This imaging method shows activity in different areas of the brain.
Functional magnetic resonance imaging, or FMRI, is a special type of magnetic resonance imaging (MRI) that measures brain activity by detecting changes in blood flow.
When the brain area is more active, it consumes more oxygen, so blood flow to that area increases.
An FMRI can reveal which areas of the brain perform specific functions, such as thought, speech, or movement.
The imaging method is used to help doctors see the effects of diseases such as stroke, trauma, brain tumors, or Alzheimer’s.
It can also help guide doctors when performing radiation, surgery or other treatments for the brain.
The science was developed in the 1990s by scientists Segi Ogawa and Ken Cuong.
The fMRI Procedure
Like all MRI procedures, an FMRI uses a large device (about the size of a truck), a powerful magnet, and radio waves to view organs and structures in the body.
An FMRI usually takes an hour or less to perform.
Prior to the procedure, you will need an injection of contrast sources to help provide more detail in the images.
You will get it through the vein (IV) line in your hand or arm.
If you have anxiety or claustrophobia, you may be anesthetized before your FMRI.
You will be placed on the dynamic exam table. Your head can be placed in a device designed to keep you permanent. You may also be given special goggles or earphones to wear.
A technician or radiologist will transfer you to the magnet of the MRI unit. Doctors will perform imaging tests while working on a computer outside the examination room.
A technician will be able to see, hear and talk to you on the intercom.
It is important that you stay in touch during this procedure. You may even be asked to hold your breath at times.
An FMRI should be painless, but you may have trouble lying.
When the procedure is complete, your IV will be removed.
Before an fMRI
Before doing an FMRI, tell your doctor if you have a serious health condition, especially severe kidney disease.
Also, tell your doctor if you have had any recent surgery or if you are likely to become pregnant.
Be sure to remove all jewelry and any metal or electronic equipment before performing the FMRI.
Tell your doctor and radiologist ahead of time if you have any metal objects or medical devices in your body.
After an fMRI
You can resume your normal activities immediately after the FMRI unless your doctor tells you to.
In rare cases, some people experience side effects such as nausea, pain, or an allergic reaction to the injection medium. Tell your doctor if you notice any unusual symptoms.