Magnetic resonance imaging (MRI) creates detailed images of organs and other body structures using a large magnet, a computer and radiofrequencies. Unlike computed tomography (CT or CAT) scans or X-rays, MRI does not use radiation.

MRI can be used to diagnose or rule out certain neurological conditions, including:

• Alzheimer's disease
• Amyotrophic lateral sclerosis (ALS) or Lou Gehrig's disease
• Aphasia
• Ataxia
• Central pain syndrome
• Circadian rhythm disorders
• Complex regional pain syndrome
• Concussions
• Cranial base tumors
• Dementia
• Dizziness
• Epilepsy
• Essential tremor
• Facial nerve disorders
• Failed back surgery syndrome
• Headaches
• Huntington's disease
• Migraines
• Moyamoya disease
• Neuromuscular disorders
• Sleep disorders
• Stroke
• Tic disorders
• Transient ischemic attack (TIA)
• Trigeminal neuralgia
• Vascular dementia

Northwestern Medicine specialists* are committed to safe and effective X-ray exposure using the As Low As Reasonably Achievable (ALARA) philosophy and featuring new technologies that give you:

• More enhanced images
• More detailed images
• Greater capacity
• A more comfortable experience

During an MRI, you will:

• Be asked to remove jewelry, clothing, eyeglasses, removable dental work, hearing aids, etc.
• Be given a hospital gown to wear if you are required to remove your clothing.
• Have an intravenous (IV) line inserted in your hand or arm if you are having an MRI with contrast dye.
• Lie on a table that slides into a long, tube-like machine.
• Be able to see your MRI technician through a window.
• Wear a headset or earplugs to reduce the machine's noise levels.
• Be asked to remain very still so the scan can create accurate images.

An MRI scan is painless, though you may feel discomfort from having to lie still for an extended period of time. Your technician will ensure that you are as comfortable as possible.