When Would I Need an MRI to Diagnose My Headaches?
MRI scans also can look at parts of the brain that aren't as easily viewed with CT scans, such as the spine at the level of the neck and the back portion of the brain. An MRI can’t diagnose migraines, cluster, or tension headaches, but it can help doctors rule out other medical conditions that may cause your symptoms, such as:
- A brain tumor
- An infection in your brain, called an abscess
- The buildup of fluid in the brain, called hydrocephalus
- Spinal cord problems, such as a herniated disc
Is It Safe?
Yes. The MRI exam poses no risk to the average person.
The scan is also safe for people who've had heart surgery and people who have these medical devices:
- Surgical clips or sutures
- Artificial joints
- Cardiac valve replacements (except the Starr-Edwards metallic ball/cage)
- Disconnected medication pumps
- Vena cava filters
- Brain shunt tubes for hydrocephalus
Some things may mean you shouldn’t have an MRI. Tell your doctor if you:
- Have a heart pacemaker
- A cerebral aneurysm clip (metal clip on a blood vessel in your brain)
- Are pregnant
- Have an implanted insulin pump (for treatment of diabetes), narcotics pump (for pain medication), or implanted nerve stimulators
- "TENS" device for back pain
- Metal in your eye or eye socket
- Cochlear (ear) implant for hearing problems
- Implanted spine stabilization rods
- Severe lung disease (such as tracheomalacia or bronchopulmonary dysplasia)
- Gastroesophageal reflux (GERD)
- Weigh more than 300 pounds
- Have trouble lying on your back for 30 to 60 minutes
- Claustrophobia (fear of closed or narrow spaces)
How Do I Prepare for an MRI Scan?
- Set aside about 2 hours for the test. In most cases, it takes 40 to 80 minutes, during which technicians will get several dozen images of your brain.
- Leave personal items such as a watch, wallet, including any credit cards with magnetic strips (they will be erased by the magnet), and jewelry at home if possible, or take them off before the scan.
What Happens Before an MRI Scan?
Sometimes, you’ll get a drug to make you feel relaxed and drowsy. You may also need to change into a hospital gown. Also, MRI machines can be loud, so if you’re sensitive to noise, ask for earplugs before the scan starts.
What Happens During the Test?
- As it begins, you'll hear the equipment making a muffled thumping sound that will last for several minutes. Other than the sound, you shouldn’t feel anything unusual during the scanning.
- For some MRI exams, you'll need a shot of a "contrast material" into your vein. It helps doctors see certain structures in your brain on the scan images.
- Feel free to ask questions. Tell the person giving you the test or the doctor if you have any concerns.
What Happens Afterward?
Generally, you can go back to your usual activities and normal diet right after a MRI test.