What is Magnetic Resonance Imaging?
Magnetic resonance imaging (MRI) is a radiological method of looking inside the body without the use of x rays. The MR scanner uses magnetism and radio waves to produce in detailed pictures of the human body. MRI is one the most advanced radiological techniques used to monitor and screen for disease. The technique provides medical information about the body more rapidly and more economically than physical examinations/laboratory tests performed by a physician. MRI is a unique radiological test because it does not involve the use of radiation.
How accurate is a brain scan?
The type of brain scan you will receive is known as a T2 scan. It can detect abnormalities of the brain the size of 5 mm and larger. A T2 scan will generate about 20 images of the brain.
What are some common uses of the MRI procedure?
MRI is used to detect brain tumors, strokes and play a role in the diagnosis of multiple sclerosis. In addition, it can be used to follow the progression of disorders head trauma, bleeding in the brain, tumors of the pituitary. The technique is also very useful to identify masses that may be impinging on the back of the eyes or ears.
What preparations are required for an MRI?
Because MRI scanning uses a strong magnetic field, one must wear loose clothes without any metal zippers or metallic buttons. No jewelry should be worn and all keys, coins, credit cards, dentures, eye glasses, etc must be removed. Since many cosmetics may contain metallic powders, it is advisable not to wear make up.
What happens during the scanning session?
At the radiology suite, you will be asked to lie down on a table and made comfortable. The table will then move you into a tunnel and the machine will obtain the necessary images. At this point in time, you have to hold your breath so as to avoid any motion artifacts. The entire scanning only takes a few minutes with no exposure of radiation
Some patients will require an injection of a contrast material to enhance the visibility of certain tissues or blood vessels. An intravenous line is placed in an arm and contrast material will be administered just when the bed moves into the tunnel.
What happens to the results of the scan?
If prior arrangements have been made with the radiologist, the results can be available the same day. It takes the radiologist 15-30 minutes to read the MRI and the results can be available soon after. A written report is prepared and the results will be sent to the primary care physicians. For a small processing fee ($20-30) the films can be mailed to you or your primary care physician.
Who should not have an MRI?
For the vast majority of people, there is no danger associated with having an MRI scan. For those people who have had the following should not undergo MRI:
- implanted insulin pumps
- aneurysm clips
- vascular coils and filters
- heart valves
- ear implants
- surgical staples and wires
One must inform the radiologist and technologist at the time of the exam if you are pregnant.
Why are MRIs so noisy?
Some MRI are very noisy some are not. The noise is due to the vibration in the machine and it is best to bring a set of ear plus. The new versions of MRI are less noisy. In addition, one may feel claustrophobic while in the tunnel. However, the new versions of “open” MRI do decrease such a feeling.
How long will the scan take?
Due to the fact that the MRI scan is a T2 weighted image only, the exam usually takes 5-10 minutes.
What if an abnormality is found on my MRI?
If the scan is abnormal, you will be referred to your physician for further work up and advice. Sometimes a more extensive MRI study with and without Gadolinium contrast will be required. Many of the abnormalities which can be detected will be of little consequence and are not tumors, aneurysms, etc. Most do not require surgery.
How often can I get an MRI?
If your health is okay and there is no abnormality, MRI can be repeated every 2-3 years. However, if a brain pathology has been detected one may need MRI every 3-6 months to follow progress
Is MRI scan reimbursement?
If one has been referred for an MRI scan because of symptoms, some insurance companies may cover and the same rule may apply to Medicare. However, routine screening MRI of the brain is at present not covered by anyone and self pay is required. A screening MRI usually costs about $200-400.
The body scan does not include a scan of the brain. Actually, the brain scan is not offered as a preventive measure. Since the occurrence of brain cancer and other detectable brain abnormalities are rare, this scan is never used as a preventive measure.
By ScanDirectory.com Staff
Updated: May 1, 2007