Magnetic resonance imaging (MRI) is a noninvasive test doctors use use to diagnosis medical conditions. MRI use a powerful magnetic field , radiofrequency pulses, and a computer to produce detailed pictures of internal body structures. MRI does not use radiation (x-ray).
Physicians use an MRI exam to help diagnosis or monitor treatment for conditions such:
Tumours of the abdomen or pelvis
Diseases of the liver, such as cirrhosis, and abnormalities of the bile ducts and pancreas
Inflammation of the bowel caused by Crohn’s disease and ulcerative colitis or appendicitis in pregnant or younger patients
Malformation of the blood vessels and inflammation of the vessels (vasculitis)
What are the benefits vs. risks ?
MRI is a noninvasive imaging technique that does not involve exposure to radiation.
MR images of the soft-tissue structures of the body such as the liver and many other organs are sometimes more likely to accurately identify disease than other imaging methods. This details makes an invaluable tool in early diagnosis and evaluation.
MRI has proven valuable in diagnosing a broad range of conditions , including cancer, heart and vascular disease, and muscular and bone abnormalities.
MRI can detect abnormalities that bone might obscure with other imaging methods.
MRI allows physicians to assess the biliary system noninvasively and without contrast injection
The MRI gadolinium contrast material is less likely to cause an allergic reaction than the iodine- based contrast material x-rays and CT scanning
MRI provides a noninvasive alternative to x-ray, angiography and CT for diagnosing problems of the heart and blood vessels.
Risks:
The MRI exam poses almost no risk to the average patient when technologists follow appropriate safety guidelines.
If the exam uses sedation, there is a risk of using too much . however , the doctor will monitors your vital signs to minimize the risk
The strong magnetic field is not harmful to you however, it may cause implanted medical devices to malfunction or distort the images.
Nephrogenic systemic fibrosis is a recognized complication related to injection of gadolinium contrast. It is exceptionally rare with the use of newer gadolinium contrast agents. It usually occurs in patients with carefully assess your kidney function before considering a contrast injection.
There is a very slight risk of an allergic reaction if your exam uses contrast material .such reactions are usually mild and often resolve on their own. If you have an allergic reaction, a doctor will be available for immediate assistance . although there are no known health effects, evidence has shown that very small amounts of gadolium can remain in the body after multiple MRI exams.
LIMITATIONS OF MRI
High –quality images depend on your ability to remain still and follow breath-holding instructions while the technologist records the images. If you are anxious, confused or in severe pain, you may find it difficult to lie still during the MRI and the image quality will suffer. A large person may not fit into certain types of MRI machines. There are weight limits on the scanners. Implants and other metallic objects can make it difficult to obtain clear images. Patient movement can have the same effect. A large amount of ascites fluid in the abdomen /pelvis can also create artefact that results in low –quality MR images. If you cannot hold your breath, some MRI exams may be of limited quality as the picture will be blurry. An MRI exam typically costs more and may take more time than other imaging exams .Talk to your insurance provider if you have concerns about the cost of MRI.