What are the potential effects of an MRI scan. How does an MRI work and what are the safety considerations. What happens during an MRI procedure and who can undergo this imaging test.

What is Magnetic Resonance Imaging (MRI)?

Magnetic Resonance Imaging, commonly known as MRI, is a sophisticated medical imaging technique that utilizes powerful magnets and radio waves to generate detailed images of the body’s internal structures. This non-invasive procedure allows healthcare professionals to examine various organs, tissues, and systems without the need for surgery or radiation exposure.

MRI scanners consist of a large, tube-shaped magnet that creates a strong magnetic field. The patient lies on a movable table that slides into the tube during the examination. The scanner’s magnetic field aligns the protons in the body’s water molecules, while radio waves are used to temporarily disrupt this alignment. As the protons realign, they emit radio signals that are detected by the scanner and processed by a computer to create highly detailed cross-sectional images.

Key Components of an MRI Scanner

• Large tube-shaped magnet
• Movable examination table
• Radio wave transmitter and receiver
• Computer system for image processing

How Does an MRI Scan Work?

The fundamental principle behind MRI technology lies in the behavior of hydrogen atoms within the body’s tissues. These atoms, particularly abundant in water molecules, act like tiny magnets when exposed to the scanner’s powerful magnetic field. The MRI process can be broken down into several steps:

1. Alignment: The strong magnetic field causes the protons in hydrogen atoms to align in a specific direction.
2. Excitation: Short bursts of radio waves are sent to targeted areas, causing the protons to temporarily move out of alignment.
3. Relaxation: When the radio waves are turned off, the protons return to their original aligned state, emitting radio signals in the process.
4. Detection: Sensitive receivers pick up these emitted radio signals.
5. Image Creation: A computer processes the detected signals to generate detailed cross-sectional images of the body.

The varying relaxation rates of protons in different tissues allow MRI to distinguish between various types of body structures, providing exceptional contrast and detail in the resulting images.

Applications of MRI in Medical Diagnostics

MRI scans have revolutionized medical imaging and diagnostics, offering unparalleled insights into the body’s internal structures. Their versatility and ability to provide high-resolution images make them invaluable in numerous medical applications.

Common Areas Examined by MRI

• Brain and spinal cord
• Bones and joints
• Breasts
• Heart and blood vessels
• Internal organs (liver, womb, prostate gland)

Healthcare providers utilize MRI scans for various purposes, including:

• Diagnosing complex medical conditions
• Planning treatment strategies
• Evaluating the effectiveness of previous treatments
• Monitoring disease progression
• Guiding surgical procedures

The MRI Procedure: What to Expect

Undergoing an MRI scan can be a unique experience for patients. Understanding the procedure can help alleviate any anxiety or concerns. Here’s what typically happens during an MRI examination:

1. Preparation: Patients are asked to remove metal objects and may be given a hospital gown to wear.
2. Positioning: The patient lies on a flat bed that moves into the scanner. Depending on the area being examined, entry may be head-first or feet-first.
3. Scanning: A radiographer operates the scanner from a separate room, communicating with the patient via an intercom system.
4. Duration: Scans typically last between 15 to 90 minutes, depending on the area being imaged and the number of scans required.
5. Noise: The scanner produces loud tapping noises during the procedure. Earplugs or headphones are provided for comfort.

It’s crucial for patients to remain as still as possible during the scan to ensure clear, accurate images. Some individuals may find the enclosed space of the scanner challenging, but radiographers are trained to provide support and guidance throughout the procedure.

Safety Considerations and Potential Risks of MRI

MRI is generally considered a safe and painless procedure. Unlike X-rays or CT scans, it does not use ionizing radiation, making it a preferred option for many diagnostic needs. However, there are some important safety considerations to keep in mind:

Metal Objects and Implants

The powerful magnetic field used in MRI can interact with metal objects, potentially causing harm or affecting image quality. Patients with the following may not be suitable for MRI:

• Pacemakers or other electronic implants
• Certain types of artificial joints
• Metal clips or pins
• Dental implants or braces (in some cases)

It’s essential to inform healthcare providers of any metal implants or objects in your body before undergoing an MRI.

Pregnancy Considerations

While no harmful effects of MRI on fetuses have been documented, it’s generally recommended to avoid MRI scans during pregnancy, especially in the first trimester, unless absolutely necessary. The potential risks are not fully understood, and alternative imaging methods may be preferred when possible.

Claustrophobia and Anxiety

The enclosed space of traditional MRI scanners can trigger claustrophobia or anxiety in some patients. Open MRI machines with larger openings are available at some facilities and may be more comfortable for these individuals. Mild sedation can also be considered in some cases to help manage anxiety during the procedure.

Advantages of MRI Over Other Imaging Techniques

MRI offers several distinct advantages compared to other medical imaging methods:

• No radiation exposure: Unlike X-rays and CT scans, MRI does not use ionizing radiation, making it safer for repeated use and for imaging children and pregnant women (when necessary).
• Superior soft tissue contrast: MRI provides excellent detail of soft tissues, making it particularly useful for examining the brain, spinal cord, and musculoskeletal system.
• Multi-planar imaging: MRI can produce images in any plane without repositioning the patient, offering comprehensive views of anatomical structures.
• Functional imaging capabilities: Techniques like functional MRI (fMRI) can provide insights into brain activity and blood flow.
• No known long-term side effects: Extensive research has not found any significant long-term risks associated with MRI exposure.

Preparing for an MRI Scan: Tips and Guidelines

Proper preparation can help ensure a smooth and successful MRI examination. Here are some key points to consider:

Before the Scan

• Inform your healthcare provider of any medical conditions, allergies, or metal implants.
• Remove all metal objects, including jewelry, watches, and clothing with metal fasteners.
• Avoid wearing makeup, as some cosmetics contain metallic particles.
• Follow any specific instructions provided by your healthcare team, such as fasting requirements for certain types of scans.

During the Scan

• Wear comfortable, loose-fitting clothing without metal components.
• Communicate any concerns or discomfort to the radiographer.
• Stay as still as possible to ensure clear images.
• Use relaxation techniques if you feel anxious in enclosed spaces.

After the Scan

• Resume normal activities unless otherwise instructed by your healthcare provider.
• Drink plenty of water to help flush out any contrast agent if used during the procedure.
• Follow up with your doctor to discuss the results and any next steps in your care plan.

Innovations and Future Developments in MRI Technology

The field of MRI technology continues to evolve, with ongoing research and development aimed at improving image quality, reducing scan times, and expanding clinical applications. Some exciting areas of innovation include:

High-Field MRI Systems

Advanced MRI scanners with higher magnetic field strengths (7 Tesla and above) are being developed to provide even more detailed images and insights into tissue structure and function. These systems offer potential benefits in neuroimaging, musculoskeletal imaging, and cancer detection.

Artificial Intelligence Integration

Machine learning and artificial intelligence algorithms are being incorporated into MRI image reconstruction and analysis processes. These technologies have the potential to improve image quality, reduce scan times, and assist in detecting subtle abnormalities that may be overlooked by human observers.

Portable MRI Systems

Researchers are working on developing smaller, portable MRI machines that could be used in emergency departments, intensive care units, or even in remote locations. These systems could expand access to MRI technology and enable rapid diagnosis in critical situations.

Molecular Imaging

Advances in MRI contrast agents and imaging techniques are enabling visualization of molecular and cellular processes within the body. This emerging field of molecular imaging holds promise for early disease detection, personalized medicine, and monitoring treatment response.

As MRI technology continues to advance, it is likely to play an increasingly important role in medical diagnostics, treatment planning, and research. The ongoing developments in this field hold the potential to further improve patient care and our understanding of human health and disease.

MRI scan – NHS

Magnetic resonance imaging (MRI) is a type of scan that uses strong magnetic fields and radio waves to produce detailed images of the inside of the body.

An MRI scanner is a large tube that contains powerful magnets. You lie inside the tube during the scan.

An MRI scan can be used to examine almost any part of the body, including the:

• brain and spinal cord
• bones and joints
• breasts
• heart and blood vessels
• internal organs, such as the liver, womb or prostate gland 

The results of an MRI scan can be used to help diagnose conditions, plan treatments and assess how effective previous treatment has been.

What happens during an MRI scan?

During an MRI scan, you lie on a flat bed that’s moved into the scanner.

Depending on the part of your body being scanned, you’ll be moved into the scanner either head first or feet first.

Credit:

The MRI scanner is operated by a radiographer, who is trained in carrying out imaging investigations.

They control the scanner using a computer, which is in a different room, to keep it away from the magnetic field generated by the scanner.

You’ll be able to talk to the radiographer through an intercom and they’ll be able to see you on a television monitor throughout the scan.

At certain times during the scan, the scanner will make loud tapping noises. This is the electric current in the scanner coils being turned on and off.

You’ll be given earplugs or headphones to wear.

It’s very important to keep as still as possible during your MRI scan.

The scan lasts 15 to 90 minutes, depending on the size of the area being scanned and how many images are taken.

Read more about how an MRI scan is performed.

How does an MRI scan work?

Most of the human body is made up of water molecules, which consist of hydrogen and oxygen atoms.

At the centre of each hydrogen atom is an even smaller particle called a proton. Protons are like tiny magnets and are very sensitive to magnetic fields.

When you lie under the powerful scanner magnets, the protons in your body line up in the same direction, in the same way that a magnet can pull the needle of a compass.

Short bursts of radio waves are then sent to certain areas of the body, knocking the protons out of alignment.

When the radio waves are turned off, the protons realign. This sends out radio signals, which are picked up by receivers.

These signals provide information about the exact location of the protons in the body.

They also help to distinguish between the various types of tissue in the body, because the protons in different types of tissue realign at different speeds and produce distinct signals.

In the same way that millions of pixels on a computer screen can create complex pictures, the signals from the millions of protons in the body are combined to create a detailed image of the inside of the body.

Safety

An MRI scan is a painless and safe procedure. You may find it uncomfortable if you have claustrophobia, but most people are able to manage it with support from the radiographer.

Going into the scanner feet first may be easier, although this isn’t always possible.

Extensive research has been carried out into whether the magnetic fields and radio waves used during MRI scans could pose a risk to the human body.

No evidence has been found to suggest there’s a risk, which means MRI scans are one of the safest medical procedures available.

But MRI scans may not be recommended in certain situations. For example, if you have a metal implant fitted, such as a pacemaker or artificial joint, you may not be able to have an MRI scan.

They’re also not usually recommended during pregnancy.

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

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

Magnetic Resonance Imaging (MRI): Brain (for Parents)

What It Is

Magnetic resonance imaging (MRI) of the brain is a safe and painless test that uses a magnetic field and radio waves to produce detailed images of the brain and the brain stem. An MRI differs from a CAT scan (also called a CT scan or a computed axial tomography scan) because it does not use radiation.

An MRI scanner consists of a large doughnut-shaped magnet that often has a tunnel in the center. Patients are placed on a table that slides into the tunnel. Some centers have open MRI machines that have larger openings and are helpful for patients with claustrophobia. MRI machines are located in hospitals and radiology centers.

During the exam, radio waves manipulate the magnetic position of the atoms of the body, which are picked up by a powerful antenna and sent to a computer. The computer performs millions of calculations, resulting in clear, cross-sectional black and white images of the body. These images can be converted into three-dimensional (3-D) pictures of the scanned area. This helps pinpoint problems in the brain and the brain stem when the scan focuses on those areas.

Why It’s Done

MRI can detect a variety of conditions of the brain such as cysts, tumors, bleeding, swelling, developmental and structural abnormalities, infections, inflammatory conditions, or problems with the blood vessels. It can determine if a shunt is working and detect damage to the brain caused by an injury or a stroke.

MRI of the brain can be useful in evaluating problems such as persistent headaches, dizziness, weakness, and blurry vision or seizures, and it can help to detect certain chronic diseases of the nervous system, such as multiple sclerosis.

In some cases, MRI can provide clear images of parts of the brain that can’t be seen as well with an X-ray, CAT scan, or ultrasound, making it particularly valuable for diagnosing problems with the pituitary gland and brain stem.

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Preparation

In many cases, a brain MRI requires no special preparation. However, the technician will have your child remove any objects containing metal (such as eyeglasses and jewelry) because they can produce a bright or blank spot on the diagnostic film. You’ll also be asked questions to make sure your child doesn’t have any internal metal clips from previous surgery or anything else that might cause a problem near a strong magnetic field. Electronic devices aren’t permitted in the MRI room.

To get the highest quality MRI results, your child will need to lie still during the scan. For this reason, sedation may be needed, especially for babies and young kids, who often have trouble staying still for the test. Sedation is also helpful for kids who have trouble relaxing in an enclosed space (claustrophobia).

Sedation medicines usually are given through an intravenous (IV) line (small tube in a vein) to help a child stay asleep during the entire test.

If your child will be sedated, food and liquids will be stopped at a certain point before the MRI to allow the stomach to empty. It’s important to notify the MRI technician of any illness, allergy, previous drug reactions, or pregnancy.

You can stay in the MRI room with your child until the test begins, and some centers let parents stay throughout the test. Otherwise, you’ll join the technician in an outer room or be asked to stay in a waiting room.

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Procedure

An MRI of the brain usually takes 30-45 minutes to perform. Your child will lie on the movable scanning table while the technologist places him or her into position. A special plastic device called a coil may be placed around your child’s head. The table will slide into the tunnel and the technician will take images of the head. Each scan takes a few minutes.

To detect specific problems, your child may be given a contrast solution through an IV. The solution is painless as it goes into the vein. The contrast highlights certain areas of the brain, such as blood vessels, so doctors can see more detail in specific areas. The technician will ask if your child is allergic to any medications or food before the contrast solution is given. The contrast solution used in MRI tests is generally safe. However, allergic reactions can occur. Talk to your doctor about the benefits and risks of receiving contrast solution in your child’s case.

As the exam proceeds, your child will hear repetitive sounds from the machine, which are normal. Your child may be given headphones to listen to music or earplugs to block the noise, and will have access to a call button in case he or she becomes uneasy during the test. If sedated, your child will be monitored at all times and will be connected to a machine that checks the heartbeat, breathing, and oxygen level.

Once the exam is over, the technician will help your child off the table; if sedation was used, your child may be moved to a recovery area.

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What to Expect

An MRI exam is painless. Your child may have to lie still on the MRI table for 30-45 minutes during the procedure, but there are brief breaks between each scan. If your child feels cold lying on the MRI table, a blanket can be provided.

Unless sedation was used or you are told otherwise, your child can immediately return to normal routines and diet. Most sedation wears off within 1-2 hours, and any contrast material given should pass through the body in about 24 hours.

Getting the Results

The MRI images will be viewed by a radiologist who’s specially trained in interpreting the scans. The radiologist will send a report to your doctor, who’ll discuss the results with you and explain what they mean. In most cases, results can’t be given directly to the patient or family at the time of the test. If the MRI was done on an emergency basis, the results can be made available quickly.

Risks

MRIs are safe and relatively easy. No health risks are associated with the magnetic field or radio waves, since the low-energy radio waves use no radiation. The procedure can be repeated without side effects.

If your child requires sedation, you may discuss the risks and benefits of sedation with your provider. Also, because contrast solutions can cause allergic reactions in some kids, be sure to check with your doctor before your child receives any solution. There should be medical staff on hand who are prepared to handle an allergic reaction. 

If your child has decreased kidney function, this is an important medical condition to discuss with the radiologist and technician before receiving IV contrast since it may lead to some rare complications.

Helping Your Child

You can help your child prepare for an MRI by explaining the test in simple terms before the examination. Make sure to explain that pictures of the head will be taken and that the equipment will probably make knocking and buzzing noises.

It also may help to remind your child that you’ll be nearby during the entire test.

If an injection of contrast fluid or sedation is needed, you can tell your child that the initial sting of the needle will be brief and that the test itself is painless.

If your child will be awake for the test, be sure to explain the importance of lying still.

If You Have Questions

If you have questions about the MRI procedure, speak with your doctor. You can also talk to the MRI technician before the exam.

Magnetic Resonance Imaging (MRI) – familydoctor.org

Magnetic Resonance Imaging (MRI) is a scan that uses strong magnet and radio waves to see inside your body. It can see your organs, bones and tissue. It creates detailed images of your body. It is a safe and painless way for doctors to get a closer look inside your body. It is used to help diagnose diseases and many other medical conditions.

An MRI is similar to an X-ray (which is used for pictures of your bones). It is similar to a CT scan (also called a CAT scan or computed tomography scan), which is used to create pictures of bones, muscles and organs. It is more like a CT scan than an X-ray. Many people get the two scans confused because the equipment used for each is very similar. Both an MRI and CT scan produce images of your bones, organs, and other internal tissues. Here is how they are different:

• An MRI uses a magnetic field to create an image. This means you aren’t exposed to radiation. No studies have linked MRIs to any harmful health effects. A CT scan uses radiation to create an image. Repeated exposure can be harmful.
• An MRI scan takes longer to perform (30 to 60 minutes, on average). A CT scan is quick (around 5 to 10 minutes).
• An MRI provides a clearer picture of abnormal tissues. It is a better scan for looking at ligaments and tendons, your spinal cord and other soft tissues. A CT scan can give you a higher-quality picture of bones and is better for diagnosing chest and lung problems as well as detecting some cancers.
• An MRI is more expensive than a CT scan. On average, an MRI can cost from $1,200 to $4,000. A CT scan typically costs less than an MRI. The average cost for a CT scan is $1,200 to $3,200.

There are many reasons your doctor may order an MRI. Generally, an MRI can help your doctor identify what is causing your health issue so that he or she can diagnose you accurately and prescribe a treatment plan.

Depending on your symptoms, an MRI will scan a specific portion of your body to diagnose:

• Tumors.
• Heart damage.
• Lung damage.
• Problems with your eyes or ears.
• Sports injuries.
• Problems with your spine, including disc (rubbery cushions between your backbones) problems or spinal tumors.
• Problems with your veins or arteries.
• Brain abnormalities, such as tumors, and dementia.
• Abdominal/digestive tract problems.
• Bone diseases and conditions.
• Pelvic problems (in women) or prostate problems (in men).

Path to improved health

If your primary care doctor thinks you should have an MRI, his or her office staff will call to schedule an appointment for you. Many insurance companies require office staff to call on your behalf to get the scan approved. You will go to a hospital or radiology center for the scan.

Your doctor may ask you not to eat or drink anything a few hours before the MRI, depending on what part of your body you are having scanned. You should mention this when you call to make the appointment.

Your doctor also may request that you have an MRI with contrast. This means that a contrast agent (a dye) will be injected into your body just before the scan. The injection of contrast is most often done through an IV (intravenously, through a vein) that is placed in the back of your hand or the inside of your elbow. The contrast will improve the quality of the images. It may provide more detail in some instances.

You cannot wear jewelry or have metal of any kind on your body (such as on your clothes) during the MRI. In fact, you may be asked to walk through a metal detector before having an MRI. Additionally, if you have metal inside your body, you may not be able to have an MRI. Discuss this with your doctor before scheduling an MRI if you are pregnant or breastfeeding, or if you have:

• Cochlear implants.
• A pacemaker.
• Metal plates, screws, or rods.
• Artificial heart valves.
• An intrauterine device (IUD).
• A drug pump implant.
• Artificial joints.
• Dental fillings, bridges or other metal dental work.
• Worked in the metal working industry (and could have metal dust in your eyes).

MRIs are painless. The only “challenge,” for adults and especially for children, will be lying completely still for the scan. Any movement could result in blurred images, just as they would with a typical camera. The amount of time for the scan will vary, depending on what you are having scanned. Normally, scans last between 15 minutes to an hour.

The MRI machine itself looks like a big donut with a table attached to it. You’ll be asked to lie on the table and a lab assistant or technician will help you into a comfortable position and explain what you can expect during the scan. When you’re ready, the table will slide into the doughnut-shaped opening of the machine. Your whole body does not go in the machine, only the half or part that needs to be scanned.

One thing you’ll need to know is that the machine is noisy. It makes a lot of different noises, and some of them are extremely loud. Some patients say it sounds like a sledgehammer. For this reason, you will be offered headphones. You can listen to music or sometimes even watch a movie. You’ll also be able to hear the radiology technician give you instructions or check on you through the headphones.

If you feel uneasy about the scan, you can request that the technician give you a “panic button” to hold during the process. Pressing the button will signal the technician that you would like to stop the scan and come out of the machine. Some doctors may prescribe a one-time, low-dose anti-anxiety medicine to relax you for the test.

You can also invite a friend or loved one to be with you in the room during the scan, which is very helpful for children’s scans but also makes some adults more comfortable as well. This person also will not be allowed to wear jewelry or metal and will have to go through the same screening process as the person being scanned.

A radiologist (a doctor who specializes in medical imaging) will review the images and send a report to your referring doctor. Your doctor will receive a full report a day or two following the test and can go over the results with you.

Things to consider

Even though having an MRI is safe and painless, it can be a difficult test for persons who are claustrophobic. The MRI machine is never completely closed, but just being even partially in an enclosed area is enough to fill some people with dread. In these cases, it may be possible to use an “open” MRI machine for the scan.

Open MRI machines are, as the name suggests, more open and less confining than the traditional machines. They have larger openings and do not completely surround your body. This makes them a better alternative not only for claustrophobic patients, but also for obese patients or normal-sized males who have larger shoulders.

Small children who are incapable are being still for the duration of the scan may require sedation prior to having an MRI. In this case, an anesthesiologist would provide the sedation and stay (in addition to a nurse) to monitor the patient before, during, and after the scan. Sedation is also sometimes used for patients who are extremely claustrophobic.

If your MRI requires contrast, your radiologist will monitor you for allergies during the procedure. Severe reactions to the contrast agent are rare, but could happen. In those cases, the radiology department is well-trained on how to handle your allergic reaction. 

Questions to ask your doctor

• Why are you ordering an MRI?
• How long will my MRI take?
• Should I fast before my MRI appointment?
• Will the MRI technician need to use contrast material?
• I have metal dental work. Can I have an MRI?
• Can I have an MRI if I am pregnant/breastfeeding?
• When will you have my results?
• Will you notify me of my test results even if they are normal?
• I am claustrophobic. Can I have an open MRI?
• Will my child need to be sedated before having an MRI?
• Does having an MRI increase my chances for getting cancer?

Resources

Food and Drug Administration: MRI (Magnetic Resonance Imaging)

National Institute of Biomedical Imaging and Bioengineering: Magnetic Resonance Imaging (MRI)

National Institutes of Health, MedlinePlus: MRI Scans

Copyright © American Academy of Family Physicians

This information provides a general overview and may not apply to everyone. Talk to your family doctor to find out if this information applies to you and to get more information on this subject.

The world’s strongest MRI machines are pushing human imaging to new limits

On a cold morning in Minneapolis last December, a man walked into a research centre to venture where only pigs had gone before: into the strongest magnetic resonance imaging (MRI) machine built to scan the human body.

First, he changed into a hospital gown, and researchers made sure he had no metal on his body: no piercings, rings, metal implants or pacemakers. Any metal could be ripped out by the immensely powerful, 10.5-tesla magnet — weighing almost 3 times more than a Boeing 737 aeroplane and a full 50% more powerful than the strongest magnets approved for clinical use. Days earlier, he had passed a check-up that included a baseline test of his sense of balance to make sure that any dizziness from exposure to the magnets could be assessed properly. In the MRI room at the University of Minnesota’s Center for Magnetic Resonance Research, he lay down inside a 4-metre-long tube, surrounded by 110 tonnes of magnet and 600 tonnes of iron shielding, for an hour’s worth of imaging of his hips, whose thin cartilage would test the limits of the machine’s resolution.

The centre’s director, Kamil Ugurbil, had been waiting for years for this day. The magnet faced long delays because the liquid helium needed to fill it was in short supply. After the machine was finally delivered, on a below-freezing day in 2013, it took four years of animal testing and ramping up the field strength before Ugurbil and his colleagues were comfortable sending in the first human. Even then, they didn’t quite know what they’d see. But it was worth the wait: when the scan materialized on screen, the fine resolution revealed intricate details of the wafer-thin cartilage that protects the hip socket. “It was extremely exciting and very rewarding,” Ugurbil says.

The US$14-million scanner is one of a handful around the world that are pushing MRI to new limits of magnetic strength. Today, hospitals routinely use machines with field strengths of 1.5 T or 3 T. But ultra-high-field scanners are on the rise. There are already dozens of 7-T machines in research labs around the world, and last year, the first 7-T model was cleared for clinical use in both the United States and Europe. At the extreme end are three scanners designed for humans that reach beyond 10 T. In addition to the University of Minnesota’s machine, researchers are readying two 11.7-T devices for their first tests on people: a gargantuan one for whole-body scanning at the NeuroSpin Centre at CEA Saclay outside Paris, and a smaller one for head scans at the US National Institutes of Health (NIH) in Bethesda, Maryland. Germany, China and South Korea are considering building 14-T human scanners.

The appeal of ultra-high-field scanners is clear. The stronger the magnetic field, the greater the signal-to-noise ratio, which means the body can be imaged either at greater resolution, or at the same resolution, but faster. At 3 T, MRI machines can resolve details of the brain as small as 1 millimetre. That resolution can be as fine as 0.5 millimetres in a 7-T machine — enough to discern the functional units inside the human cortex and perhaps see for the first time how information flows between collections of neurons in a live human brain. Scanners with even higher field strengths are expected to have resolving power that is at least double that of the 7-T devices.

The University of Minnesota’s 10.5-T magnet is delivered and moved into the institution’s Center for Magnetic Resonance Research in this timelapse series.Credit: University of Minnesota

The push to achieve higher field strengths presents a range of challenges. The scanners are bigger, more expensive and more technically demanding. They also require more attention to safety. But work at 7 T has already resulted in gains, researchers say, for both neuroscience and clinical applications: clinicians can guide electrodes for deep-brain-stimulation treatments more accurately, and might also be able to detect osteoarthritis at an earlier stage than was possible before.

The scanners offer detail that was once seen only in thinly sliced postmortem samples imaged by powerful microscopes. “This is a window we’ve just never had in the intact human brain,” says Ravi Menon, a neuroimaging scientist at Robarts Research Institute at Western University in London, Canada.

If you build it

The nuts and bolts of MRI technology have not changed much since the first human scanner was developed in the mid-1970s. The heart of the MRI is still a tube-like superconducting magnet, which generates a static electromagnetic field that realigns a small fraction of the hydrogen protons inside water molecules. Once those protons are lined up, coils in the scanner emit a short burst of radio-frequency waves that cause the protons’ magnetic fields to wobble. When the radio burst ends, the protons release energy, sending out a faint echo of the radio waves that is detected by receiver coils and gives a picture of the anatomy of the brain and other tissue.

The stronger the magnetic field, the greater the fraction of protons that become aligned, and the bigger the energy difference between them and those that remain unaligned. This produces a signal that can be better detected over background noise. But every jump in field strength comes with some uncertainty. “At the beginning of the MRI era, many scientists were thinking that 0.5 T would be the maximum magnet strength for MRI” because they thought the ion conductivity of live tissue would stop radio waves from penetrating far enough inside the body, says Victor Schepkin of the US National High Magnetic Field Laboratory in Tallahassee, Florida. Then, the 1980s saw the emergence of 1.5-T scanners for clinical use. And in 2002, 3-T scanners won approval. Even before then, researchers were pushing for higher field strength; the first 7-T research scanners began to emerge in 1999.

The move from 3T to 7 T presented some challenges. Biological side effects, although temporary, are more pronounced: people can experience dizziness and vertigo when they move in and out of the scanner, researchers say. When people move inside the machine, they can sometimes taste metal, see white flashes or experience involuntary eye movements called nystagmus.

Tissue can also overheat. Because hydrogen nuclei resonate at higher frequencies as the field strength increases, ultra-high-field MRIs must use shorter-wavelength, and thus higher-energy, radio pulses to make the protons wobble. Human tissue absorbs more energy from these waves. So to avoid creating hotspots — and to make usable images — this energy must be smoothed out as much as possible inside the tube. Researchers have devised various ways of accomplishing this. One tactic, says Gregory Chang, a musculoskeletal radiologist at the New York University School of Medicine, is to generate the pulses using a ring of individually tunable transmitters arrayed around the patient.

The fine resolution is also a mixed blessing, because it makes scanners highly sensitive to the slightest motion. Some repetitive movements in the body, caused by breathing or heartbeats, can be modelled and removed. But Menon says that the biggest challenge at 7 T and above — one that is not present in lower-resolution scanners — is involuntary movements of the brain inside the skull. “If I stretch my toes while I’m in the scanner, my brain will move because my toes are connected through the spinal cord to the brain,” Menon says. And thanks to the heartbeats, he adds, the brain pulsates “on the scale of half a millimetre to a millimetre”. Tackling these artefacts is an ongoing area of research, he says.

Even so, scientists say, 7 T has already opened a new window onto the living brain, by revealing structures smaller than 1 millimetre. This regime, dubbed the mesoscopic scale by neuroscientists, is something that previously was accessible only by surgeons, says Klaus Scheffler, head of the magnetic-resonance centre at the Max Planck Institute for Biological Cybernetics in Tübingen, Germany. With 7 T, Scheffler says, “you see all the details without opening the brain”.

Among the structures that have been revealed are the six layers of the cerebral cortex, the 3-millimetre-thick outer region of the brain that is responsible for humans’ high level of cognition. Each layer has a specialization: one handles inputs from other brain areas, some process information and still others convey the outputs of that processing to other parts of the brain. The jump to 7-T machines has enabled researchers to measure the relative activity in different layers, which can reveal how that information is travelling. “That’s the huge advance over imaging at 3 T or 1.5 T,” says Menon. “Normally, we just say A is connected to B, and we can’t tell much about which way the information is flowing.”

The brain of a volunteer is imaged using a 3-T (left) and 9.4-T (right) magnetic resonance imaging machine.Credit: Rolf Pohmann/Max-Planck-Institute for Biological Cybernetics

Some teams have used this capability to measure activity as people undergo verbal and behavioural tests, and the results are illuminating how activity in different layers alters how various areas of the cortex process experiences (S. J. D. Lawrence et al. NeuroImage http://doi.org/cwbr; 2017). “It’s not just that area A is in charge of vision, but that it is modulated by attention, mood, memory,” says Menon. “And those kinds of questions are extremely difficult to answer in animal models. They obviously don’t think or verbalize the way we can.” Now, with 7-T scans of humans, “a picture of human memory is emerging that was really unavailable before”, he says.

Researchers also hope to learn more about the columnar organization of the brain. Cortical columns are thought to carry out computations and respond preferentially to particular stimuli, such as the orientation of objects, although there’s fierce debate over their exact role in this context. Measuring roughly 500-micrometres across, the columns run perpendicular to the cortical layers and communicate with each other through connections in one of the middle layers. If MRI could measure brain activity at a columnar level, scientists might be able to use that to draw conclusions about computations in individual neurons. This would be exciting because one of the limitations of MRI is that it can’t measure neuronal activity directly.

MRI scans at 7 T also provide a better measure of brain connectivity, says Ugurbil, who is involved in the Human Connectome Project. The research effort, which aims to completely map links between neurons in the brain, has performed scans of 184 people at both 3 T and 7 T. At 7 T, they detected many more neural networks and connections between neurons than at 3 T. “In terms of what does that translate into, predicting or studying human diseases, this is still to come,” says Ugurbil.

But Ugurbil says that the machines already show promise for clinical diagnosis and treatment. Deep-brain stimulation, which has been used to treat many people with Parkinson’s disease, is often administered by inserting an electrode into the subthalamic nucleus, part of the basal ganglia deep inside the brain. MRI is used to help surgeons position the electrode, and once it seems to be in place, the electrode is activated to see whether it hit the correct target. But using 1.5- or 3-T machines, “it’s a bit of a fishing expedition”, says Ugurbil. “If you’re not in the right place, you have to pull out your electrode and insert it again slightly differently.” Each time, he says, there is a chance of hitting a blood vessel and causing bleeding. Images taken with 7-T scanners eliminate all this poking around. “You see your target, then you just go: one penetration and you have the result,” he says.

Scans done with 7-T machines have also revealed more about the symptoms and progression of multiple sclerosis. New medications for the disease have helped to slow the advance of motor deficits, and the ensuing gain in patients’ life expectancy and quality of life has meant that cognitive problems have been noticed for the first time. “A lot of these people have what they might describe as [attention deficit hyperactivity disorder]-like symptoms,” says Menon. “We’ve never understood how that could be until now.” Using a 7-T scanner, Menon’s group has been able to spot lesions in areas where they previously had not been observed, including the dorsolateral prefrontal cortex, an area responsible for executive function and attention. “Historically, those were quite hard to see,” he says. These lesions might explain why the patients develop cognitive symptoms. Menon is involved in a major project “looking at the relationship between cognitive function and the location of lesions”, he says.

If greater resolution is not needed, clinicians can also use the higher signal-to-noise ratio in an ultra-high-field MRI to simply scan more quickly, creating images in seconds that would otherwise take minutes, and images in minutes that would otherwise take hours. For patients, this can make a big difference in comfort.

Researchers can also look beyond water. At field strengths of 7 T and higher, MRI can detect not only hydrogen nuclei, but also the nuclei of heavier elements, such as sodium, potassium, phosphorus and fluorine, which have a much lower intrinsic sensitivity to magnetic resonance than hydrogen nuclei do.

Chang has used New York University’s 7-T scanner to look at sodium for biochemical changes that might presage osteoarthritis. The evidence suggests that in people with early stages of the disease, he says, “the sodium concentration in their cartilage goes down without any change in the structure of the cartilage”. Several other groups have replicated the results in small studies. Chang hopes that if they hold up, the approach could be used to detect osteoarthritis early enough to prevent further damage by making lifestyle modifications and to allow researchers to perform clinical trials more quickly, because they get an early indicator of the disease.

Beyond 7

The world’s most powerful MRI scanner sits in the US National High Magnetic Field Laboratory. With an interior space just 10.5 centimetres in diameter, the 21.1-T machine is too small to be used on people. Schepkin and his colleagues there scan small animals instead. They have used the scanner to study, for instance, the sodium concentration in rat brain tumours, and their results suggest that the amount of sodium present in a tumour can indicate how resistant it would be to chemotherapy (V. D. Schepkin et al. Magn. Reson. Med. 67, 1159–1166; 2012).

At first, Schepkin says, there was some hesitation around using the imager. “We had a rule that nobody can work near the magnet alone,” he explains. That rule is no longer in place, but the group does still observe a strict ‘no metal’ policy.

It took years to prepare the scanner, which was not a fully commercial machine, for animal testing. The process has been similarly slow for many of the new human-research scanners beyond 10 T. The NIH, for example, is currently awaiting the return of its 11.7-T magnet. After it was delivered in 2011, the team turned some of the scanner components on and off too quickly, causing the magnet to overheat and damage some wiring, an imaging researcher at the agency says. The magnet needed a factory rebuild; it is expected back in 2019. The 5-metre-diameter magnet for the 11.7-T MRI at the NeuroSpin Centre in France was delivered last May. The scanner is slated to produce its first scans of live human brains in 2022.

Ugurbil received US Food and Drug Administration clearance in August 2017 to scan 20 people with his 10.5-T MRI (the man in December was the first). He expects to scan the first human brain in a few months. Scans at this field strength are at the point where researchers are not looking to answer any biomedical questions, but simply testing whether the process has any side effects. Still, he says, “even the starting images look pretty spectacular”. He is part of a group discussing efforts to reach 20 T in humans.

The amount of heating generated by such machines could be even more problematic. Some researchers have speculated that scanners operating above 14 T could also cause nerve conductance to slow down, stimulate peripheral nerves or damage DNA, although Schepkin says he has seen none of these effects so far in animals, even at 21.1 T. Still, Scheffler thinks that at some point there will be a limit to field strength beyond which we can’t go without damaging the body: “I don’t think we can go higher and higher forever.”

MRI scan | Tests and scans

• MRI (magnetic resonance imaging) is a type of scan that uses magnetism and radio waves to take pictures of inside the body.
• The scan takes between 15 and 90 minutes.
• You might have one to find out whether you have cancer and if you do to measure how big it is and whether it has spread. You might also have one to see how well treatment is working.
• It is a safe test. If you have an injection of contrast dye it can cause a headache, dizziness or a warm flushed feeling

An MRI is a type of scan that creates pictures using magnetism and radio waves. MRI scans produce pictures from angles all around the body and shows up soft tissues very clearly. 

MRI stands for magnetic resonance imaging.

They take between 15 and 90 minutes. 

Why you might have it

MRI can be used to look at most areas of the body. For some parts of the body and for some types of tissues, it can produce clearer results than a CT scan.

An MRI can be used to:

• find a tumour
• find out how big it is and whether it has spread (stage a cancer)
• measure blood flow
• to check how well treatment is working

You might have an injection of a special dye (contrast medium) before the scan to help make the pictures clearer.

MRI is particularly good for :

• brain tumours
• primary bone tumours
• soft tissue sarcomas
• tumours affecting the spinal cord
• tumours in the pelvic organs (prostate, bladder, uterus and ovaries)

MRI instead of CT scans

In some situations, your doctor may suggest MRI if a CT scan hasn’t been able to give all the information they need.

In some cancers, such as cervix or bladder cancer, MRI is better than CT at showing how deeply the tumour has grown into body tissues. It can be particularly useful for showing whether the tissue left behind after treatment is cancer or not.

Preparing for your MRI scan

Before you go to your appointment, or when you arrive, you fill in a safety checklist. This asks about:

• any operations you’ve had
• whether you have any metal implants or other metals in your body

An MRI scan uses strong magnetism which could affect any metal in your body. This includes:

• pacemakers or an implantable defibrillator (to treat abnormal heart rhythms)
• surgical clips, pins or plates
• cochlear implants (for deafness)
• metal fragments anywhere in your body – for example from an injury, dental fillings and bridges 

You can still have an MRI scan if you have some metals in your body, but your doctor and radiographer decide if it’s safe for you. Tell the scanner staff about any metals in your body.

Some people feel claustrophobic or closed in when they’re having an MRI scan. Contact the department before your test if you’re likely to feel like this. The hospital staff can take extra care to make sure you’re comfortable and that you understand what’s going on. Your doctor can give you medicine to help you relax if you need to.

An MRI is generally safe during pregnancy. But as a precaution, you usually won’t have one during the first 3 months of your pregnancy.

Tell the department staff beforehand if you think you’re pregnant. 

What to expect

When you arrive at the scanning department, the radiographer might ask you to change into a hospital gown. You might not have to undress if your clothing doesn’t have any metal, such as zips or clips. 

You have to:

• remove any jewellery, including body piercings and your watch
• remove your hair clips
• empty your pockets of coins and keys

It’s safe to take a relative or friend into the scanning room with you. But check with the department staff first. Your friend or relative will also need to remove any metal they have on them.

In the scanning room

Your radiographer takes you into the scanning room. The MRI machine is large and shaped like a doughnut.

You lie on your back on a couch that can slide into the MRI machine. 

You might have an injection of a dye (contrast medium) through a small plastic tube (cannula) into a vein in your arm. This helps to show up your body’s organs more clearly. Some people are allergic to the dye, so your radiographer will check first about any medical conditions or allergies you have.

After the dye injection you may:

• feel sick
• have a headache
• feel warm or flushed
• have a metallic taste in your mouth
• feel a little dizzy

These effects are usually mild and last for a short time. Tell your radiographer if you feel unwell at any point during or after your scan.

Having the MRI scan

You need to lie as still as possible. The scan is painless but it can be uncomfortable to stay still. Tell them if you’re getting stiff and need to move. 

Once you’re in the right position on the couch, your radiographer leaves the room. They can see you on a TV screen or through a window at all times from the control room. You can talk to each other through an intercom.

The couch moves through the MRI scanner. It takes pictures as you move through it. Your radiographer might ask you to hold your breath at times. 

The scanner makes a very loud clanging sound throughout the scan. You wear headphones to protect your hearing. You can also listen to music. Keeping your eyes closed can help.

This 1 minute video shows you what happens when you have an MRI scan.

Voiceover: This is an MRI scanner.

This type of scan uses magnetism to build up a picture of the inside of your body to help your doctor either make a diagnosis and decide what treatment you need or to find out if your treatment is working.

The radiographer makes sure you are lying in the correct position on the couch and explains what will happen.

You need to lie as still as possible.

MRI scans are very noisy so you wear ear plugs or headphones. During the scan you won’t feel anything.

The space you lie in can feel small, if you think you will find it difficult being in a small space, contact the scanning department before your appointment.

The radiographer controls the scan from a separate room but they will be able see and hear you throughout.

Here you can see an example of an MRI scan.

Once the scan is finished you can go home.

After your scan

When the scan is over, your radiographer comes back into the room and lowers the couch so that you can get up.

You usually stay in the department for about 15 minutes after your scan if you’ve had the dye. This is in case it makes you feel unwell.  

Your radiographer removes the cannula from the vein in your arm before you leave.

You should then be able to go home or back to work, and also eat and drink normally.

Possible risks

An MRI is very safe and doesn’t use radiation. Some people can’t have an MRI but the checklist picks this up beforehand. Your doctor and radiographer make sure the benefits of having the test outweigh any possible risks. The risks include: 

Bruising and swelling

You might get a small bruise around the area where they put the needle in for the cannula. 

There’s a risk that the contrast medium will leak outside the vein. This can cause swelling and pain in your arm but it’s rare. Tell your radiographer if you have any swelling or pain. Let your GP know if it doesn’t get better or starts to get worse when you’re at home.

Allergic reaction 

An allergic reaction to the contrast medium injection is rare. This most often starts with feeling weak, sweating and difficulty breathing. Tell your radiographer straight away if you feel unwell so they can give you medicine to control the reaction.

Getting your results

You should get your results within 1 or 2 weeks. 

Waiting for results can make you anxious. Ask your doctor or nurse how long it will take to get them. Contact the doctor who arranged the test if you haven’t heard anything after a couple of weeks.

You might have contact details for a specialist nurse who you can contact for information if you need to. It may help to talk to a close friend or relative about how you feel.

For information and support, you can call the Cancer Research UK nurses on freephone 0808 800 4040. The lines are open from 9am to 5pm, Monday to Friday.

More information

We have more information on tests, treatment and support if you have been diagnosed with cancer.

Orthopaedic Magnetic Resonance Imaging | Cedars-Sinai

Magnetic resonance imaging can be used to:

• Diagnose disorders of the central nervous system, such as multiple sclerosis
• Identify brain or spinal tumors or other chronic disorders of the nervous system
• Diagnose pituitary gland diseases
• Find eye or inner ear tissue abnormalities
• Identify bone and joint damage from injuries, degenerative disorders and tumors
• Identify infections of the bones and joints

Before an MRI, remove any clothing, wigs, and appliances such as hearing aids, dentures and jewelry that may contain metal or electronics. If you have metal or electronic devices in your body such as artificial joints or heart valves, a pacemaker or rods, plates or screws holding bones in place, be sure to tell the technician. Metal may interfere with the magnetic field used to create an MRI image and can cause a safety hazard. The magnetic field may damage electronic items.

Do not have an MRI scan if you have an implantable cardioverter defibrillator or pacemaker. The strong magnetic field created by the MRI unit may interfere with how these devices work.

If you are pregnant or think you may be, be sure to tell the technician before having an MRI. The effects of magnetic fields on fetuses aren’t well understood. It may be necessary to use a different type of test or postpone an MRI if you are pregnant.

Most MRI machines are large, cylindrical magnets. The strong magnetic field is produced by sending an electric current through wire loops or coils inside the unit. Other coils in the unit send and receive radio waves.

While you are inside the machine, radio waves are sent to your body, which responds by sending faint signals back. The MRI machine senses the signals and sends them to a computer, which then generates an image.

The image is a composite, three-dimensional picture of your body. A cross-sectional slice through your body at any point can be electronically generated from the picture. This image can then be seen on a video monitor. The images can also be put on photographic film.

When you are having an MRI, you lie on a table that slides into the opening of the magnet. A technician monitors you from another room and can talk to you through a microphone or intercom. You won’t feel anything as the MRI generates a strong magnetic field around you and directs radio waves at your body. Nothing moves around you. You may hear tapping, thumping or other sounds from inside the machine. You may be given earplugs or music to listen in order to block the noise.

It typically takes 30 to 90 minutes to do an MRI. It is important to lie still and breathe quietly as movement can blur the images. If being in an enclosed space makes you anxious, talk to your doctor before the MRI.

Sometimes a dye or contrast agent is injected into your veins to enhance how certain tissues or blood vessels look in the images. The dye or contrast agent used in an MRI is different than those used in computerized tomography scanning. They don’t contain iodine and aren’t as likely to cause an allergic reaction.

As with X-rays or CT scans, a radiologist who is trained to read the images will review the results of your MRI and make a report to your doctor or surgeon.

While MRIs are relatively new technology, advances are continuing to be made. These advances include:

• Functional MRIs, which make it possible to measure split-second nerve cell activity in parts of the brain
• Spectroscopic MRIs, which measure certain metabolites in the body, helping doctors to diagnose and treat conditions such as cancer or infections
• Diffusion MRIs, which create an image based on the microscopic movement of water in the spaces outside the cells
• Stronger magnets that allow for more detail and faster imaging than conventional MRI machines

More information on preparing for your MRI.

Magnetic Resonance Imaging (MRI)

This article tells you about a magnetic resonance imaging (MRI) scan, including MRI + angiography, MRI + venography and MRI +
angiogram. It includes the benefits and the risks, what happens before, during and after having a MRI scan or procedure.

What is a MRI scan?

Some of the things MRI scans are used to look at are:

MRI

• The brain and spinal cord
• Bones and joints
• The back
• Liver and bile ducts

MRI + angiography

MR Angiography uses MRI to look at blood vessels in your brain, neck, heart, lungs, kidneys and legs.

MRI + venography

MR Venography uses MRI to show your veins.

MRI + arthrogram

An MR Arthrogram uses MRI to look at your joints after a special liquid is injected into a joint.

Benefits associated with a MRI Scan

• Very detailed diagnostic pictures of inside your head, body, legs, arms and joints
• Generally painless
• Does not use radiation
• MR angiography and venography can show problems, including clots in your arteries and veins without using surgery

Risks associated with a MRI Scan

Your doctor knows the risks of having a MRI scan. Your doctor will consider the risks before recommending you to have a MRI
scan.

Possible risks are:

• Often not recommended in early pregnancy
• 
  You must tell staff if you have
• A pacemaker
• A cochlear implant
• A spinal stimulator
• Metal implants, including aneurism clips, other surgical clips or staples, metal rods or pins in your bones, or false
  teeth
• Any pieces of metal in your eyes
• 
  The presence of these objects may add to the risk of having an MRI scan and may cause it to be cancelled

If you are having ‘dye’, there is a very small risk of:

• An allergic reaction (usually mild and easily controlled by medication)
• Infection at the site of an injection

If you are at all concerned regarding the risks, talk to your doctor before the examination.

Preparation for a MRI Scan

• Bring your referral letter or request form and all x-rays taken in the last 2 years with you
• Leave the x-rays with the radiology staff as the doctor may need to look at them. The MRI staff will tell you when these are
  ready to be picked up
• Wear comfortable, loose clothing
• Leave all jewellery and valuables at home (metal objects, such as watches, keys, coins and jewellery cannot be taken into the
  MRI room. Cards with magnetic strips such as bank cards will be erased by most MRI scanners)

If you are having ‘dye’:

• You may be asked not to eat or drink for a few hours before the MRI Scan

Important to tell your doctor before the scan

• If you are or may be pregnant
• If you don’t like closed in spaces (claustrophobic). Your doctor may then discuss the possibility of you being given
  something to relax you just before the scan (sedative). If the doctor has decided you need a sedative and written it on the request
  form, you will need to let the staff know when you book your scan
• If you are having ‘dye’ tell the staff about any medical conditions you have, including kidney disease, allergies and
  asthma (some conditions such as kidney disease may mean you cannot have an MRI with dye)

Just before the MRI scan

• You may be given a gown to wear during the procedure
• You will be asked to remove any metal objects
• You may be given a sedative if you don’t like closed in spaces. (claustrophobic). The sedative will relax you and may make
  you feel sleepy

Consent

You have the right to refuse an examination and may do so if you wish. You may be asked to complete a consent form.

What happens during a MRI scan

The staff will ask you to lie on the bed, and will place a receiver around the part of your body being scanned. Straps or
pillows may be used to help you keep still during the scan, however you will be able to remain comfortable.

If you are having dye or sedative injected, MRI staff will put a needle into a vein in your hand or arm.

Possible side effects of ‘dye’:

• You may feel a slight coolness and a flushing for a few seconds
• Part of your body may feel warm – if this bothers you, tell the staff

The MRI machine makes a lot of noise during the scan, which may sound like thumping or humming. You will be given earplugs or
headphones to block out the noise or listen to music. (In most MRI centres you can bring your own CD to listen to).

The staff will leave the room where they can control the movement of the bed from behind a screen. They can see, hear and speak
to you at all times. You will be able to speak to them at all times. They will tell you what is happening, when to hold still and
if you need to take a deep breath and hold it. If you get stiff, need to move or are feeling closed in (claustrophobic), tell the
staff.

The MRI staff will use a remote control to slowly move you into the tunnel of the MRI scanner.

When the scanning is finished you will be asked to wait while the staff check the pictures.

The scan, including getting you ready, takes between 30 minutes to one hour.

When will I get the results?

The amount of time it takes for you to get your results will differ depending on where you get your scans done. The radiology
doctor will look at the pictures and write a report. The pictures may be on films or on a CD.

Ask whether you should wait to take the pictures and report with you, or whether they will be sent to your doctor.

Your doctor will need to discuss the report with you. You will need to make an appointment to do this.

After the MRI scan

You will be able to go soon after the MRI is finished and can continue with normal activities.

If you had ‘dye’:

• Staff will need to take out the needle if it is still in your arm Staff will give you any special instructions
• The dye will pass out of your body in your urine. You will not notice it as it is colourless
• Drink plenty of fluid to help get rid of the dye

If you had a sedative

• Staff will need to take out the needle if it is still in your arm
• 
  You must not drive a car or take public transport and must have someone with you for 24 hours afterwards
• 
  You must not operate machinery on the day of the scan

Costs

For an Australian patient in a Public Hospital in Western Australia

• Public patient – no cost to you unless advised otherwise
• Private patient – costs can be claimed through Medicare and your health insurance provider

For a patient in a Private Hospital or Private Imaging Site in Western Australia or a patient outside Western Australia

• Ask your doctor or the staff where you are having your test done what the cost will be

Further information

For more detailed information please access MRI from InsideRadiology at:
www.insideradiology.com.au

This is a resource produced especially for consumers by the Royal Australian and New Zealand College of Radiologists:
www.ranzcr.edu.au

A guide to gathering information that you may need for making informed decisions is
published by the Consumers’ Health Council of Australia at:
https://chf.org.au

Or for other relevant information access the Diagnostic Imaging Pathways website at:
www.imagingpathways.health.wa.gov.au/index.php/consumer-info

Or if you have questions or require any further information please contact your doctor or speak to the staff where you are going
to have your procedure.

Consumer participation

This information has been reviewed by representatives from the following groups:

• Aboriginal people
• People with disabilities
• Seniors
• CALD (Culturally and Linguistically Diverse)
• The Health Consumers’ Council

Feedback

All feedback, comments and suggestions regarding consumer information at Diagnostic Imaging Pathways are welcome. Please direct
them to the following email address:
This email address is being protected from spambots. You need JavaScript enabled to view it.

Disclaimer

This article is intended as general information only. The Department of Health cannot accept any legal liability arising from
its use. The information is kept as up-to-date and accurate as possible, but please be warned that it is always subject to
change

Copyright

© Copyright 2017, Department of Health Western Australia. All Rights Reserved.
This article and its content has been prepared by The Department of Health, Western Australia and is protected by copyright.

Date reviewed: July 2017

Date of next review: July 2019

1_MR layout_Basics of safety for magnetic resonance imaging

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What You Should Know About MRI Scanning – MRI Magnetics Center in Yekaterinburg

MRI uses strong magnetic fields and radio waves to create detailed images of organs and tissues in the body.

The development of MRI has revolutionized the world of medicine https://www.eurekalert.org/pub_releases/2008-02/aiop-ttf022808.php. Since its discovery, doctors and researchers have developed methods to use MRI scans to aid in medical procedures and research.

MRI Scan Facts:

Here are some key points about MRI scanners.

The MRI scan is a non-invasive and painless procedure

Raymond Damadian created the first full-body MRI scanner, which he called “Indomitable”.

The cost of an MRI scanner starts at $ 150,000.

What is an MRI scan?

The

MRI scan uses a large magnet, radio waves and a computer to create a detailed image of a patient’s internal organs and tissues.

The scanner itself usually resembles a large tube with a table inside, allowing the patient to slide into a tunnel on the table.

MRI scans are different from CT scans and X-rays because they are not based on ionizing radiation, which can be potentially harmful to the patient.

Benefits

The development of the MRI scan represents a huge milestone in the medical world as doctors, scientists and researchers can now accurately examine the interior of the human body with a non-invasive instrument.

The following are just a few examples where an MRI scanner is used:

Anomalies of the brain and spinal cord

Tumors, cysts and other abnormalities in various parts of the body

Joint injury or malformation

Certain types of heart problems

Diseases of the liver and other abdominal organs

Diagnosis of pelvic pain in women (for example, fibromas, endometriosis).

Congenital malformations of the uterus in women undergoing examination for infertility

Preparation:

MRI scans require little or no preparation.Upon arrival at the department, doctors may ask the patient to change into specialized clothing or take off existing ones. It is important that the patient does not bring metal objects into the scanner, so the patient will be asked to remove any metal jewelry or accessories that might interfere with the operation of the machine.

Sometimes patients are given intravenous contrast fluid to improve the appearance of certain body tissue.

The radiologist will then talk about the MRI scan process and, if necessary, can answer any questions you may have about the scan.

As soon as the patient enters the scanning room, he will need to lie down on a dedicated table. Staff will provide a comfortable desk seating by providing blankets or pillows.

Headphones or acoustic earplugs will be provided to block out loud scanner noises. Headphones are very popular with children as they can listen to music without worry.

During MRI scan

During the examination, the MRI specialist can speak to the patient through the speakerphone.It will not start scanning if the patient is not ready.

Stay stationary during scanning. Any movement will disrupt the created images, much like a camera trying to take a picture of a moving subject. Loud sounds will come from the scanner, which is completely normal. If the patient feels uncomfortable during the procedure, he can talk to the MRI specialist through the speakerphone and ask him to stop scanning, or press the signal bulb in his hand.

After MRI scan

After the scan, the radiologist will examine the images to check if any additional images are needed. If the radiologist is satisfied with the programs, the patient can be released.

MRI scanner contains two powerful magnets; these are the most important pieces of equipment.

The human body is mainly composed of water molecules, which are composed of hydrogen and oxygen atoms. At the center of each atom is an even smaller particle called a proton, which is sensitive to any magnetic field.

Normally, the water molecules in our bodies are randomly arranged, but upon entering the MRI scanner, the first magnet forces the body’s water molecules to align in one direction.

The second magnetic field is then turned on and off in a series of rapid pulses, causing each hydrogen atom to change its alignment, and then, when turned off, quickly returns to its original relaxed state. A magnetic field is created by passing electricity through the gradient coils, which also vibrates the coils, resulting in a pounding sound inside the scanner.

Although the patient cannot feel these changes, the scanner can detect them and, when combined with the computer, can create a detailed cross-sectional image for interpretation by the radiologist.

Functional magnetic resonance imaging

Functional magnetic resonance imaging or functional MRI uses MRI technology to measure brain activity by monitoring blood flow in the brain. This provides insight into the activity of neurons in the brain as blood flow increases in areas where neurons are active.

This method revolutionized brain mapping, allowing researchers to assess the brain and spinal cord without the need for invasive procedures or drug injections.

fMRI helps researchers learn about the function of a normal, diseased, or damaged brain.

Functional MRI is also used in clinical practice because, unlike standard MRI scans, which are useful for detecting structural abnormalities in tissues, functional MRI scans can help detect abnormal activity in these tissues.Thus, it is used to assess the risks associated with brain surgery by helping the surgeon identify areas of the brain involved in critical functions such as speech, movement, perception, or planning.

Functional MRI can also be used to determine the effects of tumors, stroke, head and brain injury, or neurodegenerative diseases such as Alzheimer’s disease.

How long will it take to complete an MRI scan?

MRI scans vary from 20-60 minutes depending on which part of the body is being analyzed and how many images are required.

If the images are not clear enough to the radiologist after the first MRI scan, the patient may be asked to have a second scan.

I have braces, do I have to get tested?

Although staples and fillings are not susceptible to scanning, they can distort the image. The treating doctor and radiologist can discuss this beforehand. The MRI scan may take longer if additional images are required.

90,000 Side effects after MRI with contrast

Magnetic resonance imaging is safe and painless for the patient.The method does not require invasive manipulations, the exception is intravenous injection of the solution during the contrast procedure. The essence of MRI is in using the phenomenon of magnetic resonance: water molecules in cells change position and line up in a special way under the action of a directed induction field.

The severity of tissue response depends on the saturation of the latter with moisture, loose structures provide an intense response, bones and cartilage give a weak signal. The information is read by detectors installed in the tomograph.

A sophisticated computer program converts the data into layer-by-layer images of the study area. Scanning is done in axial, sagittal and coronary projections; if necessary, the doctor reconstructs a 3D model of the examined area.

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To increase the information content of an MRI, contrast enhancement is used. The patient is injected intravenously with a solution of gadolinium.Filling the vascular bed and intercellular space, the drug visualizes the nature of the blood supply to the area in question, shows the slightest changes in the structure of the anatomical formation. Side effects after MRI with contrast are rare and are associated with the characteristics of the patient’s health.

Benefits of having an MRI

The main advantage of magnetic resonance imaging is its high information content in assessing the state of internal organs and structures. The images obtained reflect changes in the shape, size, structure of anatomical formations.The method is used in diagnostics:

• inflammatory processes;
• degenerative-dystrophic changes;
• benign formations;
• ischemic events;
• primary malignant neoplasms and metastases;
• traumatic injuries of soft tissues, blood vessels, nerves;
• demyelinating diseases;
• anomalies in the structure of internal organs;
• vascular pathologies, etc.

Magnetic resonance imaging is used with insufficient information content of other types of instrumental examination.

Contrast MRI allows you to see neoplasms with a diameter of 3 mm, diagnosing neoplastic processes in the early stages. If there is a suspicion of pathological conditions of the vascular system, scanning makes it possible to determine the focus of damage, to suggest the causes of the disease, to clarify the nature of the process and the consequences of impaired blood supply.

Magnetic resonance imaging is effective in examining the brain and spinal cord. Tomograms show the slightest changes in neural structures, allowing you to timely determine the nature of pathological changes and choose the optimal method of treatment.

Contrast MRI of the brain

Popular “tales” about the dangers of MRI

An abundance of conflicting information about the procedure for magnetic resonance imaging is the reason for the increased nervousness of patients before the examination. Often there are negative reviews, which are based on a lack of understanding of the features of the method.

Some patients believe that the phenomenon of nuclear magnetic resonance has a negative effect on human health: it inhibits the functioning of the central nervous system, impairs the quality of blood, and causes changes in joints and muscles.This opinion is erroneous. As a result of the research, the influence of the induction field on the state of internal organs and structures was not revealed. The resonance of hydrogen nuclei in water molecules does not affect the work of cells and passes without a trace after the end of the generator of the electromagnetic pulse.

Another myth about the dangers of scanning is the appearance of pain after MRI with contrast. A solution of gadolinium chelates is excreted from the body with feces and urine, this process takes no more than a day. The drug spreads along the vascular bed and penetrates into the interstitial space without affecting the functioning of cells.In a healthy person, the use of contrast enhancement during scanning does not cause pain. Deterioration in well-being can be triggered by existing pathologies.

MRI series of the spine (sagittal and axial projections)

Popular misconception: doctors and X-ray technicians are behind a partition due to the negative effects of MRI. Complex equipment during operation is sensitive to third-party electromagnetic impulses. A computer, mobile phone, metal objects located near the device can distort the image and cause damage to the tomograph.Medical personnel are located in the adjacent room to exclude any extraneous impact on the operation of the device.

It is believed that the induction field used for scanning stimulates the growth of malignant tumors. There is no connection between the effect of a magnet and the processes of malignancy. As a result of MRI, formations that were previously unnoticed due to their small size can be detected. The method allows you to see the already existing tumors, if necessary, the doctor recommends a biopsy, on the basis of which the final diagnosis is made.

Harmful radiation exposure is another MRI myth. Magnetic resonance scanning is carried out without the use of ionizing streams. The study does not give a dangerous radiation exposure and can be used in patients with contraindications to radiography.

Parents are unnecessarily afraid to conduct an MRI scan at an early age. The study does not affect the growth and development of the body; restrictions on the contrast procedure are associated with the peculiarities of intravenous injections for children.

MRI photo of Ewing’s sarcoma

Magnetic resonance imaging is one of the most harmless types of hardware diagnostics. It is possible to prevent the development of undesirable consequences by observing safety rules during the procedure.

Side effects after MRI with contrast

Discomfort can be triggered by violation of individual restrictions. Contraindications to the appointment of MRI are:

• fixed metal prostheses, pins, implants, vascular clips, etc.;
• implanted electromagnetic devices;
• first trimester of pregnancy;
• tattoos made with ferromagnetic inks.

In the terminal stages of kidney and liver diseases, contrast enhancement is not used.

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Among the relative restrictions:

• claustrophobic;
• tendency to allergic reactions;
• overweight patient (over 120 kg with abdominal girth over 150 cm).

Side effects occurring with MRI with contrast are of different nature. Interaction of the patient’s existing metal-containing prostheses, tattoos, etc. with a magnetic field can be accompanied by unpleasant sensations: burning, itching, pain. Electronic devices fail when in contact with the tomograph.

Removing the “staining” solution from the body increases the burden on the liver and kidneys. In case of serious pathologies of the filtration organs, contrast MRI leads to the decompensation of these diseases.Systemic nephrogenic fibrosis and retention of gadolinium chelates in the body are extremely rare. Acute kidney damage is characterized by a sharp deterioration in the patient’s well-being.

The drug used for contrast enhancement is hypoallergenic, but with individual intolerance to the components of the solution, local reactions are possible: reddening of the skin, itching at the injection site, tissue edema, rash.

Postoperative MRI of the head with contrast (in three projections)

Patients with claustrophobia are prone to panic attacks.There is a high probability of an attack occurring when you are in the confined space of the apparatus tunnel. Fear can provoke:

• tachycardia;
• dizziness;
• pain in the abdomen;
• nausea;
• feeling of lack of air.

Similar side effects appear in patients with increased anxiety, unstable psycho-emotional background.

Headache (cephalalgia), nausea, weakness, heart palpitations, sweating during the procedure may indicate the presence of vegetative-vascular disorders.

Discomfort after magnetic resonance imaging is experienced by persons suffering from cervical osteochondrosis. Scanning with contrast takes about 30 minutes. During this time, the patient must remain motionless, which is accompanied by impaired blood flow in the great vessels. An increasing headache, tinnitus, weakness may appear.

People with cardiovascular diseases report negative consequences after MRI with contrast. Weakness, nausea, and an increase or decrease in blood pressure are possible.Side effects are associated with pathological changes in tone, vascular patency, increased permeability of the walls of veins and arteries.

Dyspeptic symptoms may occur with overeating before the procedure. Contrast MRI is recommended after a light snack. Examination of the abdominal and pelvic organs is done on an empty stomach, the main meal is allowed 4 hours before the scan. But immediately before the procedure, it is advised to eat something light.

Tomogram of the pelvic organs in a woman (frontal projection)

How long do the side effects last?

Discomfort occurs during the procedure or within 1-1.5 hours after the administration of a contrast agent.The duration of the side effects depends on the cause.

Ailments caused by overeating or fasting before the procedure disappear within a few hours. Pain due to cervical osteochondrosis subside after the restoration of the patency of the great vessels. If untreated, cephalalgia returns and becomes regular.

If the deterioration in well-being is caused by cardiovascular pathologies, autonomic disorders, individual intolerance to a solution of gadolinium salts, the patient will feel an improvement as the contrast is removed from the body.The cleansing process takes 1-2 days, depending on the age and general health of the subject.

Elderly people, persons with metabolic disorders note the disappearance of side effects after 48-72 hours. Young, active patients fully recover within a day after the procedure.

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How to remove contrast from the body after an MRI?

Compliance with the drinking regime helps to speed up the process of cleansing the body.Nutritionists recommend drinking clean, non-carbonated water.

Withdrawal of contrast occurs naturally, with the participation of the kidneys and liver. There is no need to stimulate the filtration organs. Avoiding confectionery, fatty, fried, spicy, salty foods helps to reduce the load and speed up the cleansing.

During the first day after the examination, doctors recommend avoiding overeating, stress, excessive exertion, it is advisable to limit smoking.

Is alcohol allowed after MRI with contrast?

Ethyl alcohol has a toxic effect, destroys liver cells, affects the functioning of blood vessels, irritates the mucous membrane of the gastrointestinal tract.Slight sedation resolves quickly. Patients who want to relieve excessive nervousness with alcohol run the risk of increasing the intensity of side effects (headache, nausea, dyspepsia).

Drinking alcohol slows down metabolic processes, increases the load on the filtration organs and slows down the elimination of the “staining” solution. Doctors recommend not drinking alcohol after MRI with contrast. The limitation period depends on the patient’s condition (from 1 to 3 days).

What should I do if I feel unwell after MRI with contrast?

Pre-preparation helps prevent potential negative effects of Magnified Resonance Imaging (MRI) scans. With claustrophobia, increased nervousness, severe pain syndrome, the patient, on the recommendation of a doctor, takes sedatives and painkillers.

If a person feels unwell during the scan, you can use the panic button. When pressed in a room occupied by medical personnel, a signal sounds, the procedure is stopped.

In the event that a patient becomes ill after an MRI with contrast, it is necessary to check the compliance with safety measures. The appearance of a metallic taste in the mouth, severe headache, nausea, weakness are the reasons for seeking medical attention. If necessary, the specialist will prescribe symptomatic treatment (analgesics, sedatives).

The underlying pathological process can become the cause of the malaise. In this case, the doctor may recommend an additional examination to diagnose the disease.

Malignant brain tumor on MRI scan

Clinic “Academy of MRI” offers an additional discount to patients who have applied again. There are special prices for examination at night and in the direction of the attending physician. You can sign up for an MRI on the clinic’s website and by calling the contact number 8 (812) 648-23-49.

The medical center provides free consultations by phone, the patient is told about the features of magnetic resonance imaging.A conversation with a radiologist allows you to properly prepare for the procedure, which reduces the risk of negative consequences.

The speed and quality of MRI scans were improved thanks to metamaterials

An international team of scientists, which included employees of the international laboratory “Applied Radiophysics” of ITMO University, found a way to increase the resolution of the MRI scanner, while making the procedure itself faster and safer for the patient.This was achieved by placing a special substrate of ultrathin metal resonators inside the MRI scanner, which are capable of amplifying and redistributing the electromagnetic field in space. The technology is at the patenting stage and is already being introduced into the production of MRI scanners together with the medical company Mediwise. The results of the work were published by the team in the current issue of the Advanced Materials journal.

MRI (magnetic resonance imaging) is one of the key methods of modern diagnostics, widely used in medicine, biology and neurology.An MRI scan allows you to track the subtlest physiological changes in internal organs. For example, a timely MRI scan can help identify areas of cancer at the earliest stage of the disease. The possibility of effective MRI diagnostics, however, directly depends on the quality of the images obtained.

A group of scientists from Russia, Australia and the Netherlands showed that the problem of image quality can be solved using a special substrate made of metamaterials – periodic structures that can interact with electromagnetic radiation in an unusual way.By placing such a substrate under the patient inside the MRI scanner, it is possible to significantly increase the signal-to-noise ratio in the scanned area, which leads to a huge increase in the resolution of the device and a reduction in scan time. In addition, the substrate allows you to suppress the electric field in the scanned area, which often leads to heating of the patient’s tissue, compromising the safety of the procedure.

Source: Advanced materials

The problem of heating living tissues has become even more urgent in connection with the recent arrival of high- and ultra-high-field scanners in medical practice.Thanks to the high-intensity fields, the resolution of these scanners is much higher than that of standard low-field devices. However, for the same reason, the possibility of heating living tissues in high- and ultra-high-field scanners also increases, so the question of the safety of this method remains open.

In the case of a substrate made of metamaterials, the scientists managed to completely avoid heating the tissues, while increasing the resolution. The proposed solution, in fact, does not require intervention in the hardware part of the MRI scanner and is an inexpensive functional attachment that can be used in any existing tomographs.

“Our metamaterial can be made not only in the form of a substrate, but also directly embedded in the patient’s table in an MRI scanner. However, we see the most interesting implementation of our invention in the concept of special “smart” clothes for MRI examination, – comments on the development of the first author of the article, a researcher of the laboratory “Applied Radiophysics” Aleksey Slobozhanyuk. – For example, strips of metamaterial can be imprinted on patient clothing.In such a vest, they will be able to undergo high-precision MRI examination, and the special design will allow uniform irradiation from all sides, which does not entail any risk to human health. As a result, by using metamaterials, you can improve the characteristics of low-field MRI in such a way that their functionality will be similar to high-field ones. ”

The time taken to obtain a standard MRI image is also a major inconvenience for patients today. In conventional MRI devices, scanning can last from 15 minutes to an hour, and during this entire period, the patient must lie still.Obtaining high-quality images in a shorter period of time will make the procedure more comfortable for the patient and, in the long term, even reduce the queues in hospitals.

“Our method of obtaining images of patient tissues with better detail in MRI scans will allow us to more clearly localize and study, for example, tumor diseases. According to the images obtained with the help of tomography, the surgeon determines the “pattern of the tumor”, which will later serve as a “stencil” for his scalpel during operation “, – summarizes Yuri Kivshar, one of the authors of the study, head of the Center for Nonlinear Physics at the Australian National University …

Scientists conducted their primary experiments on fish. Source: Advanced materials

The study involved scientists from ITMO University, Australian National University, Physics and Technology Institute. AF Ioffe, University Medical Center Utrecht in the Netherlands and the Institute of Experimental Medicine, Russian Academy of Medical Sciences.

Article: “Enhancement of Magnetic Resonance Imaging with Metasurfaces”, Alexey P. Slobozhanyuk, Alexander N. Poddubny, et al. Advanced Materials, Jan.11, 2016

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90,000 MRI with contrast

The scanning capabilities of a modern tomograph are very high, but in some pathologies, standard MRI is not enough to solve research problems.To carry out high-quality and reliable diagnostics in such situations, additional contrasting allows. It consists in the intravenous administration of special staining solutions to the patient before or during the scanning process.

Once in the body, the solution “illuminates” the vessels. Due to this, pathological foci and formations are seen more clearly, the degree of development of pathology is determined even at the earliest stages. Without contrast, much is simply impossible, for example, to see a number of specific brain tumors.

Readings

MRI with contrast is not prescribed for everyone in a row – a conventional scan can cope with most tasks, but only according to indications:

If there is a suspicion of tumor processes in bone and soft tissues;

· To determine the boundaries of the tumor and its structure;

· To identify metastases, the depth of their germination and the level of supply of blood vessels;

· To assess the activity of multiple sclerosis foci;

· For control in the postoperative period.

According to statistics, studies with contrast account for approximately 25% of all MRI scans.

Can a radiologist prescribe contrast enhancement?

A referral for contrast-enhanced magnetic resonance imaging is usually obtained from a treating physician. But the radiologist of the MRI center can also order the study, who noted something alarming with a simple scan.

Any suspicion of a volumetric or focal process by the radiologist is a sufficient basis for a contrast study.

What if the attending physician and the radiologist had a disagreement over contrast? In such situations, we recommend that patients obtain an independent opinion by contacting one or two doctors. It is advisable that they specialize in the problem seen by the radiologist.

About the safety of MRI with contrast

Modern drugs are not toxic, they are quickly excreted from the body. In medicine, a great deal of experience has been accumulated in the use of coloring solutions, which speaks of their harmlessness.Only in 0.1% of cases contrasting can give temporary side effects: skin rash, headaches, dizziness. The Moscow MRI Centers use the gadolinium-based Omniscan, a hypoallergenic drug, which reduces the risk of unpleasant consequences to zero.

Contraindications for MRI with contrast are minimal. The study is not prescribed for individual intolerance to the drug, during pregnancy and lactation.

90,000 indications, contraindications and the objective need for a contrast medium with MRI

whole list

As a rule, the method of magnetic resonance imaging is quite informative.However, sometimes the patient is given a contrast-enhanced MRI. This is a detailed study that allows you to assess the structure of tissues and cells of the body.

This diagnostic method is most often prescribed to cancer patients for a detailed study of the tumor and the extent of its spread. In oncology, contrast-enhanced MRI can significantly increase the information content of the procedure. A contrast agent injected into a vein during MRI allows detecting a tumor at the very initial stage of its development, clearly identifying the boundaries of a malignant tumor, its structure and consistency.

Substances for research

The substance used for contrast-enhanced MRI is significantly different from the drugs used for conventional magnetic resonance imaging. For an expanded MRI with contrast, the patient is injected intravenously with one of the drugs based on the gadolinium metal:

• Magnevist;
• Omniscan;
• Gadovist;
• Dotarem.

The contrast agent is administered intravenously, using a syringe or injector, carefully calculating the dose and rate of administration of the drug.The contrast agent delivery is synchronized with the progress of the MRI scan.

When is it necessary to have an MRI scanned?

Readings:

• The period of rehabilitation after removal of herniated intervertebral discs – for the differential diagnosis of scar tissue from recurrence of the disease.
• Suspicion of a benign pituitary mass, whereas conventional magnetic resonance imaging does not detect a tumor.
• Using MRI with contrast, you can determine the degree of activity of multiple sclerosis, as well as judge the effectiveness of the therapy.
• For malignant and benign neoplasms in the brain and spinal cord. Sometimes native MRI does not provide enough information about the boundaries and consistency of the neoplasm. As a result, the doctor cannot diagnose and prescribe the correct treatment for the patient. In this case, MRI with contrast is prescribed. Thanks to a detailed and detailed study, the doctor can determine the size of the neoplasm, the place of its localization, the borders of the tumor and its consistency.
• MRI with a contrast agent allows to assess the state of the structures of the brain and spinal cord after surgery. During the study, the doctor notes whether there is a relapse of the disease in a given patient.
• For the detection of metastases in the spinal cord and brain. Due to the small size of metastases, the doctor finds it difficult to identify them, and the MRI method with the introduction of a contrast agent allows you to detect metastases at an early stage of their formation.

When shouldn’t MRI with contrast be done?

Contraindications:

• Pregnancy at any time;
• Breastfeeding the baby.

Possibility of allergic reactions

Patients with an allergic predisposition to drugs are often worried about possible complications after the administration of a contrast medium. Due to the fact that the preparations used for contrasting do not contain iodine, allergic reactions are practically not observed.The above drugs for MRI with contrast are non-toxic, therefore they are well tolerated by patients, even allergy sufferers, and do not cause side effects after being introduced into the body.

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90,000 Examination using MRI with contrast

One
of the most modern types of research is
magnetic resonance imaging (MRI)
with the use of contrasting. This is a method that allows you to get detailed
the image of almost any organs and tissues of the human body.

C
using magnetic resonance imaging, you can study the slightest
changes
abdominal organs,
as well as pathologies and malfunctions
brain.

MRI produces layered images
organs, then, using a special computer program, creates a volumetric
model of the investigated organ. So
by means of research, the doctor has the opportunity to assess the dynamics of the disease,
see what processes are taking place in the organs and systems of the patient.To the most important
The advantages of MRI diagnostics include:

• high resolution images and
  images;
• No overlay effects like
  with radiography;
• the ability to observe the dynamics of changes
  in organs over time;
• non-invasiveness of the study, no
  damage from manipulation;
• no radiation hazard for
  the patient, as in an X-ray examination.

If you are worried about a health problem, make an appointment for a diagnosis. The success of treatment depends on the correct diagnosis.

Preparation and conduct of magnetic resonance imaging

Special training
MRI examination is usually not required, unless
for more informational content of the study, the doctor may prescribe the introduction
contrast agent that allows you to see the examined part of the body or
body more clearly.Preparation for MRI with contrast may not always be required and depends on the area of ​​interest. When examining the abdominal cavity a few days before the study, products that increase gas formation should be excluded from the diet and 5-6 hours before the procedure, refrain from taking food and liquids. And to diagnose the pelvic organs, you will need to fill the bladder and take a lubricant.

How is MRI with contrast done?

B
contrast quality most often
use gadolinium, which dissolves
in water.Gadolinium salts are less toxic
in comparison with other contrasting
fluids currently in use.

Contrast
the fluid is injected intravenously, passes through
vessels and accumulates
in the examined soft tissues. Thanks to this accumulation, more
informative visualization of tissue or organ. Features of the composition of gadolinium
make it possible to amplify and accelerate the electromagnetic pulse at
conducting MRI, which has a very positive effect on the information content
received images.

Another method of administering contrast
substance is the so-called bolus
contrasting. In this case, the liquid is introduced into
vein with a dropper.

At
by bolus contrast, the accumulation of substance in the tissues
occurs gradually and synchronizes with scanning. This way of research
on MRI is called dynamic magnetic resonance imaging. Introduction
the substance is used to study many pathologies, but it is necessary
used to diagnose diseases such as:

• oncological neoplasms
  internal organs and
  soft tissues;
• multiple sclerosis.For more accurate
  studies of the affected areas of the brain and determining the degree of their damage.

Use
magnetic resonance imaging with the introduction of contrast helps to detect many different neoplasms in
brain.
Contrast-enhanced MRI of the brain is prescribed to diagnose disorders
and brain pathologies, degenerative changes.

MRI with and without contrast – what
difference? Why is MRI done with contrast?

Conducting MRI
with contrasting is necessary when
you need to distinguish a malignant tumor from a simple cyst or benign
tumors.In such cases, MRI without the use of
contrast much less
informative.

How often can an MRI with contrast be done?

The frequency of diagnostics should be determined by the presence of appropriate indications and depends on the nature of the pathology. The procedure can be performed as often as required by the diagnosis and effective treatment.

Contraindications for MRI with contrast

Contraindications
for
conducting magnetic resonance
examinations (MRI) using a contrast medium are almost identical with
contraindications for MRI without it.