Diagnosis-Evaluation
MRI : Magnetic Resonance Imaging
(MRI) Test
MRI is an investigation used for obtaining clear pictures of soft tissues such as muscles, cartilages, ligaments, tendons and blood vessels, in addition to bone structures
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The MRI scanner is a large magnet that uses the natural magnetic properties of the body to collect data. A computer changes this data into images. It takes about 45-90 minutes to conduct an
MRI. There is no pain or discomfort during the procedure. As MRI is not an X-ray, radiations are not involved in the test.
The doctor should be informed if there is any metallic implant in the body, as the strong magnetic fields can disrupt the action of implanted metallic objects. People with cardiac pacemakers cannot be scanned and should not enter the MRI area. MRI is also not to be used for people with metallic objects in their bodies such as :
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Inner ear (cochlear ) implants
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Brain aneurysm clips
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Metallic
artificial heart valves
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Metallic stents (after angioplasty)
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Artificial joints
Watch, jewellery or any other metal object should be removed. The patient has to lie on the scanning couch and is then slid into the scanner. He should keep as still as possible during the procedure ; excessive movement can blur MRI images. During the test a humming noise occurs. Ear plugs are provided to the patient to reduce the noise. If there is any anxiety or discomfort, the patient can communicate with the technician through an intercom.
An MRI provides additional imaging information as compared to a CT scan, because of its superior tissue contrast resolution MRI performed with intravenous contrast may provide additional data about blood vessels.
As the effects of strong magnetic fields on a foetus are not well known, pregnant women are advised to avoid MRI scans.
