Key takeaways:
- Both MRI with and without contrast are non-invasive and painless.
- Contrast MRIs use a contrast dye such as gadolinium, while non-contrast MRIs don’t.
- A contrast MRI scan is safe for patients who aren’t pregnant and don’t have pre-existing medical conditions like kidney abnormalities, though alternative options may be available.
- Slight side effects such as dizziness, nausea, vomiting, pain at the injection site, and skin rashes are associated with contrast MRIs. They usually wear off within an hour or so.
- Standard radiology specialty centers like Ezra can assist patients needing MRI with or without contrast imaging.
The World Health Organization estimates that 30 to 50% of cancers are preventable. Part of this is due to early detection1.
Companies like Ezra can help you get screened without a physician’s advice and stay on top of your health. MRIs (magnetic resonance imaging) with and without contrast can help you detect cancer early so you can act early.
An MRI uses magnets and radio waves to create detailed images of your body’s organs and structures2. Radiologists then use these images to detect possible issues such as cancer.
This scan can detect medical conditions in different parts of your body, such as the brain, heart, blood vessels, bones, breasts, liver, kidneys, pancreas, ovaries (in women), and prostate (in men). MRI is especially useful for looking at soft tissues within these body parts2.
An MRI scan can help you diagnose a disease or injury. It can also monitor your response to treatments for tumors, cirrhosis (diseases of the liver), etc. Unlike CT (computed tomography) scans and X-rays, MRIs do not use radiation3.
Types of Scans: MRI With and Without Contrast
There are two types of MRI imaging: MRIs with and without contrast. A contrast agent is a liquid injected into the body to make certain tissues clearly visible during the imaging process.
Contrast MRI
When you undergo a contrast MRI, you will be administered a contrast agent such as gadolinium intravenously (injected into your veins). It will help your radiologist gain deeper insights into how your body is working to identify an abnormality or disease4.
For instance, a non-contrast imaging test is as capable as a contrast MRI in diagnosing a stroke. However, with a gadolinium-based agent, your physician can distinguish between transient ischemic attack (TIA) (a brief stroke), thrombosis (a blood clot in the circulatory system), and venous insufficiency (a condition in which the veins in the legs fail to pump blood back to the heart)5–7. So, a contrast MRI can give details that a non-contrast MRI can’t provide.
Possible medical diagnoses from contrast MRIs include cancer, pituitary disease, vascular malformations, central nervous system aneurysms, acoustic neuromas, and the underlying causes of seizure2,8.
Non-Contrast MRI
A non-contrast MRI is also an effective exam for imaging your body’s organs. Though it doesn’t use contrast dye, it can still be quite accurate.
Contrast vs Non-Contrast MRI
Let’s review how a contrast MRI is different from a non-contrast one.
- A contrast MRI uses a contrast agent, while non-contrast MRIs don’t. As a result, the latter may require additional follow-up procedures to clarify abnormalities.
- Contrast MRIs tend to be easier to interpret than non-contrast MRIs.
- Contrast MRI can detect smaller tumors9.
- Contrast MRIs take longer to perform than non-contrast MRIs. The time taken varies depending on the area of the body being scanned. For example, a 45-minute procedure to assess the brain and spine becomes a 1-hour procedure with contrast agents10.
When a Contrast MRI Might Be Preferred
With contrast MRI, it’s easier to see which areas of the body may have issues. That’s because the abnormal tissue will stand out more than in a non-contrast MRI. Your medical practitioner may suggest a contrast MRI based on your present condition and your medical and health history.
When a radiologist injects a contrast dye into your veins or directly into a joint (an arthrogram11), it enhances the visibility of inflammation, tumors, blood vessels, and the blood supply to certain organs.
Because of potential side effects, you should only undergo a contrast MRI after consulting your physician. Contrast MRI is typically not recommended for most sports or spine injuries, but it can be beneficial in other situations.
For example, a doctor might not use contrast to detect a bone tumor or evaluate the extent of cancer spread. However, they may choose to use contrast to gain more information about tumor characteristics, such as determining whether a tumor is benign or malignant. In the case of soft tissue tumors, contrast can help assess their spread and provide a detailed characterization12.
Who Should Have a Non-Contrast MRI?
Non-contrast MRIs are especially recommended for pregnant women, patients with compromised kidney function, and anyone who can’t typically use contrast MRI medical imaging. However, modern contrast dyes may be suitable in some cases13.
Pregnant women are generally advised to take non-contrast MRIs unless their physician says otherwise. This is because gadolinium dye is associated with increased risks to the fetus14.
Your medical caregiver should only suggest you take a contrast MRI during your pregnancy if it is expected to improve the fetal and maternal outcome (ACOG)15.
Generally, non-contrast imaging is popular with most orthopedic studies since the imaging comes out clear without the contrast dye. However, the choice between contrast and non-contrast can depend on the type of disease and the precise medical question being asked12.
What can MRIs detect?
Here are common diseases and abnormalities that MRI scans help to discover throughout the body2,16:
MRI of the brain, head, and neck:
- Traumatic brain injury
- Brain tumors
- Stroke
- Infection
- Dementia
- Temporomandibular joint (TMJ)
- Multiple sclerosis
- Developmental anomalies
MRI of arteries and veins:
- Aneurysms
- Blood vessel blocks
- Arteriovenous malformations
- Carotid artery disease
MRI of the spine:
- Pinched nerves
- Herniated discs
- Fractures
- Spinal cord compression
- Spinal tumors
- Stenosis
MRI of the abdomen:
- Renal arterial obstruction (complete blockage of blood to the kidney)
- Renal vein thrombosis (acute kidney injury)
- Glomerulonephritis (a condition in which the glomeruli of the kidney become inflamed)
- Hydronephrosis (enlargement of the kidney from urinary reflux)
- Acute tubular necrosis (a kidney disorder in which the tubule cells get damaged, leading to acute kidney injury)
How Is Contrast MRI Performed?
To understand how contrast MRIs are performed, let's take a look at brain MRIs, which make use of contrast to find smaller tumors and enable tumor characterization9,17.
Before the scan, you’ll be asked about any allergies or health concerns regarding the use of the contrast agent. Whether you receive contrast or not, you will be asked to remove metal items such as jewelry, change into a comfortable gown, and lie still on a sliding table that enters the MRI machine. If you’re using a contrast agent, it will be administered with an intravenous catheter (IV line), which will be attached before the table enters the machine. You may experience discomfort or irritation at the injection site. Non-contrast images are typically taken before the contrast dye is administered. Besides the injection, the procedures for contrast and non-contrast MRIs are very similar4,18.
Potential Side Effects of Gadolinium Contrast
Gadolinium-based contrast agents are considered safe. And there is no clinical evidence of adverse health effects of gadolinium when given to most patients.
However, in a small percentage of patients, the dye could cause a few side effects such as:
1. Allergic Reactions
After a few minutes, one in a thousand patients might display minor allergic symptoms. Severe allergic reactions are extremely rare, affecting one in every ten thousand patients4.
The minor itchy skin rash usually wears off in an hour or so.
2. Pregnancy Risks
Gadolinium dye is associated with increased risks to the fetus14.
3. Nephrogenic Systemic Fibrosis (NSF)
NSF is a rare disease occurring in patients with pre-existing severe kidney function abnormalities. While contrast dye usually leaves a patient’s system quickly, those with kidney function issues might have trouble processing the dye19.
Therefore, if your healthcare provider recommends a contrast MRI for you or a family member with kidney issues, be sure to ask for and understand the reasons behind the recommendation.
4. Other Side Effects
A contrast injection can cause side effects like headaches, dizziness, nausea, and pain at the injection spot18. Those with allergies or kidney problems may experience additional symptoms.
Safety of contrast MRIs
Gadolinium can remain in the body, raising safety concerns. Studies are underway to evaluate these dyes' effects on long-term health20,21. However, several gadolinium-based contrast agents are approved for use by the FDA8,22.
Talk to your health practitioner about whether a contrast MRI is right for you.
How To Prepare for an MRI With or Without Contrast
Now that you know the differences between an MRI with and without contrast, let’s see how you could prepare to get your screening.
- Remove all metal jewelry, and let your practitioner know about any metal implants or pacemakers.
- If you are claustrophobic, let your radiologist know so they can give you a sedative. However, you won’t be able to drive yourself home.
- During the scan, lie still. Movements could blur the imaging results16. But don’t worry — you can chat with your radiologist over an intercom, and they can see you through a television monitor.
- Fasting is usually not needed before an MRI scan, but doctors may advise it in some circumstances. When a contrast agent is used, fasting may be recommended because contrast agents can cause nausea and vomiting, which can lead to complications while lying still during the procedure.
Schedule an Appointment for Your MRI Without Contrast With ezra
Deciding on a provider for your scan can be challenging. It’s important to research the accuracy of the scans provided, the costs, and the satisfaction of previous customers. Taking these factors into account will help you make an informed decision.
If there’s one thing we have found at Ezra, it’s that early detection is key to beating cancer, aneurysms, or other diseases.
We offer the quickest and most affordable full-body MRI service that screens for potential cancer in up to 13 organs. With Ezra, it can take up to an hour for a full-body scan, but once our AI technology is cleared by the FDA, this would come down to 30 minutes. And our MRI is radiation-free.
You deserve to live a long and healthy life, which is why it’s important to get annual full-body screening. Book an Ezra Full Body today.
