Magnetic resonance imaging (MRI) is a form of medical imaging that utilizes pulses of radio waves in conjunction with a magnet to generate images of organs and structures inside the body. The MRI machine may look similar to a CT machine, but no radiation exposure is involved in an MRI procedure. The patients are thoroughly screened prior to the exam and are asked to remove all jewelry to be metal free. During the test, patients lay on a table and the area of the body being studied is placed inside the machine. An injection of contrast material may be needed for further evaluation of the body structure. Depending on the exam, the allotted time could range from 45 minutes to over an hour. The MRI procedure might require specific Exam Preparations which can be reviewed prior to your appointment.
MRI may reveal issues that cannot be detected with other imaging methods or may provide additional information about a problem detected on an x-ray, ultrasound scan or CT scan.. The images collected from the MRI scan are digital, allowing them to be stored on a computer for further study. These digital pictures can also be reviewed remotely, such as in a clinic or an operating room. An MRI scan can be done for the:
- Head. MRI can look at the brain for tumors, an aneurysm, bleeding in the brain, nerve injury and other problems, such as damage caused by a stroke. MRI can also find problems of the eyes and optic nerves, and the ears and auditory nerves.
- Blood vessels. Using MRI to look at blood vessels and the flow of blood through them is called magnetic resonance angiography (MRA). It can find problems of the arteries and veins, such as an aneurysm, a blocked blood vessel or the torn lining of a blood vessel (dissection). Sometimes contrast material is used to see the blood vessels more clearly.
- Abdomen and pelvis. MRI can find problems in the organs and structures in the belly, such as the liver, gallbladder, pancreas, kidneys and bladder. It is used to find tumors, bleeding, infection and blockage. In women, it can look at the uterus and ovaries.
- Bones and joints. MRI can check for problems of the bones and joints, such as arthritis, problems with the temporomandibular joint, bone marrow problems, bone tumors, cartilage problems, torn ligaments or tendons or infection. MRI may also be used to tell if a bone is broken when X-ray results are not clear. MRI is done more commonly than other tests to check for some bone and joint problems.
- Spine. MRI can check the discs and nerves of the spine for conditions such as spinal stenosis, disc bulges and spinal tumors.