Magnetic resonance imaging (MRI) is a safe, painless test that uses radio waves and energy from strong magnets to create detailed images of the body. A cervical MRI scans the soft tissues of the neck and the cervical spine. The cervical spine is the portion of the spine that runs through the neck.
A cervical spine MRI is used to help diagnose:
- tumors in the bones or soft tissues
- bulging (herniated) discs
- aneurysms (bulges in arteries) or other vascular disorders
- other soft tissue disorders, bone abnormalities, or joint disorders
An individual MRI image is called a “slice.” It’s an image of a cross-section of tissue. You can think of it in the same way a slice of bread is a cross-section of a loaf of bread. One complete MRI scan can consist of hundreds of slices. These images can be stored on a computer and then converted into 3-D images of the scanned area.
An MRI scan uses a powerful magnetic field and radio waves to take detailed, 3-D pictures of the body.
The human body is 80 percent water, so it contains millions of hydrogen atoms. When these atoms come into contact with the MRI’s magnetic field, they all line up in the same direction. The radio waves the MRI produces disrupt this alignment when they’re added to the magnetic field.
After the radiofrequency is turned off, the atoms return to their original position. How long this takes depends on the type of tissue. A sensor in the MRI machine calculates how long it takes for the atoms to realign with the magnetic field. The results are translated into images.
In some cases, contrast dye is injected intravenously (through a vein) before the MRI. This can make it easier to see blood vessels and tumors in better detail. An MRI using contrast dye is called a magnetic resonance angiogram (MRA).
A cervical spine MRI is usually used to diagnose the cause of neck pain. It’s often performed if the pain hasn’t improved with basic treatment. It may also be done if the pain is accompanied by numbness or weakness.
A cervical MRI scan can show:
- spinal birth defects or deformities
- an infection in or near the spine
- injury or trauma to the spine
- scoliosis (curvature) of the spine
- cancer or tumors of the spine
A cervical MRI may also be ordered before or after spinal surgery.
Ask your doctor if you can eat or drink before the scan, as protocols vary between facilities. Tell your doctor if you have diabetes or kidney problems if your MRI includes a contrast dye. You may need a kidney function test before the scan. This will ensure that your kidneys can process the dye safely.
Tell your doctor if you’re pregnant. MRIs are not recommended during the first trimester of pregnancy. Your doctor may choose to postpone the scan until after you’ve had your baby.
Tell your doctor if you’re claustrophobic or have a fear of being in enclosed spaces. They can prescribe an antianxiety medication to make you more comfortable during the test. In some cases, you may be given anesthesia to put you to sleep.
Tell your doctor about any metal implants you have from a previous surgery. It may not be safe for you to have an MRI scan.
Bring any relevant X-rays, CT scans, or previous MRI scans with you to your appointment. Sometimes the MRI technician will play music to help you relax. Bring a CD with you just in case.
Before you go in for the MRI, you’ll need to remove all jewelry and clothing that contains metal. It may be easier to leave your jewelry at home. You’ll probably need to wear a hospital gown during the test.
Your doctor might recommend an open MRI if you’re overweight or extremely claustrophobic. Open MRIs have slightly larger openings than standard machines. However, open MRIs aren’t available at all hospitals or clinics, so check with your doctor beforehand.
You’ll lie down on a narrow bed that’s attached to the MRI machine. Your head will be on a headrest and your arms will be at your sides.
The MRI technician will give you earplugs to muffle the loud knocking and thumping noises the machine makes when it’s running. You may have the option to listen to music during the scan. This can help relax you and distract you from the noise.
A frame called a “coil” will be placed over your head and neck. The coil contains an antenna. It helps focus the machine’s energy so it produces the most precise images. The MRI technician will also place a signaling device in your hand. You can use it to call for help while the test is running, if you need it.
Once you’re properly positioned, the table will slide into the machine. The MRI technician will be able to see you through a window in an adjoining room. They’ll give you periodic updates on the scan’s progress.
Cervical MRI scans typically take 30 to 45 minutes. During this time, it’s very important that you stay as still as possible. The images may be blurred if you move.
Once the images are produced, they’ll be given to a radiologist. A radiologist is someone who specializes in interpreting MRI scans. The radiologist will then give the results to your doctor, who will go over them with you and explain what they mean.
MRI scans are very safe. They don’t use any form of radiation. The magnetic field and radio waves don’t pose any known health risks.
Some people may have an allergic reaction to the contrast dye used during an MRI. Tell your doctor if you’ve had a prior reaction to injected dyes. You should also let them know if you have a shellfish allergy.
The magnetic field the MRI scanner produces is extremely powerful. It will interact with any metal in or on your body. Tell your doctor if you have:
- an implant, such as a metal plate or screws
- a cardiac pacemaker
- metallic piercings or studs
- an intrauterine device (IUD) that contains metal
- a drug-delivery device, such as an insulin pump
- aneurysm clips
- a lodged bullet or piece of shrapnel
- a cochlear implant
- permanent (tattooed) make-up
You may not be able to have a cervical spine MRI if you have metal in your body or you’re pregnant. Your doctor may order a bone scan, CT scan, or additional X-rays instead.