MRI of the spine: examination features, indications, results

• What is MRI of the spine?
• In what areas is MRI of the spine used?
• How should you prepare for research?
• What does the diagnostic equipment look like?
• What is the basis for the research?
• How is the research conducted?
• What should you expect during and after the procedure?
• Who reviews the research results and where can they be obtained?
• Benefits and risks of MRI of the spine
• Limitations of MRI of the spine

What is MRI of the spine?

Magnetic resonance imaging (MRI) is a non-invasive test that helps doctors diagnose and treat diseases.
MRI involves the use of powerful magnetic fields, high-frequency pulses and a computer system that allows you to obtain a detailed image of organs: soft tissues, bones and almost all structures inside the human body. The resulting images can be studied on a computer monitor, transmitted electronically, printed or copied to storage media. Ionizing (X-ray) radiation is not used in MRI.

Detailed images allow doctors to accurately assess the condition of various organs and systems and identify certain diseases that may be indistinguishable when using other examination methods, for example, X-ray, ultrasound or computed tomography.

With an MRI of the spine, the doctor can see the anatomical structure of the vertebrae that make up the spine, as well as the intervertebral discs, the spinal cord, and the spaces between the vertebrae where the nerve bundles pass.

In modern clinical practice, MRI is the most sensitive method for examining the spine.

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Where to get an MRI and how much does it cost?

If you are interested in where you can get an MRI of the spine, then contact a public or private clinic.

The table below will indicate the cities and medical institutions where you can get an MRI of the spine:

In public hospitals, MRI of the spinal column is cheaper, but private clinics have more modern equipment, qualified staff and better office conditions.

In what areas is MRI of the spine used?

MRI of the spine is used in the following cases:

• Assessment of the anatomical structure of the spine.
• Visualization of variants of the anatomical structure and pathologically altered tissue of the spine.
• Planning spinal surgeries such as decompression for nerve compression or spinal fusion.
• Monitoring changes in the condition of the spine, such as scarring or infection, after surgery.
• Control during the administration of steroid drugs for pain relief.
• Assessment of the condition of intervertebral discs and joints: degeneration, hernia, bulging, which are the most common causes of pain in the lower back and sciatica.
• Diagnosis of compression and inflammation of nerves.
• Determining the possible cause of back pain, for example, a compression fracture of the spine.
• Displays tumors or infectious processes that originate in or spread to the spine.

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Indications

An MRI of the lumbar region should be done only if certain symptoms are present, as well as if there is a referral from the attending physician. Among those conditions that MRI of the sacrolumbar region shows, it is worth noting the following:

• Osteochondrosis in the chronic or acute stage;
• Injuries of various nature;
• The likelihood of developing a tumor process;
• Metastasis to the lumbosacral region;
• Acute paroxysmal or aching continuous pain;
• Suspicion of an infectious process;
• Inflammation, impaired blood flow, etc.

How should you prepare for research?

The nurse may ask the patient to wear a hospital gown during the examination. If the patient's own clothing is loose, comfortable and does not have metal elements, then it is allowed to wear it. Recommendations regarding food and fluid intake before an MRI depend on the rules established by the diagnostic center. In general, the patient is allowed to maintain his usual daily routine and take food and medications in the prescribed order, unless the doctor says otherwise.

Because MRI may require contrast material to be injected into the bloodstream, the radiologist or nurse always asks the patient about any allergies, including to iodine or X-ray contrast materials, medications, food or environmental factors, and about the presence of bronchial asthma. However, MRIs typically use a contrast material such as gadolinium, which does not contain iodine and is less likely to cause any adverse or allergic reactions. In addition, the radiologist needs to know about any diseases that the patient suffers from, as well as about recent operations. Some medical conditions, such as severe kidney disease, preclude the use of contrast in MRI. If you have renal pathology, before an MRI examination, you must take a blood test, which will allow you to evaluate your kidney function.

A woman should always warn the radiologist about the possibility of pregnancy. MRI has been used to evaluate patients since the 1980s. twentieth century, and there are no reports of negative effects on the body of pregnant women or their children. However, during the study, the woman's body, along with the fetus, is placed inside a strong magnet. Therefore, MRI should be performed in pregnant women only in cases where the possible benefits of the study outweigh the possible risks. In addition, the administration of contrast material is contraindicated for pregnant women.

If you have claustrophobia (fear of closed spaces) or severe anxiety, the patient may ask the doctor for a mild sedative before the test.

Performing an MRI on a child, especially a young child, requires sedation, that is, the administration of sedatives, which ensures immobility during the procedure. The need for sedatives depends on the age of the child and the type of test ordered. Most diagnostic centers can provide sufficient sedation for the child while maintaining his consciousness. During the examination, a doctor or nurse should be with the radiologist who is responsible for the use of sedatives, which helps ensure the safety of the child. Before the procedure, the doctor must provide parents with detailed instructions on how to prepare the child for the administration of sedatives or anesthesia

It is advisable to leave all jewelry and other decorations at home or remove them before the examination. Metallic and electronic objects are not allowed in the treatment room as they may affect the operation of the magnet.

Such objects include:

• Jewelry, watches, credit cards and hearing aids that may be damaged during the examination.
• Pins, hair clips, metal lighters and similar metal objects that cause deformation of the MR image.
• Removable dentures.
• Pens, folding knives and glasses.
• Piercing.

In most cases, MRI is safe for patients who have metal implants in their bodies, with the exception of certain types. Persons with the following devices are prohibited from undergoing an MRI or being in the examination area, unless specifically authorized by a radiologist or technologist knowledgeable about the presence of the implant:

• Built-in pacemaker
• Cochlear implant
• Some types of clips that are used for cerebral aneurysms
• Some types of metal devices (stents) that are placed inside blood vessels

The presence of medical or electronic devices in the body must be reported to the radiologist, since these devices can interfere with the examination and carry a risk that depends on their type and the strength of the magnet. Examples of such devices include, but are not limited to:

• Artificial heart valves
• Installed ports for drug administration
• Installed electronic devices, including heart pacemaker
• Limb prostheses or metal joint prostheses
• Installed neurostimulator
• Metal plates, screws, pins, stents, or surgical staples.

In general, metal objects used in orthopedic surgery do not pose any risk during MRI. However, recent joint replacement may require a different study. If the doctor doubts the presence of metal objects in the patient's body, then diagnostic radiography may be performed.

X-ray examination before MRI is also required for all patients with metal objects in certain parts of the body or organs. It is important to notify the radiologist or technologist if there are any bullets, shrapnel, or other metal that may have entered the body as a result of the accident. The inks used in tattoos may contain iron and become hot during an MRI. However, this rarely poses a serious difficulty. Fillings and braces are usually not affected by the magnetic field, but these elements can distort images during MRI of the head and face, so they should always be reported to the radiologist.

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Contraindications for MRI

Absolute:

• applied vascular clips;
• electronic devices in the body (for example, ferromagnetic implants);
• presence of pacemakers.

Relative:

• body weight more than 130 kg;
• claustrophobia;
• metal fragments in the body;
• metal-ceramic dentures;
• severe forms of heart failure;
• conditions that do not allow the patient to remain immobile for a long time, etc.

What does the diagnostic equipment look like?

A standard MRI machine is a large cylindrical tube surrounded by a magnet. The patient sits on a movable examination table that slides inside a magnet.

Some CT scanners (called short-tunnel systems) are designed so that the magnet does not completely surround the patient's table. Some devices are open on the sides. Such tomographs are especially suitable for examining obese patients and people who suffer from a fear of closed spaces. Modern open MRI scanners make it possible to obtain very high-quality images for various examinations. However, if an open type machine uses an old magnet, the image quality may be reduced. Some studies cannot be performed on an open tomograph. For more information, consult a specialist.

The computer working system that processes the images is located in the room next to the scanner.

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What is the basis for the research?

Unlike traditional X-rays and computed tomography (CT), MRI does not require the use of ionizing radiation. Instead, the radio waves generated by the magnet change the direction of rotation in a powerful magnetic field of protons, which are the nuclei of hydrogen atoms.

In most MRI machines, a magnetic field is generated when an electric current passes through coils. Other wires located in the machine, and in some cases placed on the area of ​​the patient's body that needs to be examined, send and receive radio waves. This generates signals that are picked up by sensors.

The signals are processed by a computer program, resulting in a series of images, each showing a thin section of tissue. The resulting images can be examined from a variety of angles by a radiologist. Often, MRI is the best way to distinguish pathologically altered, diseased tissue from healthy tissue than other imaging techniques, such as radiography, CT or ultrasound.

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How is the research conducted?

MRI can be performed either on an outpatient basis or during the patient’s hospitalization. The radiologist's assistant places the patient on a moving table. The body position is secured using belts and special bolsters that help the patient lie still.

Devices containing wires that send and receive radio waves are placed around the area of ​​the body being examined.

Depending on the location of the symptoms, the doctor may prescribe an examination of only one part of the spine, for example, the cervical, thoracic or lumbar.

If it is necessary to use contrast material during the test, the nurse inserts a catheter into a vein in the arm. A bottle of saline solution may be connected to the catheter. The solution provides continuous flushing of the system, which prevents it from clogging before contrast material is injected.

After all preparations, the patient’s table moves inside the magnet, and the radiologist and nursing staff leave the treatment room for the period of the study.

After the examination is completed, the doctor asks the patient to wait until the analysis of the resulting images is completed, since an additional series of images may be required.

The intravenous catheter is removed.

A body MRI procedure typically consists of many sequences (series) of images, each taking several minutes.

The entire procedure usually takes about 45 minutes.

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Duration of MR imaging

To understand how long an MRI takes, you need to consider each stage of the procedure:

• The preparatory stage will take about 20 minutes. During this time, the patient changes clothes, removes unnecessary items, and lies down on the couch. If the study is carried out under anesthesia or with the use of painkillers (with severe pain), then the duration of this stage increases by another 15 minutes.
• At the second stage, an MRI scan is performed. Many patients are interested in how long this procedure takes. Depending on the type of examination and its volume, this will take 30–60 minutes. During this time, the patient must lie still in the tomograph.
• Then the doctor deciphers the results and advises the patient. The duration of the third stage is from 30 minutes to 2 hours. The speed of data processing depends on the severity of the disease.

Reference. For MRI scans with contrast, an additional 15 minutes are added to the total time to administer the solution.

And patients are also interested in how often an MRI of the spine can be done. According to doctors, this study is safe, so it can be repeated after a short period of time.

What should you expect during and after the study?

In most cases, an MRI is completely painless. However, some patients experience discomfort due to the need to lie still during the test. Other patients may experience an attack of claustrophobia (fear of closed spaces). This is why doctors offer sedatives for anxious patients, but in reality only 1 in 20 people need them.

During the study, a local increase in the temperature of the body area being examined is possible, and this is normal. However, if this phenomenon greatly bothers the patient, it is important to inform the doctor about it. It is extremely important that the patient lie absolutely still while the images are being taken (from several seconds to several minutes at a time). During some tests, the doctor asks the patient to hold their breath. The tapping or clicking sounds that the magnet makes as it produces high-frequency pulses help you know when image capture has begun. You can relax a little between series of shots, but you should still try to maintain your body position, without moving if possible.

Typically, the patient is alone in the treatment room during the examination. However, the radiologist can see, hear and talk to the patient at all times via a two-way communication system. Staff at many diagnostic centers allow relatives or friends of the patient to remain in the room until the test begins. However, they then need to go out to avoid exposure to the magnetic field.

The patient may be given headphones or earplugs to help suppress the loud knocking and humming of the scanner while images are taken. The patient has the right to ask for headphones himself. Children must be provided with headphones or earplugs of the appropriate size. The MRI scanner is air conditioned and well lit. Some centers play soft music during the examination.

When a contrast material is injected, there is normally a feeling of coolness or a rush of blood that lasts a couple of minutes. The patient experiences some discomfort when inserting and removing an intravenous catheter, which can leave hemorrhage under the skin. It is extremely rare that irritation occurs on the skin at the site of needle insertion. Some patients experience a metallic taste in their mouth after receiving contrast material.

If the procedure was not accompanied by the use of sedatives, then a recovery period after it is not required. A return to normal activities and normal nutrition is possible immediately after the study. Some patients experience side effects when contrast is administered, such as nausea and local pain. It is extremely rare for an allergic reaction to the contrast material to occur, resulting in hives, itchy eyes, or other allergy symptoms. If you experience symptoms of an allergic reaction, you should inform your doctor. A radiologist or nurse will immediately provide the necessary assistance.

Manufacturers of contrast materials do not recommend breastfeeding for 24-48 hours after intravenous administration of contrast to the mother. However, experts from the American College of Radiology and the European Society of Urogenital Radiology report that research suggests that it is safe to continue breastfeeding after the use of intravenous contrast materials.

The American College of Radiology guidelines on the use of contrast materials state: “A review of the published literature indicates that oral administration by infants of small amounts of gadolinium-based contrast material that is excreted in breast milk does not cause any toxic effects. Therefore, we believe that after the introduction of such materials, continued breastfeeding is safe for both mother and baby. If the mother is concerned about the development of any unwanted effects, she should be given the opportunity to either continue breastfeeding after administration of gadolinium contrast or temporarily discontinue it. If the mother decides to stop breastfeeding for 24 hours after administration of the drug, then active expression of milk from both breasts is recommended during this period. Alternatively, a breast pump may be used before an examination using a contrast agent, which allows for enough milk to be fed to the baby for 24 hours after the procedure.”

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Preparation and execution

Patients who have been prescribed an MRI are interested in how the procedure goes. To get accurate results, you need to properly prepare for the examination. No special preparation is needed; a person can continue to follow their usual regimen, not change their diet, and continue to take medications. Only about the last point you need to warn your doctor.

Doctors advise not to eat before an MRI, namely 3 hours before the examination. If you plan to remain in your clothing during the procedure, make sure that it is loose and does not have metal parts. In addition, you need to remove all metal jewelry and removable dentures from your body.

Attention. Before an MRI with contrast, it is recommended to have blood tests to make sure you are not allergic to the chemical compound used. This is important because some patients experience a rash, mild headache, and dizziness after contrast administration. However, adverse reactions occur rarely and disappear quickly.

If the patient has claustrophobia, he should warn the doctor about this. People with unstable mental health, as well as children, are asked to take medications with a sedative effect before being examined in a closed-type tomograph.

During an MRI, you need to lie still to ensure clear images.

Before the MRI scan, the diagnostician tells the patient how the procedure is done and how long it takes. The patient enters the office, takes off unnecessary items, puts on hospital clothes if necessary, and lies down on a pull-out couch. Depending on the area being examined, belts are fixed on it and rollers are placed. Then the diagnostician goes into the next room and turns on the tomograph. The table slides into the machine, which begins to make loud noises. To relax, the patient can wear earplugs or headphones with music. During the procedure, the patient can communicate with the doctor through a special microphone.

Important. During the examination, while the table is inside the device, the patient is prohibited from moving. This condition must be met to get clear images.

MRI with contrast differs from standard MRI only in that before the procedure the patient is given an infusion of a dye solution.

In most cases, the MRI scan goes without problems, and there are no negative reactions after its completion.

The video below will show how an MRI occurs.

Who reviews the research results and where can they be obtained?

The images are analyzed by a radiologist: a doctor who specializes in performing radiological tests and interpreting their results. After examining the images, the radiologist draws up and signs a report, which is sent to the attending physician. In some cases, the report can be collected from the radiologist himself.

A follow-up examination is often required, the exact reason for which will be explained to the patient by the attending physician. In some cases, additional examination is carried out when doubtful results are obtained that require clarification during repeated images or the use of special imaging techniques. Dynamic observation allows timely identification of any pathological abnormalities that arise over time. In some situations, repeated examination allows us to talk about the effectiveness of treatment or stabilization of tissue condition over time.

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Why is an MRI prescribed?

In addition to the fact that MTP is prescribed to obtain detailed information about the condition of bones and tissues, bypassing surgical intervention, this study is often used to monitor various neoplasms.

For example, when a cyst or other growth, the nature of which is unknown, is discovered inside bone tissue or the spinal cord, the attending physician first prescribes regular examinations with a certain frequency in order to determine the state of the formation over time: is it growing or not, and at what speed. This allows you to understand the etiology of the growth and determine the correct tactics of medical behavior.

Benefits and risks of the study

Advantages:

• MRI is a non-invasive imaging technique in which the patient's body is not exposed to ionizing radiation.
• MRI, compared to other imaging methods, allows you to obtain clearer and more detailed images of the spine. This property makes MRI an invaluable tool for early diagnosis and assessment of the condition of many spinal diseases, including tumors.
• MRI has a proven diagnostic value for a number of diseases, including congenital pathology of the spine, chronic diseases of the spinal cord, for example, multiple sclerosis, bone anomalies such as fractures, etc., diseases of the intervertebral discs (for example, hernias), vascular anomalies, infections and tumors.
• MRI can detect pathological lesions hidden by bone formations and therefore invisible to other imaging methods.
• The contrast material used in MRI is much less likely to cause allergic reactions than the iodine-based contrast used in traditional x-rays and CT scans.
• MRI can detect diseases, injuries, and abnormalities in the spinal cord that are not visible with other imaging techniques.
• MRI is extremely useful in evaluating patients with spinal injuries, especially in diagnosing acute spinal cord compression when physical examination reveals paralysis or muscle weakness.
• MRI can detect minute changes in the spine that may indicate an infection or tumor. The procedure is much more sensitive when examining tumors, abscesses and other soft tissue formations of the spinal cord compared to CT.

Risks:

• If appropriate safety guidelines are followed, MRI carries virtually no risks for the average patient.
• When using sedatives, there is a risk of overdose. This is why the radiologist assistant carefully monitors the patient's vital signs.
• Despite the fact that the powerful magnet in the scanner itself is harmless, problems during MRI can arise if there are devices implanted into the patient's body that contain metals.
• When contrast material is injected, there is a very small risk of developing an allergic reaction. Such reactions are usually very mild and go away quickly when appropriate medications are prescribed. If allergy symptoms occur, a radiologist or nurse will immediately provide the necessary assistance.
• One recently described, but extremely rare, complication of MRI is nephrogenic systemic fibrosis, which develops when large doses of gadolinium-based contrast material are administered to patients with impaired renal function.

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The most important

When the first problems with the spine appear, you should seek medical help. Such a highly informative study as magnetic resonance imaging will detect even the slightest pathological changes in the bone structure, as well as the surrounding tissues. To obtain reliable research results, you need to prepare for it and behave correctly during it. Ask your doctor in advance about possible contraindications to avoid negative reactions. MRI has a high advantage over x-rays in identifying spinal pathologies. However, the decision to choose the appropriate procedure is made by a specialist, taking into account the characteristics of the course of the disease and the general condition of the patient.