home Drugs The diagnostic procedure is magnetic resonance imaging. How long does an MRI examination of different organs take?

The diagnostic procedure is magnetic resonance imaging. How long does an MRI examination of different organs take?

What are “artifacts” on MRI images?

Artifacts (from the Latin artefactum) are errors made by humans during the research process. Artifacts significantly degrade image quality. There is a wide group of physiological (in other words, related to human behavior) artifacts: motor, respiratory, artifacts from swallowing, blinking, random uncontrolled movements (tremor, hypertonicity). All artifacts associated with the human factor can be easily overcome if the person is completely relaxed during the study, breathes smoothly and freely, without deep swallowing movements and frequent blinking. However, in medical practice there are often cases lung use anesthesia

At what age can children have an MRI?

Magnetic resonance imaging does not have age restrictions, so it can be performed on children from birth. But due to the fact that during the MRI procedure it is necessary to remain still, the examination of young children is carried out under anesthesia (superficial anesthesia). In our center, examinations are not carried out under anesthesia, so we examine children exclusively from the age of seven.

What are the contraindications to MRI?

All contraindications to MRI can be divided into absolute and relative.
Absolute contraindications to MRI are: following features patient: the presence of a pacemaker (heart pacemaker) and other implantable electronic devices, the presence of ferrimagnetic (iron-containing) and electric stapes prostheses (after reconstructive operations on the middle ear), hemostatic clips after operations on cerebral vessels, abdominal cavity or light, metal fragments in the orbital area, large fragments, shot or bullets near the neurovascular bundles and vital important organs, as well as pregnancy up to three months.
Relative contraindications include: claustrophobia (fear of closed spaces), the presence of massive non-ferrimagnetic metal structures and prostheses in the patient’s body, the presence of an IUD (intrauterine device). In addition, all patients with magnetically compatible (non-ferrimagnetic) metal structures can be examined only a month after the surgical intervention.

Is it necessary to have a doctor's referral to get an MRI?

A doctor's referral is an optional condition for visiting the MRI center. Your concern for your health, consent to the examination, and the absence of contraindications for MRI are important to us.

I get headaches often. What area should an MRI be done?

Any person is familiar headache, but if it is repeated suspiciously often, of course, this cannot be ignored. We recommend that a patient with severe headaches undergo an MRI of the brain and its vessels. In some cases, this may not be enough, because the cause of headaches is not always associated with brain pathology. Headaches may be a consequence cervical osteochondrosis, so our experts additionally advise you to undergo an MRI cervical region spine and neck vessels.

How long does an MRI test take?

Average duration One study in our center takes from 10 to 20 minutes, however, it all depends on the changes detected: sometimes, to clarify the disease, the radiologist may expand the study protocol and resort to the use of contrast enhancement. In such cases, the research time increases.

Recently, MRI remains one of the most informative and safe methods diagnostics The examination is carried out using a tomograph, which is a large magnet.Despite the fact that the tomograph does not have any harmful radiation or effects on the body, the information content and reliability of such an examination is very high. However, like any procedure, it has its contraindications. Failure to follow safety rules can have unpleasant consequences.

The tomograph influences the human body with electromagnetic radiation, which allows you to display an image on the screen. Various fabrics transmit these waves differently. This electromagnetic response is highly accurate. You can use it to determine various diseases: from fractures to malignant tumors.

As a rule, there are no negative consequences of MRI if contraindications are taken into account and safety precautions are observed. The peculiarity of this examination method is non-invasive and painless. This significantly reduces the likelihood of unpleasant consequences.

Depending on the part of the body being examined, the MRI procedure has several types:

MRI of the head and neck. In this case, the variety includes examination of the hemispheres, as well as the vessels of the brain, cervical spine and. The examination can also help with damage to the optic or auditory nerve.
MRI chest. The MRI procedure allows you to identify various pathologies of the chest organs: heart, lungs, and also. Quite often, MRI is performed to determine oncology, damage to the heart valves or arteries.
. This type of MRI is also called magnetic resonance angiography. It allows you to determine the presence of blood clots, plaques, vascular ruptures, as well as various congenital anomalies.
. The MRI procedure allows you to examine not only the spine itself, but also the tissues located nearby. This will help identify fractures, slipped discs, and tissue infections.
MRI of bones and joints. The procedure is performed when various infectious, inflammatory diseases of bone or joint tissue are suspected, or when examining the consequences of injuries.
And . The examination includes all abdominal organs:, etc. You can also examine reproductive system(uterus, ovaries in women, prostate gland in men).

There is also a full body MRI. However, this is a rather expensive procedure. It is used when it is impossible to make a diagnosis, as well as when searching malignant tumor and determining the spread of metastases.

Preparation and procedure

The MRI procedure lasts a total of 30 minutes. No special preparation is required, but before the procedure the patient must fill out a questionnaire indicating all possible allergic reactions, presence in the body metal parts or parts (prostheses, shunts, electrical stimulators).

If you use a contrast agent, it is recommended that you refrain from eating before the procedure, as you may feel nauseous. Women are advised not to use cosmetics before the procedure, as they may contain metal particles. Instructions regarding the intake of food or liquid are given only during examination of the abdominal organs.

Also subject to availability excess weight The patient is being weighed. The tomograph is designed for a certain weight. If it exceeds the permissible limits, an open tomograph is used.

The procedure itself takes place in several stages:

First the patient enters separate room, changes into the clothes provided. You must remove all jewelry and clothing that contain metal parts. You should also leave your keys, piercings, dentures if you have one, belts, watches, etc.
The patient enters the MRI room and lies down on a sliding table that slides inside the tunnel tomograph. The basic rule for performing an MRI is that the patient must lie still during the entire operation of the tomograph. If small children are undergoing the examination, the procedure is carried out under anesthesia in the presence of an anesthesiologist.
There should be no discomfort during the procedure. But the tomograph is quite noisy, so prolonged hum often leads to headaches. The patient may be given headphones.
If discomfort occurs, the patient can press the button to contact the doctor and report his condition. In some cases, patients begin to experience an attack of claustrophobia during the examination. Unpleasant sensations in a confined space can occur even if the person has not previously suffered from claustrophobia.

After the procedure is completed, the patient can take the result within an hour or wait for a consultation with a doctor who will decipher the conclusion. You will receive both a photograph and a written report.

Complications and dangers of MRI

MRI is a fairly safe procedure. There is not a single scientific fact proving the harmful effects of electromagnetic waves on the human body. Many people are afraid of this procedure, not understanding its essence. MRI is not X-ray examination, so there is no harmful radiation in this case.

The following complications may occur during and after the procedure:

An attack of claustrophobia. It's more likely unpleasant effect, which appears directly during the examination. IN severe cases the patient is offered a procedure using an open tomograph, but the information content in this case will be reduced. If the attack of claustrophobia is not severe, to alleviate the patient’s condition, they can turn on a fan to provide fresh air, remove the pillow from under the head, or roll over on their stomach.
Tissue damage. If there are metal parts in the body, under the influence of the tomograph they will begin to attract, tearing soft fabrics. The likelihood of such a complication is very low. As a rule, people are aware of the presence of metal objects in the body and report it. Before the examination begins, the clinic employee conducts an additional test using a metal detector.
Negative effects on the fetus. Pregnant women can have an MRI without the use of a contrast agent, but the effects of imaging on the fetus in the first trimester are not clear, so it is recommended to refrain from the examination. But if a woman undergoes an MRI for early stages does not yet know about pregnancy, this is not an indication for a medical abortion.
Allergic reaction. An allergy can only occur to the product that is used during the examination. As a rule, private clinics conduct an allergy test in advance.

The procedure does not have any cumulative effect. It can be done as often as the patient requires. The risk of complications in this case is small, but MRI is never prescribed for prevention. It is advisable to obtain a doctor’s referral and clarify the condition of the body so that unforeseen complications do not arise.

Contraindications for MRI

Despite the safety of magnetic resonance imaging, this procedure has a number of contraindications. In order to identify the presence of certain characteristics of the body, a survey is carried out. It helps determine how safe the procedure will be. It is very important that the patient answers all questions honestly.

If an MRI procedure is prescribed by the attending physician, he warns about possible consequences and assesses the condition of the patient’s body. Preparations are also announced in advance.

The list of contraindications for MRI includes:

The presence of metal objects in the body and a pacemaker. Magnetic waves disrupt the functioning of the stimulator and attract any metal objects with great force. This could result in serious injury.
Availability of insulin pumps. This medical device for administering insulin may also contain metal parts. His work is disrupted under the influence of the tomograph.
Pain syndrome. In case of severe pain, MRI is not performed because the person cannot long time be in a motionless state. Before starting the procedure, it is necessary to relieve pain or perform another diagnostic procedure.
Presence of mental illness. Patients with mental illness it is impossible to explain the need to remain motionless. In this case, an MRI can only be performed under anesthesia.
Tremor. Tremor is accompanied by involuntary movements, which can make the procedure difficult.
First trimester of pregnancy. During the period of fetal formation, it is not advisable to carry out any procedures or take medications. If a woman requires an MRI, it is recommended to reschedule it until the beginning of the 2nd trimester.
Epilepsy. The operation of the tomograph may provoke epileptic seizure, therefore this disease is a contraindication to MRI.

Some contraindications have already become obsolete. For example, for a long time it was believed that MRI should not be performed if there are tattoos on the body. However, modern tattoo parlors do not use ink containing metal, so there are no consequences during MRI.

Everything you need to know about contrast media

There are several varieties contrast agent. MRI uses contrast that does not contain iodine, so the likelihood allergic reaction minimal. Most often carried out intravenous administration contrast agent. The need for its use is determined by the attending physician.

In most cases, a gadolinium contrast agent is used.

The difference between MRI with and without contrast lies only in more detailed information and determination of the boundaries of tumors.

As a rule, contrast is completely safe and does not lead to any complications. However, some side effects may occur:

Allergy. An allergic reaction to gadolinium is rare. It manifests itself in the form of skin rashes, itching, and redness of the skin at the injection site.
Demotion. Gadolinium may slightly reduce arterial pressure, but to serious consequences it doesn't lead.
Fluid retention in the body. This by-effect occurs only in the presence of kidney disease. Swelling occurs and the drug is slowly eliminated, which can lead to intoxication.

Modern medicine uses MRI of the spine as a highly informative procedure for examining patients with pathologies of bone and soft tissues of the body or suspected of their presence. The method of layer-by-layer imaging of the structure of examined objects is used not only to diagnose existing diseases, but also to determine the stage of their formation and development. In addition to diagnostic accuracy, MRI eliminates harm to the body of the examined patients.

What is MRI of the spine?

The magnetic resonance imaging method is based on the interaction of strong magnetic field, artificially created by a tomograph apparatus, and hydrogen atomic nuclei found in the human body. Speed of response to external stimulus depends on the saturation of the body with hydrogen atoms and the energy they release. In addition to a powerful magnet, the tomograph includes a gradient coil, which determines the location of the signal in space and allows an image to be taken.

The accuracy of diagnosing diseases using MRI depends on the competence of the doctor. Interpretation of the obtained images of the spine makes it possible not only to see the surface of the bone tissue of the spine, but also to analyze the condition of the spinal cord and determine its thickness in all areas. If a tumor is suspected in the brain or spinal cord, the MRI procedure involves intravenous administration of a contrast agent. This technique facilitates structural analysis of the diagnosed vertebral zone.

Indications for MRI

The doctor may prescribe an MRI for patients with diseases of the spine and joints or for those who have previously undergone MRI diagnostics in order to track the results of the treatment. In addition, tomography is indicated if the following pathologies are suspected:

spinal cord damage (ischemic, tumor, inflammatory);
osteochondrosis of the cervical spine;
osteoporosis;
intervertebral hernia;
vascular obstruction;
displacement of the vertebrae of the lumbar spine (spondylolisthesis).

The need for magnetic resonance imaging arises when there are complaints of severe headaches, numbness in the extremities, or after injury. Even if pain does not appear immediately after an injury or accident, it is recommended to undergo an MRI diagnostic procedure to investigate possible pathogenic changes in the spine, the symptoms of which may appear several years later.

Advantages

Magnetic resonance imaging is a breakthrough in the discovery of methods for studying the structure of the human skeleton and organs. The invention of the tomograph provided world medicine with the following opportunities:

get clear images spinal column in all projections;
detect the presence of a tumor at an early stage;
identify pathogenic changes in bone tissue;
give timely recommendations to prevent the development of spinal pathologies;
conduct examinations of the spine and joints without the use of ionization radiation.

Using the magnetic resonance method, it became possible to visualize the condition of the vertebrae and intervertebral discs. The difference between MRI and other diagnostic methods is the ability to detect prolapse ( First stage formation intervertebral hernia), which simplifies the process of preventing the transition of the disease to chronic form. Before the discovery of MRI, such problems were identified at the stage obvious manifestation diseases.

The price of the MRI procedure is completely justified due to the fact that after diagnosis using magnetic resonance imaging there is no need to conduct other types of examination. High information content of the obtained results helps to avoid expenses for additional methods. According to reviews from patients examined using MRI, diagnostic techniques that are cheaper do not always justify the cost savings obtained.

How often can you do it

Negative impact MRI of the spine was not detected during experimental studies and during the entire practice of using this type of diagnosis. This procedure is harmless even for infant. The only inconvenience may be the need to maintain a motionless position during the entire resonance tomography session. MRI, if necessary, is allowed at least daily. There are no restrictions on the time and frequency of diagnosis on the part of doctors.

Preparation

Carrying out a magnetic resonance examination does not require any special preparation. Clothing should be loose, without metal buttons or fasteners. Before the examination, you must remove all jewelry and remove items that may contain metal particles from your pockets. Dentures, if they are removable, will also have to be left outside the procedure room. Patients with psychopathological symptoms and young children may be offered lungs before MRI. medications sedative effect.

Preparation for an MRI of the lumbosacral spine, if it is carried out with the introduction of contrast, additionally involves taking a blood test to prevent the possibility of an allergic reaction to the injected drugs. Due to the fact that the contrast is based on the metal gadolinium, the possibility of adverse reactions is minimized, but not excluded.

How they do it

The procedure for magnetic resonance imaging of the spine takes place in a specially equipped room. A standard tomograph is a large cylindrical tube with a movable table inside. Before diagnostic study Undressing is required only if the patient's clothing contains permanent metal objects or is too tight to the body.

Immediately before the diagnostic procedure, the patient takes off his shoes and lies down on the table. The limbs are secured using special straps to ensure immobility during the MRI procedure. Depending on the part of the spine being diagnosed, the movable surface moves to a certain level inside the pipe. The doctor always remains in touch with the patient being examined through a microphone installed in the device. During the session, discomfort can only arise due to sharp sounds, the purpose of which is to cause the necessary resonance.

How long does it take to do an MRI?

Tomography of the spine without the introduction of a contrast agent lasts from 20 to 45 minutes. The need to administer the drug increases the duration of the examination, and it ranges from 30 minutes to 1 hour. The results of the procedure in the form of images and disks recorded in DICOM format are delivered within half an hour. The doctor who diagnosed the spine provides his diagnostic report in printed form, certified by signature and stamp.

What does an MRI show?

The images obtained after an MRI of the back can be deciphered by the attending doctor who gave the referral for examination. When approving the final diagnosis, the conclusion of the specialist who performed the tomography procedure and printed images of the spine is taken into account. A detailed analysis of photographs can show:

condition of the bone tissue of the vertebral discs;
the presence of inflammatory processes in soft tissues;
congenital or acquired anomalies in the structure of the vertebrae;
tightness nerve endings;
spinal cord damage.

When contacting diagnostic center Without a referral, it is possible to order, for a fee, the service of interpreting the images obtained during a spinal examination. The consultation center specialists will provide qualified assistance, if you provide them with MRI diagnostic results on removable media and in printed image format. Self-diagnosis is highly undesirable.

Contraindications

MRI is harmless to the spine, but given the use of strong magnetic fields during the procedure, there are several contraindications for diagnostics using this method. These include:

the presence of metal implants or prostheses;
the presence of tattoos on the patient’s body;
overweight (weight more than 120 kg);
panic fear of closed spaces.

Women should be informed before undergoing a spinal diagnostic procedure. possible pregnancy due to the fact that the influence of the magnetic resonance field on fetal development has not been fully studied. During lactation, it is better to consult a doctor about the possibility of diagnosing in this way. Magnetic resonance imaging of the spine is not performed if urgent diagnosis is necessary and in case of acute pain syndrome. An allergy may become an obstacle to performing a tomography with the introduction of a contrast agent.

What is the price

Patients suffering from back pain of unknown etiology often turn to doctors to find out where to get an MRI of the lumbosacral spine. In Moscow, MRI procedures can be performed cheaply and with high quality in specialized clinics. The cost of an MRI of the spine ranges from 1,800 to 17,000 rubles. The price of services depends on the area of the back and the need to administer contrast agents, and sometimes on the time of day the diagnosis is performed.

When turning to the services of specialists who offer a cheaper option for diagnosing the spine using MRI, you should check for a doctor’s certificate, an institution’s license to provide medical services and a valid license for equipment used for examinations. Often low prices hide the lack of quality, which is unacceptable in matters of health.

Video: how to do an MRI of the spine

Magnetic resonance imaging is a diagnostic method for studying the human body using nuclear magnetic resonance.

The principle of the study is to influence tissues and organs with electromagnetic waves that are in a controlled constant magnetic field of high intensity. The caused excitation of the nuclei of hydrogen atoms gives a registered electromagnetic response, which is used as a result.

MRI is one of the most modern and accurate diagnostic examinations. It was developed in 1973 by P. Lauterburg. It appeared in the USSR in 1984 under the name NMR (nuclear magnetic resonance). Since 1986, the name was changed to the modern one.

When performing MRI, a magnetic field strength of 1.5 Tesla is used. Most equipment operates at this value standard. The thickness of the resulting sections from 1 to 5 mm allows you to see small details of the tissues and organs being examined with a high-quality image.

The study makes it possible to conduct detailed diagnostics of all tissues of the body. It is especially convenient to use a 3D image to obtain accurate information.

Note:One of the main advantages of MRI is its complete harmlessness and the absence of radiation exposure. This allows the study to be carried out on patients who have contraindications to X-ray diagnostic methods.

Modern modifications of MRI include:

virtual endoscopy, allowing you to get a three-dimensional image;
MRI diffusion, recording the movement of intracellular fluid;
diffusion-weighted tomography, which determines the movement of radiolabeled protons (used in oncology);
MR perfusion– diagnostics of blood flow (used for strokes, circulatory disorders, ischemic processes in organs);
MR spectroscopy– a combined method that allows you to detect biochemical changes in fluids and tissues;
MR angiography, which makes it possible to obtain images of sections of blood vessels.

All received information is recorded on the media.

Magnetic resonance imaging is used to diagnose diseases of most organs and systems. The study can be carried out comprehensively, simultaneously capturing the entire body. MRI has a number of advantages compared to CT (computed tomography), scintigraphy, arthrography, ultrasound, classical X-ray, and angiography. We will talk about these advantages in more detail when describing the MRI techniques used.

Most often, an isolated version of examining individual parts of the body is used. Each of these methods has its own indications.

Indications for MRI of the head area

The method allows you to determine the pathology of the main vessels of the brain (constrictions, aneurysms, congenital anomalies), traumatic changes in the structures of the bones of the skull and brain, as well as complications (cystic formations, hematomas, accumulation of fluid in the brain tissue).

As a result of the study, neoplastic processes in the brain as a whole and in its individual structures (cerebellum, pituitary gland, brainstem), inflammatory changes in the brain (meningitis, encephalitis, abscesses), and brain atrophy in various diseases are determined.

The study makes it possible to find the pathology of anatomical formations of the middle and inner ear, diseases of the paranasal sinuses, orbits and eyeballs, jaw joints.

Indications for MRI of the spinal cord

MRI for diseases of the spinal cord allows you to detect anatomical defects in multiple sclerosis and encephalomyelitis, cystic and tumor processes;

The study successfully determines the number and localization of intervertebral hernias, inflammatory changes in the spinal cord, vertebral joints (spondylitis and spondyloarthrosis), tumors, traumatic injuries, vascular changes, developmental anomalies. The narrowing is clearly visible spinal canal, coccyx cysts;

Indications for MRI of joints

Note:The main advantage of MRI of joints in comparison with CT (computed tomography) is the ability to clearly determine the structure of joints and soft tissues. Ligaments, menisci and synovial membranes are visualized.

Magnetic tomography has made it possible to develop diagnostics early stages necrotic changes in the heads femur, partially replaced contrast arthrography techniques. It has also replaced osteocytigraphy in the detection of metastases.

The study is used for inflammation of the joints (arthritis), injuries of joint-muscular formations (tears of the menisci, lesions elbow joints etc.), purulent-necrotic joint processes, osteomyelitis, fractures.

Painful processes in muscle pathologies, problems of ligaments and tendons are well visualized;

Indications for MRI of the mammary glands

This type of examination is becoming increasingly common, especially in determining pathologies of a tumor nature.

note: unlike mammography, it does not expose the woman’s body to radiation.

Allows you to differentiate the benign and malignant nature of neoplasms. Also visualizes mastitis, abscesses and other types of purulent inflammatory pathology mammary glands. The study is recommended to be carried out between 6 and 17 days of the female cycle;

Abdominal MRI

Note:the study allows you to identify subtle anatomical details that are inaccessible to ultrasound.

Indications for this procedure are:

suspicions of tumor processes liver and bile ducts, cirrhosis, cystic formations;
necessity dynamic observation for the treatment of tumor processes;
diagnosis of enlarged liver, consequences of injuries, cholelithiasis, pathological processes pancreas;

Note:MRI has the ability to examine the small and large intestines without standard x-ray techniques (irrigoscopy, colonoscopy) in weakened patients, and greatly simplifies patient preparation.

Before the procedure, a cleansing enema is performed, then 150 ml of liquid is injected into the intestine through a thin probe to facilitate visualization. Used for diagnosing inflammatory and tumor processes of the intestine;

Indications for MRI of the kidneys and adrenal glands

MRI of the kidneys and adrenal glands is indicated to determine the size and volume of neoplasms, stones, and in diagnosing abnormalities in the structure and location of the kidneys and the urinary system as a whole.

Note:MRI of the kidneys is especially indicated for patients who cannot undergo urography using contrast agents;

MRI of the pelvic organs

It is used in women for the diagnosis of malformations and inflammation of the uterus and appendages, cystic formations female genital organs, tumor processes and metastases, if endometriosis is suspected.

Note:MRI allows you to visualize details that ultrasound cannot detect.

In men, a diagnosis is made of anomalies in the development of the genital organs, hyperplastic processes of the prostate, cysts, inflammatory processes and tumors of the prostate gland, testicles, and bladder.

Contraindications to MRI are divided into absolute and relative:

absolute– the presence of metal prostheses and vascular clips in the human body, a functioning pacemaker, an auditory implant;
relative– severe fear of enclosed spaces mental pathology in the stage of excitement, severe pain that does not allow you to lie still, sometimes in the first trimester of pregnancy (in this case, the study can be postponed).

Note:presence of menstruation, established intrauterine device, breastfeeding are not a contraindication to MRI.

Research Safety Issues

During the examination, the tomograph creates a powerful magnetic field that can cause movement of metal objects in the body (implants, retainers, removable dentures, etc.), therefore, if they are present, MRI cannot be used. Also, metal objects can affect the image quality, which will lead to distortion of the result. You should inform your doctor about the presence of the listed items.

The generated magnetic field can damage hearing aids and pacemakers.

Also, do not leave the device within the range of operation. Cell phones, magnetic cards. Metal rings, chains and other jewelry should be removed in advance in another room; usually there is a locker room with a safe for this purpose.

To avoid errors when analyzing the obtained images, the radiologist should have full information about the patient being studied . He is provided with:

medical history (extract), or outpatient card;
data from previous studies – computed tomography, and/or MRI.

No special preparatory activities They don’t do it the day before. The diet does not change. If an MRI of the intestines and abdominal organs is performed, you should refrain from eating solid food for several hours before the procedure.

Note:the study lasts from 20 to 60 minutes, depending on the method used. Therefore, you should empty your bowels beforehand and bladder.

During an MRI session, it is best to be dressed in natural fabrics; women are not recommended to use cosmetics, as the substances contained in them can affect the quality of the image.

Young children are given sedatives or even light anesthesia.

During the procedure, the patient wears special headphones or earplugs to reduce the noise load of the procedure. They will be used to communicate with medical personnel.

In addition, the patient will have an alarm device in his hand in case of unexpected sensations or reactions. Through it you can send an emergency signal to office workers.

What might you feel during an MRI?

It is important to know that during the examination the patient does not experience any pain. You just need to lie quietly, breathe evenly and not move. In some patients, the tomograph causes mental discomfort associated with the fear of closed spaces. During the study, such patients are allowed to be present loved one.

Lotin Alexander, medical columnist

Magnetic resonance imaging, or MRI for short, is a modern, safe and effective method diagnostics, allowing specialists to accurately determine the disease, pathology, injury or other disorders in the functioning of organs human body. Simply put, MRI is a scan, but with a different principle of operation, unlike radiography and CT.

Magnetic resonance imaging has a number of advantages over other diagnostic methods, as well as indications and contraindications for its use. A preliminary interpretation of the study results is carried out by a radiologist after the procedure. A more accurate and specific explanation of the MRI results is made by the doctor, taking into account the anamnesis and clinical picture.

Operating principle and advantages over other diagnostic methods

The operating principle of an MRI scanner is based on the characteristics of the magnetic field and the magnetic properties of body tissue. Thanks to the interaction of nuclear magnetic resonance and the nuclei of hydrogen atoms, during the examination a layer-by-layer image of the organs of the human body is displayed on the computer screen. In this way, it is possible not only to differentiate some organs and tissues from others, but also to record the presence of even minor disorders, tumor and inflammatory processes.

The operating principle of MRI allows you to accurately assess the condition of soft tissues, cartilage, brain, organs, spinal discs, ligaments - those structures that are largely composed of fluid. At the same time, MRI is used less in medicine if it is necessary to study bones or tissues of the lungs, intestines, stomach - structures in which the water content is minimal.

Closed-type tomography apparatus

Due to the way MRI works, there are a number of advantages of this type of research over others:

As a result of the examination, it is possible to obtain a detailed image. Therefore, this technique is considered the most effective for the early detection of tumors and foci of inflammation, the study of central nervous system disorders, musculoskeletal system, abdominal and pelvic organs, brain, spine, joints, blood vessels.
Magnetic tomography allows for diagnosis in places where CT is not effective due to overlap of the examined area bone tissue or due to the insensitivity of CT to changes in tissue density.
There is no ionizing radiation to the patient during the procedure.
It is possible to obtain not only an image of the structure of tissues, but also MRI indications of their functioning. For example, the speed of blood flow, current cerebrospinal fluid And brain activity recorded using functional magnetic resonance imaging.
Possibility of conducting contrast MRI. The contrast agent increases the diagnostic potential of the procedure.
MRI open type allow patients with fear of closed spaces to undergo examinations.

Another advantage is that errors are virtually eliminated when making a diagnosis. If the patient is concerned with the question: “Can MRI be wrong?”, then the answer is a little ambiguous. On the one side this procedure is one of the most precise methods diagnostics On the other hand, errors can occur at the stage of deciphering the results and making a diagnosis by the doctor.

Classification of modern magnetic tomographs

Most patients are wary of magnetic tomography machines because they do not know what to expect during the procedure and are afraid that they will become ill in a confined space. For other people, a standard study is not available due to their weight (more than 150 kg), the presence psychological disorders or childhood.

However, not everyone knows that modern scientists-technologists have long solved these problems by developing different types tomographs:

Closed type scanner;
Open type MRI scanner.

Most medical institutions have standard closed-type MRI machines, that is, those where the patient is in a “tunnel” during the examination. Such equipment is considered the most reliable, since the magnetic field strength in them is quite high.

But some clinics install open MRI. Such devices are considered not so reliable due to the low magnetic field strength. But every year technologies are improving, and an open-type tomograph can no longer be classified as less informative or insufficiently powerful. Moreover, such a device has the following advantages:

The design of the tomograph does not require a sliding table, which makes it possible to examine patients with significant body weight.
During the examination, the patient is not in a confined space. This can significantly reduce psychological discomfort, eliminate panic attacks and claustrophobia.
For some injuries, specific fixation of the limbs makes it impossible to place the patient in a closed-type tomograph. Therefore, open types of MRI are the only way to diagnose possible injuries internal organs, brain.

The ability to examine a patient using an open or closed tomograph significantly expands the capabilities of doctors in complex or unusual cases.

Indications for the procedure

Why is MRI done, and in what situations will this research method be effective? As already noted, magnetic tomography allows for the diagnosis of a wide range of diseases and conditions. All types of MRI studies and indications for their implementation can be classified depending on the organs/systems examined:

: impaired blood circulation in the brain, suspicion of tumor lesions, monitoring the state of the brain after surgical intervention, monitoring of possible relapses of tumor processes, suspicion of the presence of foci of inflammation, epilepsy, lesions due to arterial hypertension, head injury.
Temporomandibular joints: diagnosis of the condition of joint discs, assessment of effectiveness surgical treatment, malocclusion, preparation for orthodontic treatment.
Eyes: suspicion of a tumor, injury, inflammatory processes, diagnosis of the condition of the lacrimal glands after injury.
Area of the nose, mouth: sinusitis, preparatory manipulations before plastic surgery.
: various degenerative changes in the structure of the spine (for example, osteochondrosis), pinched nerve roots, congenital pathologies, injuries and assessment of the effectiveness of treatment after injuries, suspected tumor processes, osteoporosis.
Bones and joints: bones, soft tissues, joints – injuries (including sports), age-related changes, inflammatory processes, suspected tumors, muscle and tendon injuries, rheumatoid arthritis.
: pathology of internal organs.
: adenoma, prostate cancer, assessment of the spread of tumor lesions, preoperative preparation, assessment of the condition of the bladder, ureters, rectum, ovaries, scrotum, uterine fibroids, anomalies of the pelvic organs.

Also, if necessary, examination of the vessels of the brain, neck, chest area; arteries, veins, thyroid gland. If the presence of tumor lesions or metastases is suspected, the patient's entire body can be examined.

Also, indications for MRI may be a heart attack, defect or ischemic disease hearts.

Contraindications to the procedure

Many patients are concerned about whether there are contraindications to MRI. Of course, such limitations exist for tomography, as for any other medical procedure.

The entire list of contraindications to MRI can be divided into absolute and relative. Absolute ones include the presence of metal foreign body, prosthesis or electromagnetic implant, pacemaker. If an MRI with contrast is performed - renal failure and allergy to contrast agent.

The presence of these factors makes the procedure absolutely impossible. Under relative contraindications refers to conditions or circumstances that may pass/change over time, and the examination becomes possible.

Relative contraindications:

First 3 months.
Mental problems, schizophrenia, claustrophobia, panic states.
Severe illnesses in the stage of decompensation.
The patient has tattoos that were made using dyes based on metal compounds.
Severe pain, as a result of which the person cannot remain completely still.
State of intoxication - alcohol or drugs.

Does it childhood patient is a contraindication and is it possible to do MRI for children, if so - at what age? Experts answer these questions that childhood is not an obstacle to conducting research. That is, MRI is done even on newborn babies. However, with small children there is another problem - it is very difficult to force them to remain still. Especially for a long time, especially in a confined space. There are several solutions to this problem, for example, a preliminary conversation with the child or the use of anesthesia. MRI examinations under anesthesia are also performed on adults in cases where the procedure is absolutely necessary, but the person suffers from claustrophobia or panic attacks.

Preparatory activities

General preparation for MRI is an important stage of the study that cannot be ignored. The success of the procedure and the accuracy of the results depend on how accurately the patient follows the recommendations of specialists.

Preparation for the study begins with a mandatory consultation with a therapist. The doctor will clarify your medical history, conduct an external examination, clarify the issue of contraindications, tell you in detail how an MRI is done, and give directions for examining specific problem areas.

Preparing for an MRI also includes assessing your own condition. The patient must be prepared to be in a closed, noisy space for some time. If a person assumes that he may begin to panic, he should enlist the support of a loved one in advance. A relative or spouse will also help you get home after the procedure if the patient is given sedatives to calm down. MRI under anesthesia also requires the presence of a loved one who will take the patient home after the examination.

MRI preparation includes removing (from yourself and from clothing) all metal objects - pins, piercings, earrings and other jewelry, removable implants and dentures, hairpins, underwear with metal inserts, etc.

Before the procedure, you need to go to the toilet, you should not drink alcohol or drugs. Is it possible to eat before an MRI or take regular medications? Yes, if there is an examination of the brain, joints, eyes, nasopharynx or spine.

Some types of tomographic examinations require special preparation for MRI.

For example, before examining the pelvic organs, you need to urinate 3 hours before the procedure and not do it again. 60 minutes before the session, drink half a liter of plain water, so the bladder will be half full, which is required for correct diagnosis. The night before, you need to completely cleanse the intestines with an enema or laxative.

MRI of the abdominal organs is done only on an empty stomach, so the question of whether you can eat before the procedure is not appropriate in this case. Exceptions are situations when the session cannot be held in the morning. In this case, it is permissible to have a very light breakfast. Cleansing the intestines the day before and taking antispasmodics 30 minutes before the session is very advisable.

Preparing children for magnetic tomography examination

Physically, children are prepared for the procedure in the same way as adults. If the child is already at an age when he understands what is wanted from him and obeys his parents (6-7 years old), you need to tell him how to prepare for an MRI on his own. If necessary, help.

Preparing a child for an MRI of the brain using an open-type device

Psychological preparation of the child is a necessary preliminary stage. You need to tell your child why an MRI is done, what awaits him during this procedure, what sensations may arise, how to suppress negative thoughts and fears. You also need to warn the child about how long it takes to do an MRI and that during this time he should be as motionless as possible.

If parents see that the child is not psychologically ready, feels strong fear or there are other contributing factors ( strong pain, epilepsy, seizures), you may have to use deep sedation or general anesthesia.

How does a magnetic resonance imaging session work?

To ensure that no unexpected or unpleasant surprises occur during the examination session, the patient needs to have a rough idea of how an MRI is performed. The standard procedure includes the following steps:

The patient is asked to undress and remove all foreign objects from the body, including the wig, removable dentures And hearing aid, decorations, etc. The doctor will give you a disposable cape for your change.
The patient takes horizontal position on a special sliding table. Then the table slides into the apparatus tunnel. With modern tomographs, variations of this stage are possible. For example, in the case of using an open-type tomograph or a device requiring a sitting position.
How long an MRI takes depends on the type of examination. On average - from 20 to 120 minutes. All this time, the patient must maintain absolute immobility of the area of the body being examined.
During a tomography session, the patient hears noise or buzzing, and may experience a slight vibration. To make it easier to be in a confined space, it is better to close your eyes and relax as much as possible.

After the end of the session, the patient may be asked to wait for some time to make sure that everything was successful, the data obtained is sufficient and no additional manipulations are required. After this, personal belongings and clothes are returned to the patient - the magnetic resonance imaging session is over.

Special attention is required to specify how the MRI procedure takes place in the case of the use of anesthesia or contrast agents.

Features of MRI in patients under anesthesia

MRI under anesthesia can be of two types:

Deep sedation using modern tranquilizer drugs. Helps significantly calm the patient, relieve anxiety, and stop panic attacks.
Anesthesia, which is done using intravenous injection or inhalation. This method may require additional ventilation and the connection of vital signs monitoring devices.

Typically, the effect of anesthesia wears off within 30-60 minutes after the end of the study session. Before anesthesia, you should not eat for 9 hours, and for children under 6 years old - 6 hours. You can only drink clean water and tea, in small portions. Stop taking liquids 2 hours before the procedure.

After anesthesia, you can leave the clinic only with an accompanying person, independent control vehicle Absolutely forbidden.

Magnetic resonance imaging with contrast

Injector for administering contrast agent during the examination

What is MRI with contrast? This is the same procedure as a standard MRI, only to increase the information content of the procedure, a safe, non-toxic substance is injected into the patient’s vein. In most cases, this is necessary when diagnosing tumor lesions. In this way, it is possible to conduct the most comprehensive study, studying in detail the size of the tumor, its structure and extent of spread.

However, a tumor is not the only reason for this type of procedure. There are a number of indications for contrast-enhanced examinations.

Contraindications: pregnancy, lactation, allergies (very rare cases).

The patient does not experience any consequences or adverse reactions after a tomography session with contrast.

Results of magnetic resonance examination

What the MRI shows, that is, the examination results, will be ready within 1 or 2 days. If everything is normal in the body, then the results will show that all organs and tissues of the body are in their places, have standard sizes, shape, structure, density. Magnetic resonance imaging will also show that there are no malignant or benign tumors, bleeding, blood clots, inflammatory or infectious processes in the body.

Radiologists make a conclusion on an MRI study

If the doctor discovers any violations, this will be reflected in the conclusion and medical history.

Let's sum it up

MRI is the most modern, one of the most accurate and safe non-invasive methods research human body. A magnetic tomography session is absolutely painless and is suitable for examining even small children. What an MRI can show helps a doctor diagnose any health problem or confirm the absence of one.