|body part||MRI with contrast medium||non-contrast MRI||MRI with or without contrast|
|Brain||Gamma knife surgery||Alzheimer's disease Headache/migraine Memory loss Seizures Stroke Trauma||infectionsmetastatic cancerMultiple sclerosisneurofibromatosispituitary|
|columna cervical||Disc degeneration Herniated disc Neck painradiculopathyTrauma||Disc infection Mass/lesionsOsteomyelitis|
|thoracic spine||Back pain Disc compression Herniated disc Radiculopathy Trauma||Disc infection Mass/lesions Osteomyelitis|
|lumbar spine||Back pain Disc compression Herniated disc RadiculopathyStenosisTrauma||Disc infection Mass/lesions Osteomyelitis Post-lumbar surgery|
|extremities (not together)||fractures muscle tear tendon tear||abscesses cellulitisOsteomyelitis tumors/massive ulcers|
|joints||Direct arthrography of a joint (given by injection into the joint)||Arthritis cartilage tear fracture joint painmeniscus tearmuscle tear tendon tear||Abscesses Cellulitis Osteomyelitis Tumor/massive ulcers|
|pool||Pelvic pain Muscle rupture Tendon ruptureSanto/coccyxSacroiliac joint abnormality of the uterusendometriosisproblems with menstruation||Abscesses Ulcers Osteomyelitisovarian cysts known fibroids fibroid embolism|
|Abdomen||Kidney glands||Kidney-liver tumor/mass|
As the guidelines illustrate, the decision to use or not to use contrast media is largely subjective and depends on the judgment and experience of the health care provider.
How are MRIs used in orthopedics?
Types of Contrast Agents
Most contrast media used contain a rare metal called gadolinium, which interacts with the magnetic field generated by the MRI machine. Gadolinium-based contrast agents (GBCA) come in several types, distinguished by:
- Chemical composition
- magnetic properties
- How they are distributed throughout the body.
- How they are administered
Some GBCAs are organ-specific, while others have a higher molecular weight, allowing them to remain in the circulatory system and not spread to adjacent tissues. Others still can target specific cells, such as tumors.
A GBCA is not always useful. For example, gadolinium cannot easily pass through them.blood brain barrier(BBB), which protects the brain from pollutants.While useful for diagnosing diseases with an altered BBB, such asMultiple sclerosis, GBCAs are not as useful if the barrier is intact.
MRI contrast agents licensed by the US Food and Drug Administration (FDA) approved for use include:
- Dotarem (Gadoterat-Meglumin)
- Evoist (Gadoxetat-Dinatrium)
- Gadavist (Gadobutrol)
- Magnevista (Gadopentetate-Dimeglumine)
- Multihance (Gadobenato-Dimeglumina)
- Omniscan (Gadodiamida)
- OptiMARK (gadoversetamide)
- Prohance (Gadoteridol)
Before the test
An MRI is performed by an MRI (also known as a radiologist or radiology technologist) and interpreted by a radiologist.
A contrast-enhanced MRI can take anywhere from 30 to 90 minutes, depending on the region of the body being examined, the agent used, and the route of GBCA administration.
Oral GBCA MRIs can take up to two and a half hours, requiring you to drink several doses and wait for the medication to enter the intestines.
Be sure to arrive 15-30 minutes before your appointment to complete the required paperwork and get settled.
MRIs are performed in outpatient MRI clinics and in hospitals.
The MRI machine will be installed in a dedicated room within the facility. After you are placed in the machine, the radiology technologist operates the machine behind a glass partition. You can communicate through a two-way speaker system inside the device.
The MRI machine itself is a tubular device into which a flatbed is inserted and removed by remote control. Some smaller units only allow you to insert one arm or one leg.
Many newer models are open on the sides, which reduces the claustrophobia some people feel when scanning.
what to wear
Because MRI uses strong magnetic fields, you should not wear anything that contains metal during the procedure, including:
- metallic buttons
- underwire bras
It is best to leave jewelry at home and remove metal accessories such as piercings and hairpieces from your body.
You will be given a change of clothing if your clothing interferes with the MRI readings. Some people come with their own clothing, such as B. Drawstring pants, sweatpants, plain T-shirts, or sportswear. To avoid going barefoot, bring socks or a pair of slippers.
Dentures and hearing aids must be removed before the procedure. The medical staff will provide you with a safe place to store your belongings.
eat and drink
For GBCAs given by injection or intravenously, you can usually eat, drink, and take your medications as usual. The same is not true for oral GBCAs, which may require you to stop eating and drinking four or more hours in advance.
The radiology staff will inform you if there are any dietary or medication restrictions for your procedure.
Expense and health insurance
Contrast-enhanced MRIs can cost anywhere from $300 to $3,000, depending on the part of the body being scanned and its location.
However, many health insurance companies cover at least part of the costs.priority clearancemake sure it is medically necessary.
Coverage levels can vary by plan, so do your research.copayment or coinsuranceCosts before the procedure and confirm that the radiology unitYRadiologists are bothprovider on the web.
Be sure to bring your photo ID and insurance card, as well as an approved form of payment for any copay/coinsurance charges. If you plan to wear small jewelry in there, you may want to bring a bag to store it in.
Tell the radiology staff ahead of time if you:
- a metal implant
- drug infusion pump
- artificial limbs or joints
- metallic ink tattoos
Although many of these are MRI-safe, they can potentially interfere with the measurement.
Inform the staff if you are pregnant.
if you haveclaustrophobiaPlease inform the staff in time. In some cases, you may be able to take a mild sedative. If one is used, you will need to arrange for someone to drive you home after the procedure.
How an MRI with Contrast is Performed
For a contrast-enhanced MRI, you'll work with a technician certified in the administration of intravenous, oral, and intra-articular GBCAs.
Qualified technicians can also administer sedation, although a nurse may also be available to do so.
After completing the required paperwork and signing a consent form, you will be taken to a locker room where you can change into a hospital gown (if necessary).
Before the MRI, the technician or nurse will check your weight, height, heart rate, temperature, and blood pressure. The technician will then prepare you for the scan in several ways.
If the GBCA is intravenous, an IV catheter will be placed in a vein (usually in the arm).
You may feel a sharp sting and a temporary chill while GBCA is being administered, but otherwise you should feel little pain. If it hurts, tell the technician.
Atranquilizersit can also be administered through a portal in the catheter if needed.
If GBCA is given orally, you will be given one or more doses of the medication to drink. Some have a berry flavor, while others have a sweet and syrupy taste.
Some people develop a metallic taste in their mouth or feel like using the bathroom after drinking the solution. That is normal. However, if you feel nauseated or have a stomach ache, tell the technician right away.
If the GBCA is administered intra-articularly, the radiologist may use a topical anesthetic before giving the injection. In some cases, excess synovial fluid must be removed througharthrocentesis.
During the injection, you may feel pressure or pain around the injection site along with a temporary sensation of coldness. The injection usually takes 30 seconds to a minute.
Use of gadolinium in magnetic resonance imaging of breast cancer
throughout the test
After the GBCA is delivered, you will be guided to the MRI flatbed and strapped in to prevent movement.
A cage-type headrest can be used for MRIs of the head. Depending on the level of sedation used, breathing, heart rate, blood oxygen, and blood pressure may be monitored during the procedure, especially in children.
You may also be provided with noise-canceling headphones to communicate with the technician.
The MRI itself can take anywhere from 15 minutes to an hour. To ensure the best image quality, follow the technician's instructions and remain absolutely still until told to relax. You may also need to hold your breath during parts of the scan.
It is not uncommon to feel a little warm during the scan. You should also be prepared to hear a loud noise with each recording, described by some as a locomotive. However, newer machines are much quieter.
If you are unable to hold a position, have cramps, or suddenly feel nauseated, tell the technician. It's no problem to stop and rest until you're ready to continue.
Once the technician has completed the requested scans, the images are reviewed to ensure that they are all clear and in the correct position. In some cases, it may be necessary to repeat part of the scan.
Head and Brain MRI: What to Expect
If a sedative was not used, you can usually get dressed and leave right away. The technician or nurse may want to check that you are not experiencing any adverse effects before allowing you to leave.
If a sedative was used, you will be taken to a recovery room and monitored until you can sit up safely. As soon as you can stand up, someone has to take you home. Ideally, this person will stay with you for 24 hours in case of an unexpected side effect.
In most cases, an MRI with contrast media has no immediate or lasting effects. Still, it's important to call your doctor right away if you have unusual or severe symptoms, including:
- abnormal heartbeat
- difficulty breathing
- Severe pain, redness, swelling, or discharge at the injection site
If you are breastfeeding, some health care providers tell you to wait 24 to 48 hours before breastfeeding your baby. However, the American College of Obstetricians and Gynecologists (ACOG) says that it is unnecessary and that you can continue breastfeeding without interruption after an MRI with contrast.
MRIs with contrast scans are interpreted by a radiologist who reviews findings related to previous scans and your available medical history. He will then issue a radiology report within a few days, which your doctor will discuss with you.
A typical radiology report includes a copy of each individual scan along with notes on any abnormalities noted. Typically, each image is categorized roughly as follows:
- Not normal
Specific details are given in theimpressionsSection of the report that your health care provider can explain to you.
Based on an evaluation of the scans and a review of your medical history, the radiologist can offer a specific diagnosis or a list of possible causes all at once.differential diagnosis.
If the findings are abnormal or potentially abnormal, you may be referred for additional imaging tests or procedures to confirm the diagnosis or determine the severity of the condition.
For example, a growth suspected of being cancerous may require aPositron emission tomography (PET)Scan that can identify malignancies based on changes in metabolism, or aBiopsy, in which a sample of tissue is taken for examination by apathologist.
If a finding is inconclusive, the MRI may be repeated or an alternate imaging modality may be used. For example, CT scans are often better for imaging bone diseases than MRIs, which are better for imaging soft tissue.
MRT vs. computed tomography
Risks and contraindications
GBCAs are generally considered safe with relatively few side effects. When side effects do occur, they are usually temporary and go away on their own without treatment. In rare cases, complications or serious side effects can occur in certain groups of people, including people with kidney problems.
The long-term cumulative effects of GBCAs are unknown. For this reason, your health care provider may limit the number of MRIs you receive with contrast media or MRIs with other imaging tests, such as x-rays or interspersed tests.Computed Tomography (CT)scans
X-ray Safety and Risks
IV Side Effects
GBCAs are most often given through an intravenous (IV) infusion into a vein. The most common side effects of GBCA infusions are:
- Cold sensation during injection.
- To vomit
- fast heartbeat
- difficulty breathing
Although rare, some people may experience a mild allergic reaction to gadolinium. The main symptom isskin itch, and the allergy itself is rarely serious.
A study published inbritish journal of radiologyreported that between 0.18% and 0.76% of people who undergo an MRI with contrast media experience side effects, primarily nausea and vomiting.
oral side effects
Oral GBCAs are sometimes used for MRIs of the GI tract. You swallow them in liquid form before the scan. The contrast agent typically includes a form of gadolinium (known as gadolinium-DPTA) mixed with mannitol (a type ofsugar alcoholpoorly absorbed by the intestine).
Mannitol is known to cause nausea, vomiting, and diarrhea in some people. Although gadolinium can be used on its own with few or no gastrointestinal side effects, it requires mannitol to remain stable in the acidic environment of the stomach and intestines.
Intra-articular side effects
Arthrography is an MRI technique used to visualize joints when a standard MRI does not provide enough detail.Arthrography requires an intra-articular injection of GBCA into the joint space.
The injection itself can cause localized pressure and pain. There may also be slight swelling after the procedure, which can usually be treated.ice application. Redness and bruising may also occur at the injection site.
rare side effects
In rare cases, certain GBCAs are known to cause a serious condition called nephrogenic systemic fibrosis (NSF) in people with severe kidney disease.
NSF can cause similar stretching and hardening of the skin.scleroderma, as well as the contraction of tendons and muscles that affect the movement and mobility of the joints. The function of certain organs such as the heart, lungs, diaphragm, stomach, intestines, or liver may also be affected.
NSF has no cure, and no known treatment provides consistent results. For this reason, GBCAs should be used with extreme caution in people with impaired kidney function and should be avoided in people with severe kidney function.chronic kidney disease,acute kidney injury, the enDialysis.
long term security
Debate continues about the long-term safety of GBCAs, particularly when used extensively or regularly (eg,Multiple sclerosis monitoring).
In 2015, the FDA issued a safety advisory citing studies in which long-term use of gadolinium in people with MS resulted in deposits of the material in brain tissue.
Recent research indicates that the risk of accumulation is dose dependent, i. h The longer gadolinium is used, the greater the risk.For people who have been exposed to GBCA only one or more times, the risk appears to be negligible.
What the FDA recommendation did not say is whether the deposits posed any health risks. Although some scientists have suggested that the accumulations could cause neurotoxicity (poisoning of the brain), the evidence for this is scant.
A 2017 review of studies inlancet neurologyconcluded that no damage or behavioral changes were observed in animals exposed to high doses of gadolinium over a long period of time. The few human studies have also shown no negative effects.
Despite the conclusions, the researchers would not go so far as to say that accumulating gadoliniumNeverCause trouble. Rather, they suggested that more research is needed before gadolinium can be considered empirically safe.
Safety of contrast dyes used in imaging
A word from Verywell
When a healthcare provider recommends an MRI with contrast, it's not unreasonable to wonder if the contrast agent is really necessary. There may be reasons why contrast is needed, but it's fair to ask if there are other options.
This is especially true if you have known kidney disease or have had multiple MRIs with contrast media. If you have doubts, do not hesitate to look for one.second opinion.
What is a functional MRI?
How long after an MRI would I have side effects from the contrast agent?
Reactions to contrast media are usually immediate and range from mild symptoms, such as rash, hives, vomiting, dizziness, and runny nose, to severe symptoms that can include a life-threatening heart attack. However, in up to 23% of patients, these symptoms appear as a delayed reaction, occurring 6 to 12 hours after injection or ingestion of the contrast medium.
Learn more:Signs of a severe allergic reaction
How long does it take for the contrast dye to leave the body?
If you have normal kidney function, the contrast dye should leave your body within 24 hours of the test. The contrast medium is processed by the kidneys and eliminated from the body in urination.
What is the difference between an MRI with and without contrast medium?
Both are scans that use magnetic and radio waves to take pictures inside your body. For an MRI with contrast dye, contrast dye is injected into your veins or taken by mouth. This tint highlights certain tissues in your body, allowing for more detail in the image.It is useful for obtaining information on specific types of disorders.
Learn more:MRIs and breast exams
Is the contrast medium used in MRIs dangerous?
Although the risk of side effects and allergic reactions is low, gadolinium, the contrast agent used in MRIs, is considered safe for most people. However, an MRI with contrast dye can cause serious problems for pregnant women and people with kidney disease.Prolonged or frequent exposure to gadolinium is not well understood, but it can also lead to complications.
Learn more:What you should know about kidney disease(Video) What to Expect from an MRI Exam with Contrast