Magnetic resonance imaging (MRI) of the brain is a diagnostic exam that uses a strong magnetic field, radio waves, and a computer to generate images of the inner structures of the brain. This test can be used to evaluate symptoms such as severe headache, memory loss, blurred vision, seizures, slurred speech, and loss of balance.
Brain MRI scan is useful in detecting tumors, strokes, brain injury, enlarged spinal fluid cavities (hydrocephalus), and changes in the brain associated with dementia.
Your doctor may recommend a brain MRI if you have symptoms that could be caused by a brain disease or disorder, such as:
- Tumors, including metastases
- Developmental anomalies
- Hydrocephalus (enlargement of spinal fluid cavities in the brain)
- Epilepsy (seizure disorder)
- Bleeding (hemorrhage)
- Multiple sclerosis
- Eye and inner ear disorders
- Pituitary gland abnormalities
- Aneurysms, blood vessel blockages, or clots
Brain MRI may also be recommended when planning for brain surgery, radiation therapy, or biopsy.
- Brain MRI scan is noninvasive and painless.
- In a single scan, brain MRI can evaluate soft tissue and blood vessels.
- MRI scanning does not expose you to any ionizing radiation.
- Brain MRI images offer a high level of detail which makes them useful for detecting very small abnormalities, like tumors at an early stage.
- Brain MRI can detect stroke at an early stage since the exam is very good at detecting changes in fluid motion (called diffusion). These changes may appear within less than 30 minutes of a stroke.
- Certain medical devices implanted into your body may be at risk of malfunction due to the strong magnetic environment. See Can I have an MRI if I have metal in my body?
- In very rare cases in patients with poor kidney function, nephrogenic systemic fibrosis is a possible complication when contrast is used. ARA follows all American College of Radiology (ACR) guidelines for screening kidney function with all applicable contrast agents.
- Pregnant women should consult with their physician prior to an MRI exam. However, there have been no documented negative effects of MRI in the many years of its medical usage, and MRI is often the method of imaging chosen for pregnant women and fetuses. It should be noted that MRI contrast agents are not recommended to be used during pregnancy unless the benefits far outweigh the risks.
- The ACR states that current information suggests breastfeeding is safe after the use of intravenous contrast. Please discuss your breastfeeding options with your medical provider.
- Brain MRI is available at multiple ARA imaging center and usually takes between 20 to 45 minutes to complete.
- You will be asked to change into a gown. You must remove all jewelry and metal from your body.
- You’ll be placed on a moveable exam table which may have straps or bolsters to help keep your body from moving.
- A special coil that enhances the MRI signal will be placed near the parts of the body to be examined.
- If your study requires contrast, your technologist will place an intravenous (IV) line into your arm or hand to administer the contrast. IV placement may be uncomfortable and may cause bruising later but for most this is not the case. A saline solution drip may be used to help keep the IV line open.
- The technologist will leave the MRI room where you are and conduct the exam from a computer in a control room. You will be able to speak with the technologist at all times. The technologist has direct visualization of you and the room. They will keep you informed of what is happening as your exam progresses.
- When the procedure begins, the table moves you into the magnet, which is a cylinder-shaped machine.
- MRI scanners are constructed with short tunnels that are open on both ends. Most people do not find this to be uncomfortable, but if you are anxious, please mention this to your scheduler. ARA may be able to schedule your exam on one of our open-bore or short-bore MRI scanners or plan for you to have light sedation. ARA technologists and our clinical staff are experts at helping people through MRI exams with minimum anxiety.
- During the exam you might feel warmth in the body part being examined. If this becomes uncomfortable, let your technologist know.
- When the images are being taken, you will hear loud knocking, tapping or thumping sounds. Earplugs or headphones with music are provided before the test begins.
- In rare cases, some patients experience side effects from the contrast material, such as nausea or headache. If you experience any discomfort, let the technologist know.
- You will be required to change into a gown. If possible, leave all jewelry and metal objects at home.
- Unless you are told otherwise, you may follow your normal diet and routine before the exam. You should take all your medications as usual.
- Some MRI exams require a prep which may include no food or drink for a specified time before the exam. Your scheduler will inform you of preparations if needed. If you are not given special instructions, you may follow your normal diet and routine before the exam.
- Ask your doctor for specific directions about your daily medications if you have been asked to refrain from taking them.
- Be sure to tell your technologist about any illness or allergies you may have. Also, provide a list of your current medications.
- Be sure to tell your scheduler and technologist if you are or might be pregnant.
- If you suffer from claustrophobia, panic attacks or anxiety, you might choose to receive sedation before the exam. Please mention this to your scheduler when making your appointment.
- Before you schedule an MRI, refer to the section Can I have an MRI if I have metal in my body? to get more information about metal devices, implants, or any other metal that might be affected by the magnet.
- In some cases, an X-ray may be taken before the MRI to detect any metal that could be located inside your body.
A radiologist, a physician specifically trained to interpret radiological examinations, will analyze the images and send a signed report to the provider who referred you to ARA. The physician will then share the results with you.