Spine MRI: Why and How It's Done

A spine MRI, or magnetic resonance imaging, uses powerful magnets, radio waves, and a computer to make very clear and detailed pictures of your spine.

You may need this scan to check for spine problems, including:

The MRI may scan your whole spine or just a part of it. Unlike X-rays and CT scans, it doesn’t use damaging radiation.

Why Might You Need It?

The MRI lets your doctor examine the small bones, called vertebrae, which make up your spinal column, as well as the spinal disks, spinal canal, and spinal cord. The test looks for:

Unusual parts or curves in your spine

  • Fractures in the vertebrae
  • Injuries
  • Infection
  • Swelling
  • Spinal cord problems
  • Bulging or slipped spinal disks
  • Tumors

Your doctor may also use a spine MRI to help plan surgeries on the spine, like for a pinched nerve, or for procedures like epidural or steroid shots.

How Do I Prepare for the Scan?

Usually, you can eat, drink, and take medication as you normally do before the procedure. You may wear a gown, or your own clothes if they’re loose and don’t have any metal. You would need to take off any eyeglasses, hearing aids, jewelry, your watch, and other items.

Let your doctor know if you:

  • Have any serious health problems, such as kidney or liver disease
  • Recently had surgery
  • Have any allergies or asthma
  • Are pregnant, or think you may be
  • Wear a medicine patch

Metal and electronics may affect your MRI image or attract the magnet. You won’t be able to get a scan if you have metal inside you, including:

  • Artificial heart valve, limb, or joint
  • Clips to treat a brain aneurysm
  • Cochlear (ear) implant
  • Implanted pump, such as a drug or insulin pump
  • Metal fragments, such as bullets or shrapnel
  • Metals pin, screw, plate, stent or surgical staple
  • Pacemaker or defibrillator

If you have tattoos or permanent makeup, talk with your doctor. Some inks contain iron that could heat up during the test.

If you don’t like being cooped up in small spaces or you’re nervous about the test, tell your doctor. You may get medicine to relax you beforehand.


What's the Equipment Like?

An MRI machine is a long, narrow tube with both ends open. A magnet surrounds the tube. You lie on a table that slides into the tube.

Some MRI machines have much larger openings or are open on the sides so you don’t have to slide into a tube. They may be a good choice if you are overweight or fear tight spaces. Your doctor will decide which MRI machine will work best for you.

The Scan

Before some MRIs, you might need a dye injected into a vein in your arm or hand. It helps the doctor more clearly see any infection, tumor, or disk problem in your spine. The dye often used in MRIs is called gadolinium. You might feel flush or cold for a few moments afterward. It can also leave a salty or metal taste in your mouth.

You’ll lie on the table that slides into the MRI machine. Straps may be used to help keep you in the right position during the test. A radiologist and technologist will be at a computer, outside of the room. They can see, hear, and talk to you the whole time. Sometimes your family or friend can stay in the room with you.

Often an MRI exam includes a number of runs, or sequences. Each run can last from a few seconds to several minutes long. You have to stay very still during each one.

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

You won’t feel any pain during the test. But you may feel warmth in the area of your spine being scanned. You’ll also hear a loud tapping or thumping when the image is being recorded. Earplugs or headsets can help block out the noise if it bothers you. You can even listen to music.

MRI scans can take from 30 minutes to an hour or more, depending on how much of your spine is being scanned.

After a spine MRI, you can go back to your normal activities right away. But if you needed medicine to relax before the test, you’ll need to wait until it wears off.

Sometimes contrast dye can cause side effects. You might feel nauseated or have a headache, or you might have some pain where the dye was injected. An allergic reaction to the dye is rare. But if you get hives, itchy eyes, or any other symptoms, tell your radiologist right away.


Your Results

A specially trained doctor called a radiologist will look over your spine MRI and report the results to your doctor. Your doctor will explain what they mean and what to do next.

WebMD Medical Reference Reviewed by Tyler Wheeler, MD on February 06, 2018



Radiological Society of North America: “Magnetic Resonance Imaging (MRI) -- Spine.”

North American Spine Society: “Magnetic Resonance Imaging (MRI).”

Johns Hopkins Medicine: “Magnetic Resonance Imaging (MRI) of the Spine and Brain.”

Mayo Clinic: “MRI.”

American College of Radiology Imaging Network: “About MRI Scans.”

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