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Side effects of mri test. MRI Risks and Side Effects: Understanding the Safety of Magnetic Resonance Imaging

What are the potential risks associated with MRI scans. How can patients prepare for an MRI examination. What safety precautions are taken during an MRI procedure. Who should avoid undergoing an MRI scan. What are the possible side effects of MRI contrast agents.

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What is Magnetic Resonance Imaging (MRI)?

Magnetic Resonance Imaging, commonly known as MRI, is a non-invasive medical imaging technique that uses powerful magnets and radio waves to create detailed images of the body’s internal structures. Unlike X-rays or CT scans, MRI does not use ionizing radiation, making it a safer option for many patients.

An MRI scanner is a large, cylindrical machine that generates a strong magnetic field around the patient. This field, combined with radiofrequency pulses, temporarily alters the alignment of hydrogen atoms in the body. As these atoms realign, they emit radio signals that are detected and processed by a computer to create high-resolution images of organs, tissues, and other structures.

How does an MRI work?

The MRI process can be broken down into several steps:

  1. The patient lies on a movable table that slides into the MRI scanner.
  2. The scanner creates a strong magnetic field around the body.
  3. Radio waves are pulsed through the body, causing hydrogen atoms to temporarily change their alignment.
  4. As the atoms return to their normal alignment, they emit radio signals.
  5. The MRI machine’s computer detects these signals and uses them to create detailed cross-sectional images.
  6. These images can be viewed from different angles and compiled to form 3D representations of the body’s structures.

Common Uses and Applications of MRI Scans

MRI scans are versatile diagnostic tools used to examine various parts of the body. They are particularly useful for imaging soft tissues and can help detect a wide range of conditions. Some common applications of MRI include:

  • Brain and spinal cord disorders
  • Joint and musculoskeletal problems
  • Cardiovascular diseases
  • Abdominal and pelvic conditions
  • Cancer detection and monitoring
  • Breast imaging

MRI’s ability to provide detailed images without using radiation makes it an invaluable tool in modern medicine, allowing doctors to diagnose and monitor various conditions with greater accuracy and safety.

Preparing for an MRI Examination

Proper preparation is crucial for ensuring a successful and comfortable MRI experience. Patients should be aware of the following guidelines:

Before the scan:

  • Inform your doctor of any medical conditions, allergies, or implants you may have.
  • Remove all metal objects, including jewelry, watches, and electronic devices.
  • Wear comfortable, loose-fitting clothing without metal fasteners.
  • Follow any specific instructions provided by your healthcare provider regarding food and medication intake.

During the scan:

  • Remain as still as possible to ensure clear images.
  • Breathe normally unless instructed otherwise.
  • Communicate with the technologist through the intercom if you experience any discomfort.

It’s important to note that some patients may require special preparations, such as fasting or discontinuing certain medications. Always consult with your healthcare provider for personalized instructions.

Safety Precautions and Contraindications for MRI Scans

While MRI is generally considered safe, certain precautions must be taken to ensure patient safety. Some individuals may not be suitable candidates for MRI scans due to various factors.

Who should avoid MRI scans?

The following groups of people may need to avoid MRI scans or require special precautions:

  • Individuals with certain metallic implants or devices
  • Pregnant women, especially in the first trimester
  • People with severe claustrophobia
  • Patients with kidney problems (when contrast agents are used)

It’s crucial to inform your healthcare provider of any medical conditions, implants, or concerns you may have before undergoing an MRI scan. In some cases, alternative imaging methods may be recommended.

Potential Risks and Side Effects of MRI Scans

While MRI is generally considered a safe procedure, there are some potential risks and side effects that patients should be aware of:

Magnetic field interactions:

The strong magnetic field used in MRI can interact with metal objects, potentially causing them to move or heat up. This is why it’s crucial to remove all metal items before the scan and inform your doctor of any implants or devices in your body.

Claustrophobia and anxiety:

Some patients may experience anxiety or claustrophobia during the scan due to the confined space of the MRI machine. Open MRI machines or sedation may be options for those with severe claustrophobia.

Noise-related discomfort:

MRI scanners produce loud knocking or thumping noises during the scan, which can be uncomfortable for some patients. Earplugs or headphones are typically provided to minimize this discomfort.

Allergic reactions to contrast agents:

In rare cases, patients may experience allergic reactions to the gadolinium-based contrast agents used in some MRI scans. Symptoms can range from mild (such as hives or itching) to severe (such as difficulty breathing or anaphylaxis).

Understanding MRI Contrast Agents and Their Effects

Contrast agents are sometimes used during MRI scans to enhance the visibility of certain tissues or blood vessels. The most commonly used contrast agents for MRI are gadolinium-based compounds.

How do MRI contrast agents work?

Gadolinium-based contrast agents work by altering the magnetic properties of nearby water molecules, which results in a brighter signal on the MRI images. This enhanced contrast can help radiologists detect and characterize various abnormalities more accurately.

Potential side effects of gadolinium-based contrast agents:

  • Nausea and vomiting
  • Headache
  • Dizziness
  • Itching or rash
  • Feeling of warmth or coldness at the injection site

In rare cases, more serious side effects can occur, such as nephrogenic systemic fibrosis (NSF) in patients with severe kidney dysfunction. It’s important to discuss any concerns about contrast agents with your healthcare provider before the MRI scan.

Advances in MRI Technology and Future Developments

MRI technology continues to evolve, with ongoing research and development aimed at improving image quality, reducing scan times, and expanding its diagnostic capabilities. Some recent advancements and future prospects in MRI technology include:

Higher field strength magnets:

MRI scanners with higher magnetic field strengths (such as 7 Tesla and beyond) are being developed to provide even more detailed images and potentially reveal new information about various diseases and conditions.

Faster scanning techniques:

Researchers are working on methods to reduce MRI scan times without compromising image quality. This could lead to increased patient comfort and improved efficiency in healthcare settings.

Artificial intelligence integration:

AI algorithms are being developed to assist in image reconstruction, analysis, and interpretation, potentially improving diagnostic accuracy and efficiency.

Functional MRI (fMRI) advancements:

Ongoing research in functional MRI techniques is expanding our understanding of brain function and may lead to new applications in neurology, psychiatry, and cognitive science.

MRI-guided interventions:

The development of MRI-compatible surgical tools and real-time imaging techniques is opening up new possibilities for minimally invasive, image-guided procedures.

As MRI technology continues to advance, it is likely to play an increasingly important role in medical diagnosis, treatment planning, and research across various fields of medicine.

Managing Anxiety and Claustrophobia During MRI Scans

For some patients, the prospect of undergoing an MRI scan can be anxiety-inducing, particularly due to the confined space of the scanner. However, there are several strategies that can help manage these concerns:

Open and wide-bore MRI scanners:

Many facilities now offer open MRI machines or scanners with wider bores, which can be more comfortable for claustrophobic patients or those with larger body sizes.

Relaxation techniques:

Deep breathing exercises, meditation, or visualization techniques can help reduce anxiety during the scan. Some facilities may offer guided relaxation through headphones during the procedure.

Sedation options:

For patients with severe anxiety or claustrophobia, mild sedatives may be prescribed to help them relax during the scan. This should be discussed with the healthcare provider in advance.

Bringing a support person:

Some facilities allow a friend or family member to stay in the room during the scan, which can provide comfort and reassurance to anxious patients.

Communication with the technologist:

Patients can communicate with the MRI technologist throughout the scan via an intercom system. This allows for immediate assistance if needed and can help alleviate anxiety.

By addressing anxiety and claustrophobia concerns proactively, healthcare providers can help ensure a more comfortable and successful MRI experience for their patients.

Magnetic Resonance Imaging (MRI) | Stanford Health Care

What Is Magnetic Resonance Imaging (MRI)?

A magnetic resonance (REZ-oh-nans) imaging scan is usually called an MRI. An MRI does not use radiation (X-rays) and is a noninvasive medical test or examination. The MRI machine uses a large magnet and a computer to take pictures of the inside of your body. Each picture or “slice” shows only a few layers of body tissue at a time. The pictures can then be examined on a computer monitor.

Pictures taken this way may help caregivers find and see problems in your body more easily. The scan usually takes between 15 to 90 minutes. Including the scan, the total examination time usually takes between 1.5 to 3 hours.

A substance called gadolinium is injected into a vein to help the physicians see the image more clearly. The gadolinium collects around cancer cells so they show up brighter in the picture. Sometimes a procedure called magnetic resonance spectroscopy (MRS) is done during the MRI scan. An MRS is used to diagnose tumors based on their chemical make-up.

How does MRI work?

The MRI machine is a large, cylindrical (tube-shaped) machine that creates a strong magnetic field around the patient. This magnetic field, along with a radiofrequency, alters the hydrogen atoms’ natural alignment in the body.

A magnetic field is created and pulses of radio waves are sent from a scanner. The radio waves knock the nuclei of the atoms in the body out of their normal position; as the nuclei realign back into proper position, they send out radio signals.

These signals are received by a computer that analyzes and converts them into an image of the part of the body being examined. This image appears on a viewing monitor. Some MRI machines look like narrow tunnels, while others are more open.

MRI may be used instead of a CT scan in situations where organs or soft tissue are being studied, because with MRI scanning bones do not obscure the images of organs and soft tissues, as does CT scanning.

Other related procedures that are used to assess the heart may include:

MRI scan – How it’s performed

A magnetic resonance imaging (MRI) scan is a painless procedure that lasts 15 to 90 minutes, depending on the size of the area being scanned and the number of images being taken.

Before the scan

On the day of your MRI scan, you should be able to eat, drink and take any medication as usual, unless you’re advised otherwise.

In some cases, you may be asked not to eat or drink anything for up to 4 hours before the scan, and sometimes you may be asked to drink a fairly large amount of water beforehand. This depends on the area being scanned.

When you arrive at the hospital, you’ll usually be asked to fill in a questionnaire about your health and medical history. This helps the medical staff to ensure you have the scan safely.

Read more about who can and can’t have an MRI scan.

Once you have completed the questionnaire, you’ll usually be asked to give your signed consent for the scan to go ahead.

As the MRI scanner produces strong magnetic fields, it’s important to remove any metal objects from your body.

These include:

  • watches
  • jewellery, such as earrings and necklaces
  • piercings, such as ear, nipple and nose rings
  • dentures (false teeth)
  • hearing aids
  • wigs (some wigs contain traces of metal)

Any valuables can usually be stored in a secure locker.

Depending on which part of your body is being scanned, you may need to wear a hospital gown during the procedure.

If you don’t need to wear a gown, you should wear clothes without metal zips, fasteners, buttons, underwire (bras), belts or buckles.

Contrast dye

Some MRI scans involve having an injection of contrast dye. This makes certain tissues and blood vessels show up more clearly and in greater detail.

Sometimes the contrast dye can cause side effects, such as:

  • feeling or being sick
  • a skin rash
  • a headache
  • dizziness

These side effects are usually mild and don’t last very long.

It’s also possible for contrast dye to cause tissue and organ damage in people with severe kidney disease.

If you have a history of kidney disease, you may be given a blood test to determine how well your kidneys are functioning and whether it’s safe to proceed with the scan.

You should let the staff know if you have a history of allergic reactions or any blood clotting problems before having the injection.

Anaesthesia and sedatives

An MRI scan is a painless procedure, so anaesthesia (painkilling medication) isn’t usually needed.

If you’re claustrophobic, you can ask for a mild sedative to help you relax. You should ask your GP or consultant well in advance of having the scan.

If you decide to have a sedative during the scan, you’ll need to arrange for a friend or family member to drive you home afterwards, as you won’t be able to drive for 24 hours.

Babies and young children may be given a general anaesthetic before having an MRI scan.

This is because it’s very important to stay still during the scan, which babies and young children are often unable to do when they’re awake.

During the scan

An MRI scanner is a short cylinder that’s open at both ends. You’ll lie on a motorised bed that’s moved inside the scanner.

You’ll enter the scanner either head first or feet first, depending on the part of your body being scanned.

In some cases, a frame may be placed over the body part being scanned, such as the head or chest.

This frame contains receivers that pick up the signals sent out by your body during the scan and it can help to create a better-quality image.

A computer is used to operate the MRI scanner, which is located in a different room to keep it away from the magnetic field generated by the scanner.

The radiographer operates the computer, so they’ll also be in a separate room to you.

But you’ll be able to talk to them, usually through an intercom, and they’ll be able to see you at all times on a television monitor.

A friend or family member may be allowed to stay with you while you’re having your scan. Children can usually have a parent with them.

Anyone who stays with you will be asked if they have a pacemaker or any other metal objects in their body.

They’ll also have to follow the same guidelines regarding clothing and the removal of metallic objects.

To avoid the images being blurred, it’s very important to keep the part of your body being scanned still throughout the whole of the scan until the radiographer tells you to relax.

A single scan may take from a few seconds to 3 or 4 minutes. You may be asked to hold your breath during short scans.

Depending on the size of the area being scanned and how many images are taken, the whole procedure will take 15 to 90 minutes.

The MRI scanner will make loud tapping noises at certain times during the procedure. This is the electric current in the scanner coils being turned on and off. You’ll be given earplugs or headphones to wear.

You’re usually able to listen to music through headphones during the scan if you want to, and in some cases you can bring your own CD.

You’ll be moved out of the scanner when your scan is over.

After the scan

An MRI scan is usually carried out as an outpatient procedure. This means you won’t need to stay in hospital overnight.

After the scan, you can resume normal activities immediately. But if you have had a sedative, a friend or relative will need to take you home and stay with you for the first 24 hours.

It’s not safe to drive, operate heavy machinery or drink alcohol for 24 hours after having a sedative.

Your MRI scan needs to be studied by a radiologist (a doctor trained in interpreting scans and X-rays) and possibly discussed with other specialists. 

This means it’s unlikely you’ll get the results of your scan immediately.

The radiologist will send a report to the doctor who arranged the scan, who will discuss the results with you.

It usually takes a week or two for the results of an MRI scan to come through, unless they’re needed urgently.

Page last reviewed: 09 August 2018
Next review due: 09 August 2021

MRI Scan | Procedure, Uses, Side-Effects | Tests & Health

What is an MRI scan?

MRI stands for magnetic resonance imaging. An MRI scan uses a strong magnetic field and radio waves to create pictures on a computer screen. It can show tissues, organs and other structures inside your body.

This image is an MRI scan of a brain. The person’s eyeballs can be seen at the top of the picture.

MRI scan

By Ptrump (Own work) via Wikimedia Commons

How does an MRI scan work?

Your body contains millions of hydrogen atoms. When you are in an MRI scanner:

  • A strong magnetic field aligns particles called protons which are within the hydrogen atoms. All the protons line up in parallel to the magnetic field, like tiny magnets. (Normally the millions of protons all lie in random directions.)
  • Then short bursts of radio waves are sent from the scanner into your body. The radio waves knock the protons from their position.
  • When the burst of radio waves stop, the protons realign back into place. As they do so they emit radio signals. The protons in different tissues of the body realign at different speeds. Therefore, the signal emitted from different body tissues varies. So, for example, softer tissues can be distinguished from harder tissues on the basis of the signals sent.
  • These signals are detected by a receiving device in the scanner.
  • The receiving device transmits the signals to a computer. The computer creates a picture based on the radio signals emitted from the body.

What does an MRI scan involve?

The MRI scanner is like a tunnel about 1.5 metres long, surrounded by a large circular magnet. You lie on a couch which then slides into the scanner. A ‘receiving device’, like an aerial, is placed behind, or around, the part of the body being examined. This detects the tiny radio signals emitted from your body. When each ‘picture’ is being taken you need to keep still for a few minutes, otherwise the scan picture may be blurred.

By Jan Ainali (own work) via Wikimedia Commons.

The scan itself is painless. The whole procedure can take 15-40 minutes. It may be a little uncomfortable lying still on the couch for this time. Small children may need a general anaesthetic to keep them still long enough for the pictures to be taken. Where you lie is quite enclosed and some people may find this very unsettling. If you have a fear of confined spaces (claustrophobia) you should discuss this with your doctor before you go for the scan. Some parts of the country have access to ‘open’ scan machines. However, they are not widely available.

In some cases, an injection of a special contrast dye is given into the bloodstream via a vein on the arm. This helps to give clearer pictures of certain tissues or organs being examined.

The radiographer sits in the control room next to the scanner and observes through the window. However, you can talk to them, usually via an intercom, and you will be observed at all times on a monitor.

The scanner is noisy so you will be given some headphones or earplugs to protect your ears from the noise. Quite often you can listen to the radio through the headphones or bring a CD to listen to.

What is an MRI scan for?

An MRI scan can create clear pictures of most parts of the body. So, it is useful for all sorts of reasons where other tests (such as X-rays) do not give enough information required.

It is commonly used to obtain detailed pictures of the brain and spinal cord, to detect abnormalities and tumours. Even torn ligaments around joints can be detected by an MRI scan. So it is being used more and more following sports injuries.

MRI uses

Brain: MRI is the first-choice investigation for brain tumours, as it produces clearer images than computerised tomography (CT) and shows hard-to-reach areas of the brain. There is clear contrast between grey and white matter parts of the brain and this makes MRI the best choice for many other conditions, including multiple sclerosis, stroke, Alzheimer’s disease and epilepsy.

Musculoskeletal system: here, MRI is used to look at the spine – to assess joint disease and soft tissue tumours.

Gastrointestinal system: MRI allows non-invasive assessment of inflammatory bowel disease and bowel tumours. It can also look at problems in the liver and pancreas.

Blood vessels and the heart: this is called magnetic resonance angiography (MRA) and it generates pictures of the arteries to look for abnormal narrowing or vessel wall dilatations (those at risk of bursting). MRA is often used to evaluate the arteries of the neck and brain, the thoracic and abdominal aorta, the renal arteries, and the legs. It might also be used to assess congenital heart disease.

What preparation do I need to do before an MRI scan?

Usually very little. Your local hospital should give you information about what is required before you come for the scan.

The MRI scanner uses an extremely strong magnet, so people with certain types of medical implant cannot be scanned. This is because the magnet can potentially move medical devices with metal in them, or affect their function.

Therefore, before you enter the scanning area you should be asked if you have any medical devices in your body. You may have to fill in a safety questionnaire that asks about things that may contain metal. The following is not a definitive list but may help to remind you of the type of things radiographers need to know about:

  • Internal (implanted) defibrillator or pacemaker.
  • Ear (cochlear) implant.
  • Surgical clips such as those used on brain aneurysms.
  • Artificial heart valves.
  • Implanted medicine infusion ports.
  • Artificial limbs or metallic joints.
  • Implanted nerve stimulators.
  • Pins, screws, plates, stents or surgical staples.

It is also important to tell the radiographer if you have ever had any metal fragments lodged in your eyes or your body. In some cases you may need an X-ray before an MRI scan, to make sure you are safe to enter the scanner.

What are the possible side-effects of an MRI scan?

MRI scans are painless and thought to be safe. MRI scans do not use X-rays so the possible concerns associated with X-ray pictures and CT scans (which use X-rays) are not associated with MRI scans.

However:

  • Rarely, some people have reactions to the contrast dye which is sometimes used.
  • Pregnant women are usually advised not to have an MRI scan unless it is urgent. Although the scan is thought to be safe, the long-term effects of strong magnetic fields on a developing baby are not yet known.

What can I expect after the scan?

There are no after effects from the scan. You can return to your normal activities as soon as the scan is over. The scan pictures are studied by a specialist who interprets them – a radiologist – who sends a report to the doctor who requested the scan. It is usual to have to wait for at least two weeks before hearing about your results. If there are any urgent findings, the specialist will be informed as soon as possible.

What It Is and Why It’s Done

What Is an MRI?

Magnetic resonance imaging (MRI) is a test that uses powerful magnets, radio waves, and a computer to make detailed pictures of the inside of your body.

Your doctor can use this test to diagnose you or to see how well you’ve responded to treatment. Unlike X-rays and computed tomography (CT) scans, MRIs don’t use the damaging ionizing radiation of X-rays.

MRI Uses

An MRI helps a doctor diagnose a disease or injury, and it can monitor how well you’re doing with a treatment. MRIs can be done on different parts of your body. It’s especially useful for looking at soft tissues and the nervous system.

An MRI of the brain and spinal cord can help find many things, including:

An MRI of the heart and blood vessels looks for:

An MRI of the bones and joints looks for:

MRIs can also be done to check the health of these organs:

A special kind of MRI called a functional MRI (fMRI) maps brain activity.

This test looks at blood flow in your brain to see which areas become active when you do certain tasks. An fMRI can detect brain problems, such as the effects of a stroke, or it can be used for brain mapping if you need brain surgery for epilepsy or tumors. Your doctor can use this test to plan your treatment.

Risks of MRI

Pregnant women shouldn’t get an MRI during their first trimester unless they absolutely need the test. The first trimester is when the baby’s organs develop. You also shouldn’t get contrast dye when you’re pregnant.

Don’t get contrast dye if you’ve had an allergic reaction to it in the past or you have severe kidney disease.

Certain people with metal inside their body can’t get this test, including those with:

  • Some clips used to treat brain aneurysms
  • Pacemakers and cardiac defibrillators
  • Cochlear implants
  • Certain metal coils placed in blood vessels

MRI Preparation

Before your MRI, let your doctor know if you:

  • Have any health problems, such as kidney or liver disease
  • Recently had surgery
  • Have any allergies to food or medicine, or if you have asthma
  • Are pregnant, or might be pregnant

No metal is allowed in the MRI room, because the magnetic field in the machine can attract metal. Tell your doctor whether you have any metal-based devices that might cause problems during the test. These can include:

  • Artificial heart valves
  • Body piercings
  • Cochlear implants
  • Drug pumps
  • Fillings and other dental work
  • Implanted nerve stimulator
  • Insulin pump
  • Metal fragments, such as a bullet or shrapnel
  • Metal joints or limbs
  • Pacemaker or implantable cardioverter-defibrillator (ICD)
  • Pins or screws

If you have tattoos, talk with your doctor. Some inks contain metal.

On the day of the test, wear loose, comfortable clothing that doesn’t have snaps or other metal fasteners. You might need to take off your own clothes and wear a gown during the test.

Remove all of these before you go into the MRI room:

If you don’t like enclosed spaces or you’re nervous about the test, tell your doctor. You may be able to have an open MRI or get medicine to relax you before the test.

MRI Equipment

A typical MRI machine is a large tube with a hole at both ends. A magnet surrounds the tube. You lie on a table that slides all the way into the tube.

In a short-bore system, you are not totally inside the MRI machine. Only the part of your body that’s being scanned is inside. The rest of your body is outside the machine.

An open MRI is open on all sides. This type of machine may be best if you have claustrophobia — a fear of tight spaces — or you’re very overweight. The quality of images from some open MRI machines isn’t as good as it is with a closed MRI.

During an MRI

Before some MRIs, you’ll get contrast dye into a vein in your arm or hand. This dye helps the doctor more clearly see structures inside your body. The dye often used in MRIs is called gadolinium. It can leave a metal taste in your mouth.

You will lie on a table that slides into the MRI machine. Straps might be used to hold you still during the test. Your body might be completely inside the machine. Or, part of your body may stay outside the machine.

The MRI machine creates a strong magnetic field inside your body. A computer takes the signals from the MRI and uses them to make a series of pictures. Each picture shows a thin slice of your body.

You might hear a loud thumping or tapping sound during the test. This is the machine creating energy to take pictures inside your body. You can ask for earplugs or headphones to muffle the sound.

You might feel a twitching sensation during the test. This happens as the MRI stimulates nerves in your body. It’s normal, and nothing to worry about.

The MRI scan should take 20-90 minutes.

After an MRI

You can usually go home after an MRI and get back to your normal routine. If you had medicine to help you relax, you’ll stay in the imaging center until you’re fully awake. You’ll also need someone to drive you home.

MRI Side Effects

Contrast dye helps your doctor better see what’s going on, and for most people it doesn’t cause any problems. But it can cause an allergic reaction in some people. There are steps doctors take to treat them.

Your doctor likely won’t use it on you if you’re pregnant, even though there’s no evidence it could harm a fetus. Your doctor may check your kidney function before the test. People with severe kidney disease are at risk of a rare disease called nephrogenic sclerosing fibrosis.

There’s a chance some of the dye may stay in your body and build up in the brain and other organs. It’s not clear yet if this buildup is harmful. The FDA hasn’t restricted its use.

MRI Results

A specially trained doctor called a radiologist will read the results of your MRI and send the report to your doctor.

Your doctor will explain the meaning of your test results and what to do next.

MRI Scan: Prep, What to Expect, Side Effects

Patient safety tips prior to the procedure

Because of the strong magnetic field used during the exam, certain conditions may prevent you from having a MR procedure. When scheduling your appointment and prior to your exam, please alert our staff and technologist to the following conditions that may apply to you. The radiology staff will let then let you know whether you can have the MRI exam and whether the exam needs to be modified for your particular condition.

  • Pacemaker
  • Pregnancy
  • Claustrophobia
  • History of kidney problems
  • Skin tattoos
  • Neurostimulators (TENS-unit)
  • Implanted drug infusion device (i.e., insulin pump)
  • Exposure of metal fragments to your eye
  • Artificial heart valves
  • Aneurysm clips
  • Cochlear implants
  • Metallic implants and prosthesis
  • Vascular stent or stent graft
  • History as a metal worker
  • Shrapnel or bullet wounds
  • Dorsal column stimulators
  • Allergy to iodine, or gadolinium
  • History of diabetes
  • Other conditions you believe to be relevant
Other Tips
  • Please leave your valuables at home, including jewelry, to prevent it from being lost or stolen, for they have to be removed prior to entering the scan room.
  • Please let us know if you need interpreting services, this can be arranged for you.
  • Please bring a list of your current medications.
  • If you experience anxiety related to claustrophobia, your doctor may prescribe an oral medication for you to take with you for your MRI appointment.

What can I expect before my MRI exam?

There is little preparation for an MRI exam. Take your daily medications as you normally would, unless instructed otherwise. There are few dietary restrictions for an MRI. For those exams, you will be notified of the requirements.

  • Please arrive at least 30 minutes prior to your exam and check in with the receptionist. You will need to complete the MRI screening form.
  • To eliminate possible MR safety issues, you will be asked to change into a hospital gown. A locker will be supplied to secure your belongings.
  • A technologist will verify your identification and the requested exam. Your screening form will be reviewed by the technologist in consultation with the radiologist if indicated. If MRI contrast is indicated for the exam, an IV catheter will be inserted in your arm by a nurse or technologist.

What can I expect during my MRI scan?

  • The duration of the procedure will vary but the average is 45 minutes to one hour per body part. 
  • You will be required to lie still during the actual MR scanning. Depending on the body part that is being examined, you may be instructed to hold your breath for up to 30 seconds.
  • The magnet is permanently open on both ends. It is well lit and there is a fan for patient comfort. There is also a two way intercom system for communication between patient and technologist. The part of the body being scanned will be placed in the middle of the magnet.
  • During the actual imaging, you will hear a loud intermittent banging noise. You will be provided with earplugs or head phones to minimize the noise during the procedure. 
  • The technologist will also provide you with an alarm button to alert the technologist of any discomfort you may experience at any point during the MRI exam. 
  • Some MRI exams require an injection of intravenous MRI contrast. Inform the technologist if you experience any discomfort during the injection.

What can I expect after my MRI scan?

  • If a dye injection is used, the IV is removed from the arm before you go home.
  • Allergic reaction from gadolinium dye is extremely rare. However, if you experience symptoms such as rash, hives, or shortness of breath, you should notify the technologist immediately if you are still at the imaging facility, or call your doctor or go to the nearest hospital if you have already left the imaging facility.
  • In the event that sedation is needed (such as for claustrophobia), you will be sent home once awake and alert. If you receive sedation, someone must drive you home.

How can I help prepare my child for an MRI scan?

MRI examinations require that the patient hold still for long periods of time. We provide MRI-compatible CinemaVision goggles (which are found in very few imaging centers) so that our young patients can watch movies during their MRI procedure. Patients can either choose a movie from our movie list or bring one from home. Watching an entertaining movie helps children remain comfortable and still, and it minimizes the need for anesthesia.

We invite our younger patients to watch this video to get ready for their MRI:

Head MRI (Magnetic Resonance Imaging)

Magnetic resonance imaging (MRI) of the head uses a powerful magnetic field, radio waves and a computer to produce detailed pictures of the brain and other cranial structures that are clearer and more detailed than other imaging methods. This exam does not use ionizing radiation and may require an injection of a contrast material called gadolinium, which is less likely to cause an allergic reaction than iodinated contrast material.

Tell your doctor about any health problems, recent surgeries or allergies and whether there’s a possibility you are pregnant. The magnetic field is not harmful, but it may cause some medical devices to malfunction. Most orthopedic implants pose no risk, but you should always tell the technologist if you have any devices or metal in your body. Guidelines about eating and drinking before your exam vary between facilities. Unless you are told otherwise, take your regular medications as usual. Leave jewelry at home and wear loose, comfortable clothing. You may be asked to wear a gown. If you have claustrophobia or anxiety, you may want to ask your doctor for a mild sedative prior to the exam.

What is MRI of the Head?

Magnetic resonance imaging (MRI) is a noninvasive test doctors use to diagnose medical conditions.

MRI uses a powerful magnetic field, radiofrequency pulses, and a computer to produce detailed pictures of internal body structures. MRI does not use radiation (x-rays).

Detailed MR images allow doctors to examine the body and detect disease.

Currently, MRI is the most sensitive imaging test of the head (particularly the brain) in routine clinical practice.

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What are some common uses of the procedure?

MR imaging of the head is performed for a number of abrupt onset or long-standing symptoms. It can help diagnose conditions such as:

  • developmental anomalies
  • hydrocephalus — dilatation of fluid spaces within the brain (ventricles)
  • causes of epilepsy (seizure)
  • infections
  • stroke
  • brain tumors
  • certain chronic conditions, such as multiple sclerosis
  • hemorrhage in selected trauma patients
  • disorders of the eye and inner ear
  • disorders of pituitary gland
  • vascular problems, such as an aneurysm (a bubble-like expansion of the vessel), arterial occlusion (blockage) or venous thrombosis (a blood clot within a vein)

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How should I prepare?

You will need to change into a hospital gown. This is to prevent artifacts appearing on the final images and to comply with safety regulations related to the strong magnetic field.

Guidelines about eating and drinking before an MRI vary between specific exams and facilities. Take food and medications as usual unless your doctor tells you otherwise.

Some MRI exams use an injection of contrast material. The doctor may ask if you have asthma or allergies to contrast material, drugs, food, or the environment. MRI exams commonly use a contrast material called gadolinium. Doctors can use gadolinium in patients who are allergic to iodine contrast. A patient is much less likely to be allergic to gadolinium than to iodine contrast. However, even if the patient has a known allergy to gadolinium, it may be possible to use it after appropriate pre-medication. For more information on allergic reactions to gadolinium contrast, please consult the ACR Manual on Contrast Media.

Tell the technologist or radiologist if you have any serious health problems or recent surgeries. Some conditions, such as severe kidney disease, may mean that you cannot safely receive gadolinium. You may need a blood test to confirm your kidneys are functioning normally.

Women should always tell their doctor and technologist if they are pregnant. MRI has been used since the 1980s with no reports of any ill effects on pregnant women or their unborn babies. However, the baby will be in a strong magnetic field. Therefore, pregnant women should not have an MRI in the first trimester unless the benefit of the exam clearly outweighs any potential risks. Pregnant women should not receive gadolinium contrast unless absolutely necessary. See the MRI Safety During Pregnancy page for more information about pregnancy and MRI.

If you have claustrophobia (fear of enclosed spaces) or anxiety, ask your doctor to prescribe a mild sedative prior to the date of your exam.

Leave all jewelry and other accessories at home or remove them prior to the MRI scan. Metal and electronic items are not allowed in the exam room. They can interfere with the magnetic field of the MRI unit, cause burns, or become harmful projectiles. These items include:

  • jewelry, watches, credit cards, and hearing aids, all of which can be damaged
  • pins, hairpins, metal zippers, and similar metallic items, which can distort MRI images
  • removable dental work
  • pens, pocketknives, and eyeglasses
  • body piercings
  • mobile phones, electronic watches, and tracking devices.

In most cases, an MRI exam is safe for patients with metal implants, except for a few types. People with the following implants may not be scanned and should not enter the MRI scanning area without first being evaluated for safety:

Tell the technologist if you have medical or electronic devices in your body. These devices may interfere with the exam or pose a risk. Many implanted devices will have a pamphlet explaining the MRI risks for that device. If you have the pamphlet, bring it to the attention of the scheduler before the exam. MRI cannot be performed without confirmation and documentation of the type of implant and MRI compatibility. You should also bring any pamphlet to your exam in case the radiologist or technologist has any questions.

If there is any question, an x-ray can detect and identify any metal objects. Metal objects used in orthopedic surgery generally pose no risk during MRI. However, a recently placed artificial joint may require the use of a different imaging exam.

Tell the technologist or radiologist about any shrapnel, bullets, or other metal that may be in your body. Foreign bodies near and especially lodged in the eyes are very important because they may move or heat up during the scan and cause blindness. Dyes used in tattoos may contain iron and could heat up during an MRI scan. This is rare. The magnetic field will usually not affect tooth fillings, braces, eyeshadows, and other cosmetics. However, these items may distort images of the facial area or brain. Tell the radiologist about them.

Anyone accompanying a patient into the exam room must also undergo screening for metal objects and implanted devices.

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What does the equipment look like?

The traditional MRI unit is a large cylinder-shaped tube surrounded by a circular magnet. You will lie on a table that slides into a tunnel towards the center of the magnet.

Some MRI units, called short-bore systems, are designed so that the magnet does not completely surround you. Some newer MRI machines have a larger diameter bore, which can be more comfortable for larger patients or those with claustrophobia. “Open” MRI units are open on the sides. They are especially helpful for examining larger patients or those with claustrophobia. Open MRI units can provide high quality images for many types of exams. Open MRI may not be used for certain exams. For more information, consult your radiologist.

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How does the procedure work?

Unlike x-ray and computed tomography (CT) exams, MRI does not use radiation. Instead, radio waves re-align hydrogen atoms that naturally exist within the body. This does not cause any chemical changes in the tissues. As the hydrogen atoms return to their usual alignment, they emit different amounts of energy depending on the type of tissue they are in. The scanner captures this energy and creates a picture using this information.

In most MRI units, the magnetic field is produced by passing an electric current through wire coils. Other coils are inside the machine and, in some cases, are placed around the part of the body being imaged. These coils send and receive radio waves, producing signals that are detected by the machine. The electric current does not come into contact with the patient.

A computer processes the signals and creates a series of images, each of which shows a thin slice of the body. The radiologist can study these images from different angles.

MRI is often able to tell the difference between diseased tissue and normal tissue better than x-ray, CT, and ultrasound.

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How is the procedure performed?

MRI exams may be done on an outpatient basis.

The technologist will position you on the moveable exam table. They may use straps and bolsters to help you stay still and maintain your position.

The technologist may place devices that contain coils capable of sending and receiving radio waves around or next to the area of the body under examination.

MRI exams generally include multiple runs (sequences), some of which may last several minutes. Each run will create a different set of noises.

For an MRI of the head, a device is positioned around the head.

If your exam uses a contrast material, a doctor, nurse, or technologist will insert an intravenous catheter (IV line) into a vein in your hand or arm. They will use this IV to inject the contrast material.

You will be placed into the magnet of the MRI unit. The technologist will perform the exam while working at a computer outside of the room. You will be able to talk to the technologist via an intercom.

When the exam is complete, the technologist may ask you to wait while the radiologist checks the images in case more are needed.

The technologist will remove your IV line after the exam is over and place a small dressing over the insertion site.

The entire examination is usually completed within 45 minutes.

The doctor may also perform MR spectroscopy during your exam. MR spectroscopy provides additional information on the chemicals present in the body’s cells. This may add about 15 minutes to the total exam time.

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What will I experience during and after the procedure?

Most MRI exams are painless. However, some patients find it uncomfortable to remain still. Others may feel closed-in (claustrophobic) while in the MRI scanner. The scanner can be noisy.

It is normal for the area of your body being imaged to feel slightly warm. If it bothers you, tell the radiologist or technologist. It is important that you remain perfectly still while the images are being taken. This is typically only a few seconds to a few minutes at a time. You will know when images are being recorded because you will hear and feel loud tapping or thumping sounds. The coils that generate the radio waves make these sounds when they are activated. You will be provided with earplugs or headphones to reduce the noise made by the scanner. You may be able to relax between imaging sequences. However, you will need to keep the same position as much as possible without moving.

You will usually be alone in the exam room. However, the technologist will be able to see, hear, and speak with you at all times using a two-way intercom. They will give you a “squeeze-ball” that alerts the technologist that you need attention right away. Many facilities allow a friend or parent to stay in the room if they have also been screened for safety.

Children will be given appropriately sized earplugs or headphones during the exam. Music may be played through the headphones to help pass the time. MRI scanners are air-conditioned and well-lit.

In some cases, IV injection of contrast material may be given before the images are obtained. The IV needle may cause you some discomfort and you may experience some bruising. There is also a very small chance of skin irritation at the site of the IV tube insertion. Some patients may have a temporary metallic taste in their mouth after the contrast injection.

If you do not require sedation, no recovery period is necessary. You may resume your usual activities and normal diet immediately after the exam. On very rare occasions, a few patients experience side effects from the contrast material. These may include nausea, headache, and pain at the site of injection. It is very rare that patients experience hives, itchy eyes, or other allergic reactions to the contrast material. If you have allergic symptoms, tell the technologist. A radiologist or other doctor will be available for immediate assistance.

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Who interprets the results and how do I get them?

A radiologist, a doctor trained to supervise and interpret radiology exams, will analyze the images. The radiologist will send a signed report to your primary care or referring physician, who will share the results with you.

You may need a follow-up exam. If so, your doctor will explain why. Sometimes a follow-up exam further evaluates a potential issue with more views or a special imaging technique. It may also see if there has been any change in an issue over time. Follow-up exams are often the best way to see if treatment is working or if a problem needs attention.

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What are the benefits vs. risks?

Benefits

  • MRI is a noninvasive imaging technique that does not involve exposure to radiation.
  • MRI can help physicians evaluate the structures of the brain and can also provide functional information (fMRI) in selected cases.
  • MR images of the brain and other cranial structures are clearer and more detailed than with other imaging methods. This detail makes MRI an invaluable tool in early diagnosis and evaluation of many conditions, including tumors.
  • MRI can detect abnormalities that might be obscured by bone with other imaging methods.
  • The MRI gadolinium contrast material is less likely to cause an allergic reaction than the iodine-based contrast materials used for x-rays and CT scanning.
  • A variant called MR angiography (MRA) provides detailed images of blood vessels in the brain—often without the need for contrast material. See the MRA page for more information.
  • MRI can detect stroke at a very early stage by mapping the motion of water molecules in the tissue. This water motion, known as diffusion, is impaired by most strokes, often within less than 30 minutes from the onset of symptoms.

Risks

  • The MRI exam poses almost no risk to the average patient when appropriate safety guidelines are followed.
  • If sedation is used, there is a risk of using too much. However, your vital signs will be monitored to minimize this risk.
  • The strong magnetic field is not harmful to you. However, it may cause implanted medical devices to malfunction or distort the images.
  • Nephrogenic systemic fibrosis is a recognized complication related to injection of gadolinium contrast. It is exceptionally rare with the use of newer gadolinium contrast agents. It usually occurs in patients with serious kidney disease. Your doctor will carefully assess your kidney function before considering a contrast injection.
  • There is a very slight risk of an allergic reaction if your exam uses contrast material. Such reactions are usually mild and controlled by medication. If you have an allergic reaction, a doctor will be available for immediate assistance.
  • Although there are no known health effects, evidence has shown that very small amounts of gadolinium can remain in the body, particularly the brain, after multiple MRI exams. This is most likely to occur in patients receiving multiple MRI exams over their lifetime for monitoring chronic or high-risk health conditions. The contrast agent is mostly eliminated from the body through the kidneys. If you are a patient in this category, consult with your doctor about the possibility of gadolinium retention, as this effect varies from patient to patient.
  • IV contrast manufacturers indicate mothers should not breastfeed their babies for 24-48 hours after contrast material is given. However, the most recent American College of Radiology (ACR) Manual on Contrast Media reports that studies show the amount of contrast absorbed by the infant during breastfeeding is extremely low. For further information please consult the ACR Manual on Contrast Media and its references.

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What are the limitations of MRI of the Head?

High-quality images depend on your ability to remain perfectly still and follow breath-holding instructions while the images are being recorded. If you are anxious, confused or in severe pain, you may find it difficult to lie still during imaging.

A person who is very large may not fit into certain types of MRI machines. There are weight limits on the scanners.

Implants and other metallic objects can make it difficult to obtain clear images. Patient movement can have the same effect.

A very irregular heartbeat may affect the quality of images. This is because some techniques time the imaging based on the electrical activity of the heart.

MRI is generally not recommended for seriously injured patients. However, this decision is based on clinical judgment. This is because traction devices and life support equipment may distort the MR images. As a result, they must be kept away from the area to be imaged. Some trauma patients, however, may need MRI.

Present data show no convincing evidence that non contrast MRI harms the fetus of a pregnant woman. However, if the need for the exam is not time sensitive your doctor may delay the exam until after delivery. MRI gadolinium contrast agents are generally avoided during pregnancy except in very specific circumstances. Your doctor will discuss the benefits and risks of any MRI procedure with you. Doctors may perform MRI after the first trimester to assess the fetus for findings that are not fully evaluated by ultrasound.

MRI may not always distinguish between cancer tissue and fluid, known as edema.

An MRI exam typically costs more and may take more time than other imaging exams. Talk to your insurance provider if you have concerns about the cost of MRI.

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Which test, procedure or treatment is best for me?

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This page was reviewed on February, 08, 2021

MRI – Mayo Clinic

A cardiac MRI provides still or moving pictures of how the blood is flowing through the heart.

Vivien Williams: One out of four, that’s how many people will die of a heart related problem. Doctors at Mayo Clinic are trying to improve those statistics. They’re using MRIs to look inside the heart to find disease and tailor treatment to keep people healthier longer.

MRI technician: You can breathe. Breathe normal.

Vivien Williams: Magnetic Resonance Imaging, or MRI, allows doctors to look inside the heart as it beats.

Brian Shapiro, M.D., Mayo Clinic cardiologist: You can see here, this is the left ventricle, which is the main pumping chamber that pushes blood out of the body.

Vivien Williams: Dr. Brian Shapiro uses MRI to look for abnormalities in the heart.

Brian Shapiro, M.D.: What the MRI does is it looks at the tissue characteristics of the heart. So, swelling of the heart is a very common thing in heart attacks, and infections, and things like that.

Vivien Williams: The moving or still images show exactly where damage happens.

Brian Shapiro, M.D.: You would see it as a very bright, bright spot in the heart.

Vivien Williams: In addition to damage from heart attack or infection, MRI can also show Dr. Shapiro how well the heart pumps, where irregular heart beats originate, the location of blood clots, artery blockages, scar tissue, or even tumors. Because MRI allows doctors to see more detail of the heart, they can make more accurate diagnoses, and therefore tailor treatment for patients.

Brian Shapiro, M.D.: As you can actually show where the heart attack is, and the extent of the heart attack.

Vivien Williams: Images that tell Dr. Shapiro if a patient will recover, if there’s permanent damage, and what treatments might be best. Information from inside the heart that can help Dr. Shapiro and his colleagues better help their patients. Dr. Shapiro says while MRI can show lots of information about the heart, it does not replace other tests such as stress tests or echo cardiograms. It’s another option for looking inside the heart. For Medical Edge, I’m Vivien Williams.

90,000 What is MRI with contrast? Magnetic resonance imaging: contraindications, indications

What is MRI?

Magnetic resonance imaging is considered a safe research method, since it does not have radiation or ionizing radiation on the patient, therefore it is harmless to the body. MRI is prescribed for both adults and young children. As the name implies, this diagnostic method is based on the phenomenon of nuclear magnetic resonance.

To understand what an MRI is, you need to have an idea of ​​how it works. The essence of the technique is that the nuclei of some atoms, placed in a magnetic field, can absorb electromagnetic pulses. Subsequently, they convert energy into radio signals and, at the end of the pulse, emit them. Oscillations can be registered by special devices.

Tomographs used in medicine operate on the nuclei of hydrogen atoms that are part of water molecules, of which 70% of the human body consists.The amount of fluid in different organs of the body is different, as a result of which different signals are emitted during the scanning process. Thanks to this, the MRI machine can accurately:

  • visualize internal organs;
  • to distinguish healthy cells from pathological ones;
  • identify any organ dysfunction.

This is a unique diagnostic method that allows specialists to obtain high-quality images of almost all structures of the human body.An MRI study visualizes soft tissues, joints, and cartilage especially accurately and in detail. The innovative technique enables doctors to make images of structures that are difficult to obtain with other research methods. Such hard-to-reach tissues include those that are located near bone structures, for example:

  • intervertebral discs;
  • spinal cord and brain;
  • inner ear;
  • pelvic organs;
  • ligamentous apparatus.

However, the images of structures containing a small amount of water are less accurate in images. Therefore, magnetic resonance imaging is rarely used to examine the lungs or bones of the skeleton.

Study with contrast

In order to obtain clearer images during the study, the patient is prescribed a special substance before starting the procedure. This diagnostic method is called MRI with contrast. Many people wonder if this remedy can be dangerous for them.Such doubts are absolutely groundless, since the contrast is just a dye that allows you to highlight and better visualize the structures of the body. Its use does not pose any threat to the patient’s health, since the remedy:

  • has no contraindications;
  • is rapidly excreted from the body;
  • does not cause allergic reactions.

There were isolated cases of side effects: a small rash on the skin, headaches and light dizziness.According to medical statistics, such complications are observed only in 0.1% of cases and are associated with individual drug intolerance. Side effects are extremely rare and pass quickly.

There are several types of contrast media used in MRI with contrast. They differ in composition and method of application. Most often, patients are prescribed contrast, which is injected intravenously. This substance contains iron oxide, which helps to obtain the most accurate picture of blood vessels.Such a contrast is prescribed, for example, for the diagnosis of multiple sclerosis.

For a detailed diagnosis of the gastrointestinal tract of the patient, oral contrast agents are used. Such agents may be based on compounds of manganese and gadolinium soda. But the drug is made not only on the basis of such chemicals. Also, the simplest and most familiar products for each person, for example, green or blueberry tea, can be used as a contrast in MRI.They are effective because they contain a high concentration of manganese.

Today, almost 20% of all magnetic resonance imaging is performed using contrast media. The need for its use is determined by the doctor. Most often, the use of contrast is prescribed for suspected oncological diseases, pathology of the digestive tract, the study of the brain, as well as for diseases of the spine.

Contraindications

Patients who have repeatedly undergone such an examination and know what an MRI is, have experienced its effectiveness.Tomography is absolutely harmless, as it does not carry radiation and ionizing radiation. However, there are contraindications even for this diagnostic method. Since the operation of the tomograph is based on the influence of magnetic fields, people with:

are not allowed to undergo MRI

  • metal implants;
  • neurostimulators;
  • clips on vessels;
  • heart valves;
  • dental prostheses.

May not be allowed to examine patients with metal implants, intrauterine devices.The procedure is also strongly not recommended for women who use permanent eyeliner. Contraindication to MRI will be the presence in the patient’s body of fragments from bullet or other types of wounds.

People who suffer from mental illness and claustrophobia can refuse to undergo the examination. If there is a fear of a closed space, a person will be recommended to be examined on an open-type apparatus. The images obtained on such a tomograph may not be as detailed and accurate as on a closed one, but this will allow the patient to avoid an attack.

Some diseases in the stage of decompensation can interfere with the examination of a person. Refusal can be given to a patient who suffers from:

  • bronchial asthma;
  • diseases of the cardiovascular system;
  • severe dehydration.

Taking certain medicinal substances containing beta-blockers is an additional contraindication for MRI. People under the influence of alcohol or drugs are also not allowed to undergo the study.A patient with impaired or complete cessation of renal excretory function can also refuse if he was sent to undergo magnetic resonance imaging using a contrast agent.

Experts also identify relative contraindications for MRI, which cause controversy among physicians. It is not recommended to perform tomography for pregnant women during gestation up to 12 weeks. Although the studies did not reveal any threat to the intrauterine development of the fetus, the procedure is still not carried out.At this stage of pregnancy, the baby undergoes the main processes of the formation of internal organs and body systems, therefore, medical workers do not want to risk it. During this period, a woman is offered to use other modern research methods for making a diagnosis.

Indications for MRI diagnostics

Like any other examination method, magnetic resonance imaging has both strengths and weaknesses, which are quite numerous. In the study of some tissues, it gives the most accurate information, and when scanning others – less detailed.During the use of MRI, specialists have compiled a list of pathologies that are recommended for diagnosis using this method.

First of all, the examination helps to detect a large number of brain disorders . Specialists identify the following indications for MRI:

  • recurrent fainting;
  • Frequent dizziness;
  • traumatic brain injury;
  • convulsive seizures;
  • decreased sensitivity of the facial nerves.

The examination enables doctors to quickly detect metastases, diagnose any inflammatory diseases. The study is assigned not only to identify the disease, but also to determine the possibility of its surgical treatment. Immediately after therapy, patients are often asked to undergo a second MRI, the results of which will tell you how effective the prescribed treatment was and whether there is a risk of relapse.

Magnetic resonance imaging is very often prescribed to people to study the condition of the spine and the spinal cord .The survey helps:

  • Determine congenital and acquired developmental anomalies of the vertebrae.
  • To identify such diseases as: osteochondrosis, intervertebral hernias, radiculitis, arthrosis of the intervertebral joints, protrusion of discs , etc.
  • Assess the condition of the spinal cord and diagnose a pinched cord.
  • Determine the decrease in the height of the intervertebral discs.
  • Determine the presence and location of tumor formations.
  • Assess the degree of degenerative changes in the spine.

In this regard, the study allows you to accurately diagnose the following pathologies: protrusion and herniation of intervertebral discs, osteochondrosis, osteoporosis, spinal cord injuries.

Good results are obtained by MRI in the study of internal organs :

  • abdominal and retroperitoneal space: kidney, liver, pancreas, bile, adrenal glands, spleen;
  • small pelvis in women and men: ovaries, uterus, scrotum, bladder, prostate, penis, vas deferens, fallopian tubes;
  • chest cavity: lungs, thyroid and parathyroid glands;
  • nasopharynx: nasal sinuses, maxillary sinuses, pharynx, larynx, soft tissues of the neck.

Preparation for examination

The undoubted advantage of magnetic resonance imaging is the lack of special preparation for its passage, unlike many other diagnostic methods. The patient does not need to follow strict diets, refuse to eat before the examination, or in any other way change his usual rhythm of life.

Preparation for MRI is quite simple, and is mainly associated with the study of the patient’s medical history by the doctor. Before the examination, the specialist must receive comprehensive information about the patient’s health condition, therefore he:

  • conducts a survey;
  • clarifies all the transferred pathologies;
  • examines the results of previous procedures.

This is necessary in order to prevent errors during scanning and analysis of the received images. The doctor will definitely tell the patient how the study will be conducted and whether preparation for an MRI is necessary. Women who are scheduled for examination should remember that it is better not to apply makeup before the procedure, since cosmetics may contain metal microparticles. Such substances can cause distortion of the analysis results.

Immediately before the start of the procedure, the patient will be asked to remove all metal objects, including earrings, belts, rings, hairpins, clothes with zippers.The patient will be provided with a special gown that he will have to wear. The patient can also take comfortable light clothing with him, in which he will undergo the examination.

If a person is scheduled for an examination of the abdominal organs, then he may need special training before conducting an MRI. The patient will be advised not to eat or drink 5 hours before the scan. Patients who need to examine the condition of the pelvic organs are asked to drink a liter of clean water an hour before the examination.This will improve the quality and accuracy of the resulting images. It is important to remember that such a study is not recommended for women during menstruation.

Before starting the examination of the spinal column, patients do not need to perform any preparatory actions. However, you need to know that throughout the entire scan you will have to maintain complete immobility. This can be difficult for some patients with spinal problems, as they may experience severe discomfort.Patients with similar problems may be prescribed pain medications before the procedure.

What does an MRI show?

The examination is considered the most effective for detecting brain diseases . After studying a layer-by-layer image of tissues, it is not difficult for a doctor to find:

  • vasculitis;
  • increased intracranial pressure;
  • 90,011 stroke;

  • aneurysm;
  • cerebral infarction;
  • neoplasms.

The study allows you to find any inflammatory processes, to detect tumors, cysts, hematomas, ischemic zones. When examining the results of the study, the doctor may also identify some ophthalmic diseases. For example, MRI diagnostics is effective in detecting inflammatory processes in the structure of the eye, metastases that have penetrated the tissues of the organs of vision, thrombosis and optic nerve injuries.

Examination of the abdominal organs includes the study of the spleen, gallbladder and ducts, pancreas, kidneys and adrenal glands.During the procedure, doctors can detect the following diseases of internal organs :

  • pancreatitis;
  • cirrhosis of the liver;
  • benign and malignant formations;
  • cysts;
  • liver abscess;
  • cholecystitis.

When examining the kidneys and adrenal glands, doctors are able to identify any violations of their work, as well as study the state of the urinary tract. Even minor abnormalities are clearly visible on the images that are obtained during the MRI diagnosis.

Study of the pelvic organs in men reveals prostatitis, vesiculitis, proctitis, prostatic hypertrophy, teratomas. Pelvic examination can reveal in women :

  • endometriosis;
  • uterine fibroids;
  • adnexitis;
  • cysts;
  • 90,011 polyps;

  • cancerous tumors.

Magnetic resonance imaging is considered the most accurate method for diagnosing liver neoplasms. This study is called MR-pancreatocholangiography.It is performed without the use of a contrast agent, it helps to study all the bile ducts and identify a tumor even at the initial stage of its development.

Of all the methods for studying the state of the spine, MRI is considered the most accurate and informative. In the pictures, the specialist clearly sees the soft fibers that are located near the spine, all the nerve endings and blood vessels. This gives him the opportunity to study all the processes taking place in this area. MRI diagnostics of the back reveals:

  • displacement of bone structures;
  • rheumatoid arthritis;
  • narrowing of the spinal canal;
  • curvature of the spine;
  • ankylosing spondylitis.

In addition, MRI helps to identify any violations of the state of blood vessels and problems with blood circulation. Any infectious tissue lesions are also easily detected by examining the scan results.

How is the study going?

The duration of the magnetic resonance imaging can vary. Typically, the study takes 20 to 60 minutes. The duration of the procedure is affected by:

  • scope of research;
  • 90,011 the number of pathologies and their prevalence;

  • the need for a contrast agent.

Before starting the study, the patient must inform the doctor if he has contraindications to MRI. For example, if a woman suspects her pregnancy, then she needs to tell a specialist about this. The doctor may refuse to scan or replace it with a less risky one.

Many patients who are assigned to the study are interested in how the MRI goes. A person is laid on a special couch, fixing his legs, head and arms with special soft straps.This is to prevent any involuntary movement during the scan. Even a slight change in the patient’s posture threatens the appearance of inaccuracies and blurring of the image in the images.

Throughout the entire study, it is necessary to lie absolutely still. For children, this requirement is often impracticable. Therefore, if MRI is prescribed for a child , then before the procedure, he may be sedated or injected into the lungs of anesthesia. When the patient is nervous before the procedure, doctors may advise him to take a sedative.

The patient’s table is slowly moved into the tomograph. The device is a large, hollow cylinder. Since the tomograph makes rather sharp and loud sounds during operation, the patient will be offered to use earplugs or headphones, in which calm music will play.

The results of an MRI scan will be ready a few hours after the scan is completed. Pictures are sent to the attending physician or given to the patient in the arms. Since the procedure does not carry absolutely any harm to health, it can be repeated many times.

90,000 method description, radiation level, contraindications – MEDSI

Table of Contents

Magnetic resonance imaging (MRI) – what is it?

Magnetic resonance imaging is a modern method for studying the structure, condition and function of internal organs. The operation of the MRI device is based on the phenomenon of resonance of magnetic fields and on the different display of tissues of different structures as a result. The signals are transmitted to a computer, which decrypts them and converts them into an image.The obtained data is analyzed and evaluated by a specialist – a radiologist.

Modern equipment allows to obtain an image of internal organs, due to which the study has a high information content. MRI can help identify a large number of diseases that are not diagnosed as accurately with other methods.

MRI has great advantages over invasive and radiographic research methods, as it is a safe and comfortable procedure.Thanks to this, the study is used in the diagnosis of diseases of many organs and systems:

  • brain
  • cerebral vessels
  • temporomandibular joint
  • joints
  • spinal cord
  • spine
  • abdominal organs
  • Pelvis
  • reproductive system,
  • hearts

One of the most common areas of application of magnetic resonance imaging is the diagnosis of diseases of the nervous system.MRI of the brain allows you to identify tumors and determine the stage of their development, diagnose problems with blood vessels, multiple sclerosis and other pathologies.

Many patients are interested in what dose of radiation the body receives during the study, whether MRI is dangerous to health.

MRI radiation level

Unlike X-rays and computed tomography (CT), patients receive a zero dose of radiation during an MRI, since this study is not based on ionizing radiation, but on magnetic effects.

The effect of a magnetic resonance imaging scanner is comparable to that of a cell phone or microwave oven. MRI does not cause disturbances in the structure, condition and function of tissues and organs, being at the same time a highly accurate diagnostic method.

Therefore, you can be sure: no radiation occurs with MRI.

Magnetic resonance imaging for oncopathology

The absence of radiation makes it possible to use MRI for cancer patients with confirmed diagnoses of various malignant tumors for whom X-ray methods of investigation are contraindicated.Due to ionizing radiation, X-rays and computed tomography can harm the tissues of the body: cause changes in DNA and negatively affect already existing pathological processes. The electromagnetic effect during MRI is safe for both tumors and healthy tissues and organs.

For patients with oncopathology, MRI is prescribed with the use of a contrast agent to increase the information content of the study, this allows a detailed study of the tumor and the vascular network that feeds it.

How often can an MRI scan be done?

In the absence of contraindications, MRI can be prescribed (depending on the disease and the characteristics of its course) as often as necessary to develop an effective treatment plan or adjust it. Since the procedure is safe for the body, it can be carried out with minimal time intervals.

The frequency of an MRI scan can only be determined by a doctor. In the presence of an urgent need or in accordance with the developed plan of dynamic observation, the study is carried out several times during one day.MRI is not a health hazard.

Tomography – Principle of Operation

The subject lies down on a sliding table, which slowly passes inside the magnet tunnel. A magnetic field is created in it, which acts on the hydrogen atoms in the patient’s body, forcing them to line up parallel to the emerging field. The radiofrequency pulse emitted by the tomograph causes a resonance in the hydrogen atoms. This “feedback” is registered by the computer, which converts the response vibrations into an image.This principle of operation of the tomograph is called nuclear magnetic resonance.

MRI is performed within 15–20 minutes, during which time the computer analyzes a sufficient amount of information obtained as a result of the interaction of the magnetic fields of the tomograph and the patient’s body.

During the MRI, the patient does not experience any discomfort. It is necessary to lie still, since the quality of the images obtained and the accuracy of the diagnosis depend on this.

In order not to disrupt the operation of the tomograph, based on electromagnetic resonance, all metal objects and electronic accessories and devices must be removed before the examination.Clothes should be free of metal parts.

No preliminary preparation for MRI is required.

Contraindications

MRI, being a safe and painless diagnostic method, has a number of contraindications, which are associated not only with the alleged negative influence of electromagnetic waves, but also with a psychological factor, and with cases of individual reactions to contrast agents.

MRI is contraindicated:

  • during pregnancy in the first trimester (due to possible negative effects of electromagnetic waves on the fetus)
  • 90,011 patients with metal implants (pacemakers, hearing aids, vascular clips, joint prostheses, etc.))

    90 011 patients with allergic reactions

    90 011 patients suffering from claustrophobia and other mental disorders

Are complications possible?

Numerous studies on MRI have not revealed any negative consequences of this diagnostic procedure for the body. The effect of electromagnetic waves emitted by a tomograph is comparable to that of a cell phone. We are under the influence of the latter for a much longer time.

Therefore, it is safe to say that there are no side effects during the study.

Advantages of MRI at MEDSI

  • Equipment of world manufacturers
  • Transcript of examinations by experienced radiologists
  • Conducting research for adults and children
  • Conducting research under sedation (in a state of drug sleep) for patients suffering from claustrophobia
  • Security

Contraindications to MRI full list with examples

Implants and pacemakers
MRI for tattoos and permanent make-up
MRI for pregnancy, lactation and for infants
MRI with contrast contraindications
MRI for true and false claustrophobia
Diseases for which MRI is contraindicated
Drug compatibility
Drug compatibility
to MRI, CT, ultrasound, PET

Magnetic resonance imaging is safe for almost everyone, does not harm the body even with frequent use, and the current conditional and absolute contraindications are systematized in this article.

Implants and pacemakers

The main limitation when using MRI is its main physical property – magnetism. There are no organs in the human body for which a short-term exposure to a strong magnetic field would be dangerous. However, the implantation of ferromagnetic metal devices, a pacemaker, or other magnetically sensitive objects can be hazardous to both the wearer and the correct operation of the built-in equipment.

With the accumulation of experience in MRI studies, the number of contraindications to magnetic resonance imaging decreases. In addition, materials for the manufacture of implants, stimulators and other electronic devices introduced into the human body are constantly being improved. This allows them to avoid malfunctions and damage even in a powerful electromagnetic field.

In each doubtful case, the correct decision would be to consult with the radiologist who provides diagnostics on a specific device, collecting as much information as possible about the subject that may interfere with the MRI examination.It should be noted that in these situations, 3-Tesla devices are considered conditionally more dangerous than 1.5-Tesla ones.

Such items can be artificial joints, shrapnel and bullets, metal plates used in the treatment of bone fractures and correction of the spine, prostheses, pacemakers, swallowed items with magnetic properties.

MRI with tattoos and permanent makeup

Sometimes permanent makeup and tattoos can contain iron compounds and also react to a powerful electromagnetic field.When the emitter is activated, all metal objects begin to move and heat up, which can cause discomfort or even damage to the skin.

This is not very dangerous, but if unpleasant sensations appear during the examination or placement, you must immediately notify the staff conducting the session about this by pressing the special alarm pneumatic button, which is in the patient’s hand while in the MR-tomograph.

MRI during pregnancy, lactation and for babies

The conditional limitation is pregnancy in the first trimester, up to 12 weeks of gestation.Although no obvious adverse effects from MRI on the fetus have been identified, scientists doubt that they have already collected enough knowledge about the effects of strong electromagnetic radiation in the early period of pregnancy. This doubt gave rise to the generally accepted rule: in the first 90 days, nothing should affect the development of the embryo, including the electromagnetic field.

In addition, the use of contrast agents, which are often required for MRI, are limited in nursing and pregnant women. The limitations regarding MRI in infants and young children are near-medical.There are no direct medical contraindications, but one of the prerequisites for the study is prolonged immobility, which the baby cannot withstand, and the noise of the apparatus will not allow the examination in a dream. Thus, MRI examinations are carried out only in children who are able to assist the doctor in carrying out the procedure. As a rule, we are talking about the age of over 5-7 years.

In some cases, when alternative methods of research in children do not provide a sufficient quality of diagnosis, they resort to conducting an MRI study under sedation or anesthesia.

From the above, another limitation is formed: they try not to do MRI for children and adults suffering from hyperkinesis.

Contraindications to MRI with contrast

There are no contraindications to MRI with contrast, although there are some limitations. Gadolinium-based contrast agents are safe for the human body, since the active substance is chemically neutralized by a chelate lattice, which is described in detail in the article on our site MRI with contrast, and is clearly shown in a video shot specially for our site.This 3-minute video can also be viewed on the contrast media page or on our MRI YouTube channel.

In some rare cases, there are allergic reactions to contrast agents, this is less than 0.1% of the total number of studies with contrast. If they were identified earlier during MRI, this may serve as a relative contraindication to their use.

Limitations when using MRI with contrast

For pregnant women, as well as during breastfeeding, MRI with contrast should be performed only for special indications.List of other relative contraindications:

  • susceptibility to allergic reactions;
  • bronchial asthma in the acute stage;
  • very severe dehydration;
  • severe decompensated kidney disease.

MRI for true and false claustrophobia

Another common syndrome is becoming a contraindication to MRI; about 5% of people suffer from it – this is true claustrophobia.People suffering from it cannot be in a conventionally limited space, they have an unaccountable uncontrollable fear, which leads to overexcitation. It is almost impossible to withstand it. Of course, in such cases, the procedure is immediately terminated.

However, claustrophobia cannot be considered an absolute contraindication. There are several effective ways to neutralize your fear of confined spaces. In addition, most cases of claustrophobia are relative, not accompanied by a panic attack, but cause significant discomfort, which must also be dealt with.This claustrophobia is called false, and it can be overcome in the following ways.

Most often it turns out to be enough to create in the subject a feeling that the space is not closed by moving or removing some of the equipment elements that obstruct visibility. Some people are helped by turning on the music in the headphones or removing the protective noise cancellers. In some models, a mirror is installed, allowing you to see the space behind or in front of the MRI machine, which allows you to cope even with attacks of true claustrophobia.

Sometimes the presence of an accompanying loved one helps out, who can sit next to him during the research. This is not forbidden.

In some cases, we recommend the use of mild sedatives. If none of the methods available in the conditions of our diagnostic center gives an effect, MRI is canceled, payment for it is not charged, and the patient is offered to undergo an examination on an open-type tomograph.

Still worth a try, given the fact that these machines do not provide such high resolution images as closed-type tomographs.Therefore, in some cases, an MRI study is still performed under anesthesia on closed high-field tomographs.

How does a working MRI device sound like

Most often, the examinee hears quite loud sounds alternating depending on the examination programs used. To get an idea of ​​the nature of this sound, we recorded it and posted it here.

The audio tag is not supported by your browser. Download music. The audio tag is not supported by your browser. Download music.

Diseases for which MRI is contraindicated

The list of diseases in which magnetic resonance imaging is limited is extremely small. It is dictated by the conditions and physical factors of MRI.

The first on this list are mental and neurological diseases that will not allow a person to withstand the period of immobility required for research. And this is 20-30 minutes.

Sometimes the immobility is interfered with by pain caused by the investigational or concomitant disease.For example, knee pain may interfere with lying still. In such cases, our doctors resort to pain relief in the most harmless and effective way, based on the nature of the disease.

There is also a short list of diseases in which the decision on the possibility of conducting an MRI examination will be made depending on the severity and decompensation of physiological functions. It is:

  • an attack of bronchial asthma ;
  • very high blood creatinine ;
  • State severe dehydration, exhaustion and impaired renal excretory function;
  • State strong intoxication, including narcotic, which does not allow immobility;
  • cardiovascular diseases in the stage of decompensation ;
  • excessive weight, for which the stacking table is not designed.

In the latter case, the limitation is due to the fact that each tomograph is designed for a certain maximum patient weight, most often it is no more than 110 kg. There are devices that allow you to take a load of up to 200 kg.

The issues of conducting an MRI study in severe exhaustion, dehydration and other decompensated conditions are resolved ONLY in a hospital where an intensive care unit operates. This is due to the threat of a violation of vital functions during the study, an increase in body temperature in such patients and the danger of a sharp deterioration in the condition.Standard MRI does not have an intensive care unit and we will refuse to conduct an MRI scan in our Center for such patients.

MRI Compatibility with Medication

Usually, taking medications is not an obstacle to the procedure, but, in rare cases, if the patient’s condition inspires fear in the doctor in view of the instability of the functioning of vital organs – the heart or the brain, he has the right to postpone the study.

In case of doubt, it is best to consult with a competent specialist or make an appointment and get a preliminary consultation with a doctor in our center.

Comparison of the main contraindications by type of radiation diagnostics

Type of contraindication MRI CT Ultrasound PET
Pregnancy Except first trimester Not allowed Allowed Not allowed
Body weight Standard up to 130 kg, on special tray up to 201 kg Standard up to 130 kg, on special tray up to 201 kg Doesn’t matter Standard up to 130 kg, on special tray up to 201 kg
Early postoperative period Allowed Sometimes preferred, fabric dependent Doesn’t matter Not effective
Inflammatory process Allowed Allowed Allowed Undesirable – Risk of false positives
Contrast allergy occurs Rarely Often No Rarely, for iodine containing contrast – often
Implants, pacemaker Lying.implants are tested for compatibility with MRI 1.5 T Allowed Allowed Allowed
False claustrophobia Allowed by preparation Rarely Not found Rarely
True claustrophobia Acceptable when sedated Rarely Not found Rarely
Cachexia (extreme wasting) Allowed by preparation Allowed by preparation Allowed Allowed by preparation
Hyperkinesis Acceptable when sedated Acceptable when sedated Allowed Acceptable when sedated
Renal failure Preferred Extremely careful Allowed Extremely careful
Small children Preferred for sedation Extremely careful Preferred Extremely careful

In all cases of doubts or questions about contraindications to MRI, you can call our polite qualified administrators and get preliminary advice on troubling issues and make an appointment with a doctor’s consultation and / or MRI diagnostics.You can also order a call at a convenient time or ask a question through the feedback form. Our phone number is +7 812 600-13-51.

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How is MRI with contrast performed, side effects and contraindications

Depending on the area of ​​the body being examined, the doctor may order a contrast-enhanced MRI. Before the examination with contrast, a special substance is injected into the patient’s body – a contrast, which improves the visualization of the organ or system under study and contributes to the most accurate diagnosis.High diagnostic accuracy is a guarantee of adequate treatment with a stable therapeutic effect.

Magnetic resonance imaging with contrasting is based on the ability of the blood flow to carry intravenous drugs throughout the body and accumulate them in places with a developed network of medium and small blood vessels. This method examines blood vessels, reveals neoplasms that are characterized by hypertrophied blood supply, and other pathologies.

Composition of contrast medium

MRI contrast agent contains gadolinium. Unlike iodine, which is a substance for contrast-enhanced computed tomography, gadolinium is not an allergen. Small doses, which are administered for high-precision examination, are absolutely safe and are completely excreted from the patient’s body through the urinary system within 24 hours.

How is MRI with contrast performed

The MRI procedure with a contrast agent includes several stages:

  • preparatory period to eliminate side effects, about which the doctor advises the patient in advance;
  • intravenous administration of a substance through a catheter;
  • examination within 15-20 minutes.

At the end of the procedure, the patient can immediately go home and lead a normal life. An exception may be people suffering from allergic diseases and kidney pathologies, who may develop adverse reactions to the composition of a particular contrast agent or the process of its removal from the body. To avoid this situation, you should undergo some preparation before the examination.

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How to eliminate the side effects of MRI with contrast

Despite the fact that side effects of the substance are extremely rare, it is necessary to undergo preliminary preparation for the procedure, which may include:

  • consultation of an allergist in the presence of allergic and autoimmune diseases;
  • clinical analysis of blood and urine;
  • tests for the identification of an allergic agent.

A few hours before the procedure, food should be avoided to prevent side effects such as nausea and vomiting after administration of gadolinium.

Contraindications for MRI with contrast

The list of contraindications for the use of contrast in magnetic resonance imaging includes general absolute and relative limitations that do not recommend conducting MRI in certain categories of patients: pregnant women, with the presence of electronic or metal implants, suffering from mental disorders, etc.

The main contraindication limiting contrast enhancement is the patient’s allergic reaction to the contrast used. Contrasting is also not performed in severe forms of renal dysfunction.

If the subject has a breastfed baby, feeding should be excluded for the period of complete elimination of gadolinium from the body.

MRI contrast – MRI Sevastopol

Contrast tomography

MRI or magnetic resonance imaging is the newest way to diagnose diseases of internal organs and systems.The study allows you to assess the thickness, texture, position and size of any organ. To obtain the most informative result, contrast MRI is prescribed in Crimea .

Service name
Cost Examination time, min
Intravenous contrasting (10 ml.) RUB 3,000 +25
Intravenous contrasting (15 ml.) 3 500 rub +25
Intravenous contrasting (20 ml.) RUB 4,000 +25

What does contrast give?

Contrast is used by physicians to obtain a more detailed image. The reasons for this particular type of research are:

• precise definition of the boundaries of organs or tumors.
• diagnostics of the inflammatory process not detected by other methods.
• suspicion of structural changes in tissues;
• diagnostics of vascular pathologies;
• tomography of the brain, both before and after treatment;
• detection of diseases of the spine;
• study of the digestive system, especially the stomach and intestines.

MRI with contrast provides comprehensive information about the state of any organ.

Contrast agents

MRI contrast can be administered in two different ways.Intravascular and oral dyes are released accordingly. The first option is shown in the diagnosis of blood vessel pathologies. The most commonly used substances are iron oxide. They allow you to obtain contrasting images of blood vessels. Often, substances are used in the diagnosis of liver tumors. A manganese chelating agent can also be used for intravenous ascertaining.
During an MRI scan in Sevastopol with oral dye, in addition to chelating agents, food products are used, for example, green or blueberry tea.This is explained by the presence of a large amount of magnesium. When examining the digestive organs, perflubron is often used.
Side effects during MRI in Sevastopol are extremely rare. In exceptional cases, the development of kidney damage is likely, therefore, with renal and hepatic insufficiency, the choice of contrast is approached especially carefully.

Advantages

  • Security

    MRI studies have nothing to do with radiation and ionizing radiation – X-rays.

  • Multiple use

    MRI studies can be performed as long as you like without surgery.

  • Informative value

    MRI studies give a complete picture of organs, tissues, blood vessels, and bone structures of a person.

  • Accuracy

    MRI examinations are an accurate diagnosis in the early stages of the disease, which leads to the correct treatment.

Contraindications

  • Metal objects

    MRI cannot be performed if there is metal in the human body: braces, staples and clips in vessels, etc.d.

  • Claustrophobia

    Fear of confined spaces can harm humans. The patient does not give an account of his actions.

  • Pregnancy

    MRI is contraindicated in pregnant women of the 1st trimester, as well as with the introduction of contrast agents.

  • Implants and devices

    If present in the body: pacemaker, insulin pumps, neurostimulants, etc.d.

90,000 How does MRI differ from computed tomography

Rostov Regional Clinical Hospital is the only
medical institution in the Rostov region that today performs
magnetic resonance imaging of the heart.

In 2015, the Rostov Regional Clinical Hospital began examining patients on a new generation magnetic resonance imaging scanner. Olga Kucherenko, head of the X-ray diagnostic department of the Russian Regional Clinical Hospital, tells about the amazing possibilities of the novelty, as well as about how magnetic resonance imaging fundamentally differs – both in technical and diagnostic terms – from a computer one.

– Our new magnetic resonance imaging scanner is the latest American development that provides the most successful ratio of the detail of the study of the human body to the quality of the resulting image, as well as provides a lot of additional options for diagnosing the heart and blood vessels, oncological neoplasms, small joints and much more. …

For especially inquisitive patients, it is worth explaining in a nutshell that a magnetic resonance imaging scanner creates a constant magnetic field of high intensity and, with the help of electromagnetic waves, excites atomic nuclei in the human body, most often of hydrogen.There is an electromagnetic response of these nuclei – radio signals that are different in healthy and diseased cells. All that remains is to transform all the information received into an image. In this case, the initial characteristic that affects the quality of the study is the magnitude of the magnetic field of the tomograph – it is measured in teslas.

Today, medical practice shows that 1.5 Tesla – namely, such devices are installed in our hospital – is the optimal value of the magnetic field strength of the tomograph.For obvious reasons, less powerful tomographs – 0.8 Tesla – are still quite common in medical institutions, including in Rostov. Now in some clinics and outpatient clinics there are devices for 3 Tesla, but practice has shown that, along with some advantages, there are a number of limitations for their use. Therefore, most of the world’s clinics acquire 3-Tesla systems as second and third, performing various scientific research on them. In clinical diagnostics, 1.5 Tesla magnetic resonance imaging devices are still the leaders as they are optimal for all types of research.

– Are there any other technical features that directly affect the quality of the patient’s MRI examination?

– In fact, there are many of them, but to understand them, you need to be a specialist. For an ordinary patient, going for research, it is important to understand only one thing: what a particular device can and what not. For example, any magnetic resonance imager allows you to study many organs and systems of the human body, but the degree of detail and the quality of the image obtained during such a study depends on the complex of hardware and software capabilities of a particular device.

Radiologists receive and interpret information,
and a lot depends on their qualifications.

The fact is that each of the leading manufacturers in this area, based on the same technology, produces unique devices in their own way, constantly improving their various elements and expanding software capabilities – to improve existing functions and obtain new ones.

In our new tomograph, the technology of covering the whole body has been improved, it allows you to obtain more detailed and high-quality images of the heart, oncological neoplasms, miniature structures of the body, such as the cochlea of ​​the inner ear, small vessels or joints.Finally, it is faster, which significantly reduces the time for a standard examination – on average, up to 10-20 minutes. In practice, this means an increase in the number of admitted patients and a decrease in the cost of the study itself. By the way, work on the new tomograph is carried out in two shifts – until 20.00, which allows us to see patients both before the start of their working day and in the evening.

– It is now widely believed that MRI is the same CT, only better …

– This is an extremely simplified representation.Magnetic resonance imaging and spiral computed tomography, often referred to simply as CT, are not competitors. Yes, there are many organs and systems, the study of which is possible in both ways. And here the choice entirely depends on the attending physician, who, based on the results of the examination of the patient, stops at the option of the study that is able to give him all the missing information.

Of course, studies on a computed tomography scanner are cheaper and faster, but they are associated with radiation, because CT is, in fact, the same X-ray, only it has grown wiser.In a very short period of time, a computed tomography scanner scans the human body in the right place in different sections and generates a high quality digital image that can be viewed on a monitor and displayed on film.

Diagnosis of diseases of the bronchopulmonary system
is based solely on computed tomography.

A MRI does not give radiation exposure to the human body, and in general, until now, no side effects from its use have been identified.The procedure is completely painless, however, it is accompanied by a strong noise, therefore, we offer headphones to patients to reduce discomfort.

Further, computed tomography is simply ineffective in examining certain parts of the body, for example, joints, pelvic organs, intestines. At the same time, the diagnosis of diseases of the bronchopulmonary system is based solely on computed tomography. And in some cases, we provide the patient with computed tomography and magnetic resonance imaging, for example, if it is necessary to take a closer look at changes in bone structures and soft tissues or to clarify the prevalence of oncological neoplasms.

– Which CT scanner is better for examining the heart?

– By the way, the Rostov Regional Clinical Hospital is the only medical institution in Rostov that today conducts magnetic resonance imaging of the heart, and our cardiologists and surgeons experienced its exceptional capabilities for assessing the state of the myocardium or detecting microscopic tumor formations.

Here is a very recent case: a patient who has been treated for a long time at the place of residence for the consequences of a heart attack has turned to our Cardiac Surgery Center.Having achieved no improvement, they sent us to us, and it was the MRI of the heart that made it possible to quickly establish that he was suffering mainly from cardiomyopathy, and not from postinfarction cardiosclerosis. The doctors adjusted the treatment – and in a matter of days the patient felt much better.

And even in the case when the diagnosis is beyond doubt, for example, it is quite obvious that the patient needs surgical treatment to eliminate the consequences of myocardial infarction, MRI allows cardiac surgeons to accurately determine the scope of the operation and take into account various additional factors: the presence of a left ventricular aneurysm or , say, a blood clot in the heart cavity.

The degree of detail and quality of the image obtained as a result of the
magnetic resonance imaging study depends on the set of hardware
and software capabilities of a particular device.

Spiral computed tomography, especially ultrasound, is not able to cope with such a volume of tasks, although CT is much more informative than MRI if it is required to assess the state of the heart vessels. Therefore, we very rarely conduct MRI of coronary vessels and generally try to explain to those patients who want to sign up for the procedure on their own, without a doctor’s referral, that a full complex of heart examinations lasts up to one and a half hours, that is, it is desirable that a cardiologist or cardiovascular surgeon, prescribing MRI, if possible, narrowed the task of diagnosticians.

– You mentioned that there are contraindications to MRI …

– Yes, and there are a lot of them. Basically, they are associated with the physical features of the magnetic field, therefore, absolute contraindications include the presence in the patient’s body of metal foreign bodies, ferromagnetic implants, as well as devices whose operation may be impaired (for example, a pacemaker, an automatic dispenser of medicinal substances).

Also, MRI should not be performed on patients with an artificial anus with a magnetic seal or an artificial heart valve with metal elements.For steel implants, clamps / clips on vessels, artificial hip joints, elements of osteosynthesis, a certificate for the introduced material is required for making a decision. Metal teeth, tantalum braces on the sternum are acceptable, although this may reduce image quality. The question of conducting a study in the case of an artificial heart valve or a cava filter is decided after consultation with a specialist in the department.

Another group of contraindications is associated with the physical impossibility of carrying out the procedure if the patient, for example, weighs more than 150 kilograms.Many healthcare facilities cannot perform an MRI scan on a ventilated patient. This is possible in the Rostov Regional Clinical Hospital.

In both computed tomography and magnetic resonance imaging
,
intravenous contrast can be used.

Relative contraindications to magnetic resonance imaging are associated with the psychological characteristics of the patient – claustrophobia excludes MRI on a powerful machine, because the patient has to spend 10-20 minutes in a rather cramped space of a closed-type tomograph.

MRI is usually not prescribed in the first trimester of pregnancy. Difficulties also arise if the patient is unable to maintain immobility during the examination, which is necessary to obtain a high-quality image. For this reason, we usually do not do MRIs for children under the age of five, who are difficult to persuade to lie still for so long.

This is an incomplete list, which is why the registration for tomographic examinations at the RCCH is carried out not by a laboratory assistant, but by a radiologist, in order to further clarify the need for this or that type of examination, to identify all contraindications, and also, if necessary, to involve his colleagues in the procedure from the hospital.

After all, the main thing is the end result, which every patient strives for – to get rid of the disease. The device does not issue ready-made diagnoses and does not prescribe treatment. Radiologists receive and interpret information, and a lot depends on their qualifications, but it is the attending physician who makes the final diagnosis, determines the treatment regimen and is responsible for the result.

The Rostov Regional Clinical Hospital is able to provide the patient with a full range of high-quality medical services: competently conducting high-tech research and, if necessary, promptly engaging a clinician specializing in the required field of medicine in such a study, and then carrying out subsequent treatment, up to the most complex surgical operations, and postoperative rehabilitation.

Diagnostics of oncology using MRI

Detection of tumors using magnetic resonance imaging is a highly informative, safe, non-invasive method that is used in neurosurgery, oncology, and neurology. The number of studies is not limited – it can be used for the purpose of diagnostics, dynamic monitoring of tumor processes.

MRI diagnostics for tumor diseases

If cancer is suspected, patients are first referred for magnetic resonance imaging.This is due to the high level of detail of modern MRI machines and safety. The results of the study are reliable, the probability of a false positive diagnosis is less than 5%. In oncology, MRI is used in the following situations:

  • Suspected tumor formation;
  • Presence of precancerous conditions in which there is a high probability of cell degeneration into cancerous;
  • planning the volume or carrying out surgery;
  • control of results after surgical treatment;
  • Monitoring of neoplasm development – in case of inoperability, oncologists monitor the development of education in order to adjust treatment tactics.

MRI shows any tumors, difficulties arise when they are detected in the bone, lung tissue, where they are poorly visualized. In this case, CT of bones and lungs is shown.

Metastatic formations include tissues of affected organs that have entered the brain through the bloodstream. Sometimes they merge, turning into one large pathological focus. Based on the characteristics from the image, the doctor can guess where the malignant cells came from.

Differences between malignant and benign formations on MRI images

On the obtained MRI images, the changes depend on the histological characteristics of the neoplasm.Malignant ones are characterized by heterogeneity of the structure due to hemorrhage, necrotization, calcification, and infiltrative growth. Benign tumors are limited by the capsule and do not grow into the surrounding tissues, they only expand, pushing them away. Symptoms, as a rule, develop smoothly, with periods of exacerbation, remission. Signs of benign lesions:

  • smooth contours;
  • uniform color;
  • no dislocation, perifocal edema;
  • tumor evenly and weakly accumulates contrast agent.

Malignant formations are rapidly progressing, destroying healthy tissues, and have a low susceptibility to therapeutic treatment. Common signs in pictures:

  • Uneven contrast accumulation;
  • foci of hemorrhage;
  • displacement of the structures of the brain, even with a small size of the formation;
  • structure heterogeneity;
  • uneven contours.

After an MRI of the brain, histological verification is often required using a biopsy – taking a small piece of tissue from the desired area under the control of ultrasound, CT or MRI.

Can a tumor be detected by MRI without contrast?

It is sometimes difficult to recognize a small formation. With high magnetic field strengths, a native MRI scan can be done to obtain a high quality image, but contrasting makes the task much easier. With its help, tumors are detected at any stage, it is possible to carry out a differential diagnosis between a malignant and benign process.
Side effects of the administration of a contrast agent are extremely rare, in the absence of contraindications, this is a good way to detect malignant tumors.On MRI with contrast, it is possible to more accurately determine the degree of invasion into healthy tissues, volume, localization, blood supply to the formation, and individual characteristics. All these indicators are reflected in the planning of treatment tactics.
The percentage of congruence of the anatomical location of the lesions with magnetic resonance imaging is higher than with CT.

Contraindications to MRI diagnostics

The study is approved by cancer patients – it does not give radiation exposure, since it is not associated with X-rays.The magnetic field does not pose a danger to the body; you can be examined repeatedly. But despite the safety, there are contraindications:

  • Contrast-enhanced MRI is not done in case of allergy to contrast agent, severe kidney pathologies;
  • early pregnancy is a relative contraindication, for health reasons, the study is allowed at any time;
  • The presence of metal products in the body: cochlear implants, dentures, pacemakers, vascular clips, etc.d.

In the presence of relative contraindications, the doctor individually decides on the possibility of research. Takes into account the benefits of the examination results for the patient and the degree of possible health risks.

Conclusion of MRI in oncology

After the examination, the patient receives the results on an information carrier or on paper. Deciphering is done by a radiologist. It describes changes in the MR signal, dimensions, formation contours, and dislocation phenomena.The results of the study are not a diagnosis, they are studied by the specialist who sent them for diagnosis, or the oncologist. Tomography provides valuable information, but a definitive diagnosis of cancer can only be made after a biopsy.
Deciphering MRI of the brain in combination with clinical, laboratory, instrumental data helps to make an accurate diagnosis, choose a treatment tactics. It is not always possible to conduct a histological examination before surgery, often the diagnosis is confirmed after the removal of the tumor and sending it for a biopsy.

Research in oncological diseases in the diagnostic center “DonMed”

At the DonMed Medical Center you can undergo magnetic resonance imaging of any part of the body using the Philips Achieva 1.5T apparatus, which has a high scanning power. Its well thought-out design allows for examination of patients with a fear of a confined space due to the partially open tunnel of the tomograph.
For more details about the MRI service in the DonMed clinic, follow the link.
The clinic employs experienced, qualified doctors – neurologists, oncologists, gynecologists, radiologists and other specialists.The offices are equipped with modern equipment that meets international standards. We have affordable prices, promotions are provided. To pass urgent tests, undergo a study or consultation with doctors, fill out an application on the website or call us at the specified phone number.
DonMed Center offers complex diagnostics using the check-up program.