MRI: what is it and how is this test performed?

Throughout the history of science, the human body and what it contains within it have aroused the interest of all health researchers. Fortunately, thanks to advances in science, it is no longer necessary to carry out invasive tests that risk the health of the patient.

In 1971, Dr. Raymond Damadian and his team created the first magnetic resonance imaging, a totally painless test that allows the observation of the interior of our body using highly detailed images.

• Related article: "Electroencephalogram (EEG): what is it and how is it used?"

What is a nuclear magnetic resonance?

Magnetic resonance imaging (MRI) is a diagnostic test that emits images of the inside of our body. Through this test, clinical staff can detect any abnormality that is not perceptible to the naked eye or with other tests such as radiography.

The main feature that distinguishes this test compared to X-rays or computerized axial tomography (CT) is that the MRI does not use ionizing radiation or X-rays. Rather, this technique employs a series of

radio waves passing through the patient's body, which is exposed to a strong magnetic field.

Another advantage of nuclear magnetic resonance is that by using it, high-detail images can be obtained from any point and from any perspective of the body; even being obtained in two or three dimensions.

To obtain these images the person is introduced into a large machine visage at a giant-sized UVA machine. The person must remain lying inside it for a variable time ranging from 30 to 60 minutes. However, some centers have open machines adapted for people with fear of being locked up.

This MRI image is called a "slice." Large number of images can be obtained in a single test, which can be stored digitally or printed on paper.

Finally, there are different types of MRI tests, depending on the area to be examined.

• MRI of the head
• Chest MRI
• Cervical MRI
• MRI of the abdomen
• Pelvic MRI
• MRI of the heart
• Lumbar MRI
• MRI angiography
• MRI Venography

When should an MRI be done?

Conducting an MRI, accompanied by other examinations, tests and evaluations, are of great help for healthcare professionals when making any type of diagnosis.

When medical personnel suspect or notice any sign of disease, they usually request an MRI scan, usually in a specific area or place on the body.

Typically, the most common reasons for requesting this test are the following.

1. MRI of the head

To detect tumor formations, aneurysms, strokes, heart attacks, or brain injuries. Likewise, they are also used to evaluate ocular or auditory system disorders.

2. MRI of the abdomen or pelvis

It serves to evaluate organs such as the kidneys, liver, uterus, or ovaries and the prostate.

3. Bone MRI

Through this technique, problems such as fractures, arthritis, hernias, etc. can be identified.

4. Chest MRI

Especially useful for examine the heart anatomy and assess possible damage or abnormalities in the arteries. In addition, it also reveals tumors in breast and lung cancer.

5. MRI Venography

This type of MRI facilitates the observation of thrombi, infarcts, aneurysms or malformations in the blood vessels.

How should the patient prepare?

There are a number of issues that the patient should consider before undergoing this test. Likewise, it is the obligation of healthcare personnel to inform the person about how this procedure is and what obligations or points to take into account the person must have before performing an MRI magnetic.

1. Necessary documentation

Healthcare personnel should give the patient an informed consent in which it is explained in detail what the test consists of and what possible risks it entails. The person must sign this consent and take it with them on the day of the test.

2. Feeding

Depending on the organ to be examined, it will be necessary for the person not to eat any type of food, do not drink any liquids for a few hours before the test.

3. Company

Magnetic resonance imaging it is a totally painless and non-invasive test so it will not be necessary for the person to be accompanied. However, in cases where the person experiences fear or anxiety, the company of someone they know can be of great help.

4. Clothing

During the test the person you should wear only the hospital gown, being necessary to undress before performing the test. Likewise, it is mandatory to remove any type of metallic object such as earrings, bracelets, hair accessories, etc.

Duration of the test and admission

The MRI test usually takes about 30 to 60 minutes. Since any type of anesthesia or intervention is not necessary for its realization, it is always performed on an outpatient basis, so the admission of the person is not necessary.

Despite being a practically innocuous technique, there are a series of contradictions:

• Cases of allergy to contrasts used in MRIs.
• Women with intrauterine devices (IUD).
• People who have some metallic component inside their body such as screws, pacemakers, shrapnel, etc.
• Patients with claustrophobia.
• People suffering from obesity.
• Cases of severe kidney or liver failure
• Patients undergoing surgery on a blood vessel.
• Unstable or clinically serious patients who may need some type of resuscitation maneuver
• Lactating women should not breastfeed the baby after 24-48h after the test., in cases where some type of contrast has been administered.

In all these cases, patients must inform the hospital staff in order to adapt the test to their personal needs, without the need to run any type of risk.

How is the MRI performed?

As mentioned above, the MRI machine has an elongated cubic shape within which a table is placed. This stretcher slides into the device and the patient must lie on his back. and absolutely motionless throughout the test.

Depending on the type of test, intravenous inoculation of a contrast substance will be necessary to highlight the organs examined. This substance is known as gadolinium and its main advantage is that as it does not contain iodine, it is not likely to cause any side effects.

In cases where it is necessary (anxiety or fear) the patient can be given some type of relaxing medication to prevent movement during the test. In addition. Your arms, head, or chest may also be restrained using straps.

Once the test has started the person may perceive an intense sound of ventilation and the tapping of the test itself. Headphones can be offered to the person to lessen discomfort.

Throughout the procedure, imaging technicians will monitor the patient to give instructions, as well as to attend them in cases in which there is any incidence.