Unlike X-rays or CT, MRI images are created by using a magnetic field, radio waves, and a computer. The MRI is a noninvasive diagnostic test that takes detailed images of the soft tissues of the body. It allows your doctor to view your spine or brain in slices, as if it were sliced layer-by-layer and a picture taken of each slice. This test can help diagnose many things including disc herniation.
How does an MRI work?
A powerful magnet, computer and radio waves create detailed images so that the MRI scan can display its detailed images. The body is made up of millions of hydrogen atoms (the human body is 80% water), which are magnetic. In essence, an MRI measures the water content (or fluid characteristics) of different tissues, which is processed by the computer to create a black and white image. The image is highly detailed and can show even the smallest abnormality.
A dye (contrast agent) may be injected into your bloodstream to enhance certain tissues. The dye contains gadolinium, which has magnetic properties. It circulates through the blood stream and is absorbed in certain tissues, which then stand out on the scan.
What does an MRI show?
Nearly every part of the body may be studied with MRI. MRI gives very detailed pictures of soft tissues like the brain. Air and hard bone do not give an MRI signal so these areas appear black. Bone marrow, spinal fluid, blood and soft tissues vary in intensity from black to white, depending on the amount of fat and water present in each tissue and the machine settings used for the scan. The radiologist compares the size and distributions of these bright and dark areas to determine whether a tissue is healthy.
Bring your MRI Film in for Dr. Petersen to Review
After you get your MRI, you can bring it into your next appointment with Dr. Petersen and he will use it to help diagnose and treat you.