Magnetic resonance imaging: what is it?

THE MRI it is a radiological examination available to doctors and patients, as well as traditional radiography, tomography or ultrasound. The analysis made by means of magnetic resonance aims to study the organs of the human body in a precise way until reaching a diagnosis.

Magnetic resonance imaging

Magnetic resonance imaging uses a technique based on the atoms of some molecules under the action of radiofrequency.

Principle of magnetic resonance imaging

Magnetic resonance imaging uses modifications generated by a magnetic field, sent by the machine, in the nuclei of the hydrogen atoms present in the organism (nuclear magnetic resonance). This test is painless, non-invasive and does not use X-rays.

Magnetic resonance imaging technique

The technique involves the use of a very strong magnet that generates a magnetic field responsible for generating an action on the hydrogen ions existing in all the water in the body.

MRI equipment

This device consists of a tunnel with a magnet that revolves around the lying patient. It weighs tons and resembles a thick cylinder with a hole in the middle. A computer reconstitutes the images obtained and generates 3D quality definitions. Therefore, the patient must remain immobile in the equipment, which, in operation, can generate a lot of noise.

Where to do an MRI scan

Magnetic resonance imaging allows the visualization of some tissues not detected on the radiography, such as ligaments, central nervous system, muscles, heart and some tumors. It can also generate images of blood vessels with contrast. The resonance cuts in several planes: horizontal, vertical or transverse.

Resonance application areas

MRI is an examination that allows the visualization of numerous organs of the body, mainly the brain, spinal cord, spine, joints, urinary tract, kidneys, ovaries, uterus, prostate, sinuses, liver, abdomen, chest , arteries, etc.

Tumor diagnosis and monitoring

MRI is useful not only to assist in the diagnosis of tumors, but also to monitor their evolution, whether during or after treatment, preventing relapses.

How a resonance is performed

As stated above, the patient is lying on a kind of stretcher inside the machinery, which resembles a thick tube. Afterwards, the patient usually listens to music to minimize the loud noise from the equipment. The important thing here is that the patient is completely immobile.

A bell allows the patient to call the doctor from inside the equipment and suspend the procedure in case of problems. Monitored by a doctor and a radiology technician, the test can be performed, in some cases, with the help of medications that combat anxiety and relieve the feeling of claustrophobia. In case of contrast-enhanced MRI, the test should be done on an empty stomach and may last longer than a CT scan.

Precautions

Any metallic or magnetic object, such as keys, credit card or coins, must be deposited outside the examination room for the procedure to be performed.

Contraindications

Magnetic resonance imaging is not a dangerous test and can even be repeated several times. The only precaution is to avoid its performance in patients with a pacemaker or other type of heart valve that contains metal parts, in addition to brain clips and prostheses.

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