components, particularly zippers, buttons, buckles, underwires, jewelry, removable prosthetics, etc.
In cases requiring contrast agent administration, an anesthesiologist inserts an intravenous cannula. The contrast agent is administered at the appropriate stage of the examination.
Most examinations are performed lying on the back, and in specific cases (e.g., MR enterography, certain upper limb joints), lying on the stomach.
During the examination, it is essential for the patient to remain still. Patients may receive instructions to hold their breath, inhale, or exhale as needed.
The total duration of an MRI examination can range from 15 minutes to 1 hour, depending on the required imaging sequences and whether contrast agent is needed.
The acquired imaging documentation is digitally processed and subsequently evaluated by a radiologist who prepares the final report – description. The description is then typically sent to the referring physician. In uncomplicated cases, the report is usually available within a week.

Number of Centers with Services

Clinic

Affidea Brno

Křižíkova 3011/68i
612 00 Brno - South Moravian Region
+420 534 008 354
Polyclinic

Affidea Praha

Šustova 1930/2
148 00 Prague - Capital city
+420 267 090 811
Clinic

Affidea Brno

Křižíkova 3011/68i
612 00 Brno - South Moravian Region
+420 534 008 354
Polyclinic

Affidea Praha

Šustova 1930/2
148 00 Prague - Capital city
+420 267 090 811