Magnetic resonance imaging (MRI) of the cervical spine is a safe and painless test that uses a magnetic field and radio waves to produce detailed images of the cervical spine (the bones in the back of the neck).
An MRI differs from a CAT scan (also called CT scan or a a computed axial tomography scan) because it does not use radiation. An MRI scanner consists of a large doughnut-shaped magnet that 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 examination, 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 cervical spine when the scan focuses on that area.
Why It's Done
MRI can detect a variety of conditions of the cervical spine as well as problems in the soft tissues within the spinal column, such as the spinal cord, nerves, and disks.
This test is used to evaluate injuries of the seven cervical spine bones or spinal cord. Doctors also use it to:
assess the anatomy of the cervical spine
help plan spinal surgery
monitor changes in the spine after an operation
MRI of the cervical spine can be useful in evaluating problems such as pain, numbness, tingling or weakness in the arms, shoulder or neck area, and can help detect certain chronic diseases of the nervous system. It also can help diagnose tumors, bleeding, swelling, infections, or inflammatory conditions in the vertebrae or surrounding tissues.
A cervical spine MRI usually doesn't require any 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 (but braces and dental fillings won't interfere with the scan).
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 obtain the highest quality MRI results, your child will need to stay still during the scan. For this reason, sedation may be required, especially for infants and young kids, who are likely to have difficulty staying still for the test. If sedation is needed, food and liquids will be stopped at a certain point before the MRI to allow your child's stomach to empty. It's important to notify the MRI technician of any illness, allergy, previous drug reactions, or pregnancy.
Sedation medications are usually given through an intravenous (IV) line (small tube in a vein) to help a child stay asleep during the entire test. Sedation is also helpful for kids who are claustrophobic. To relieve anxiety before and during the test, some patients take an oral sedative on the way to the hospital or radiology center.
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. It highlights certain problems of the cervical spine (such as infection or inflammation) 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.
You can stay in the MRI room with your child until the test begins, and in some centers you may be able to stay throughout the test. Otherwise, you'll join the technician in an outer room or be asked to stay in a waiting room.
If you're nearby you'll be able to watch through a large window and talk to your child through an intercom during breaks between the scans. This can soothe your child if he or she is awake in the MRI machine.
An MRI of the cervical spine usually takes about 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 above your child's neck. The table will slide into the tunnel and the technician will take images of the neck. Each scan will last a few minutes.
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.
MRIs are 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 is 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 looked at by a radiologist who's specially trained in interpreting the scans. The radiologist will send a report to your doctor, who will 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.
MRIs are safe and not difficult to complete. No health risks have been 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, discuss the risks and benefits of sedation with your doctor. 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 you explain that the neck will be examined and that the equipment will probably make knocking and buzzing noises.
It may also help to remind your child that you'll be nearby during the entire test.
If an injection of contrast fluid or sedation is required, 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. Your doctor may suggest that you and your child take a tour of the MRI room before the test.
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.