MRI (magnetic resonance imaging) is a diagnostic procedure that uses a combination of a large magnet, radio waves, and a computer to produce detailed pictures of inside your body.
How does an MRI scan work?
MRI does not use radiation, as do X-rays or computed tomography (CT scans). MRI creates a strong magnetic field around a patient by running an electrical current through a coil of wire. The magnetic field, along with a radiofrequency, alters the hydrogen atoms' natural alignment in the body. A short burst of radiofrequency waves alter the activity of the hydrogen atoms and they are detected and translated into a two or three-dimensional (2D or 3D) image of a body structure or organ by a computer. Cross-sectional views can be obtained to reveal further details. Patients who have experienced an MRI will tell you they tend to be very noisy. This is due to the quick expansion of the magnetically charged coil.
Most standard MRI units have a closed cylinder-shaped tunnel into which the patient is placed for the procedure. However there are a few “Open” MRI units that do not completely surround the patient. Some units may be open on all sides. While not magnetically as strong as standard machines, they can be useful for some procedures if a patient is Claustrophobic. We have an open MRI for patients at OHSU's Center for Health & Healing. Let your physician know if this is of some concern to you.
Schedule your MRI with us today: 503-418-0990. At OHSU Diagnostic Imaging Services your care and experience is our number one priority.
Innovation at OHSU has included the first deep brain stimulation surgery in North America, the first neuronal stem cell transplants in the world, and the first and most powerful intra-operative MRI facility in a children's hospital in the western United States. We also house a nationally leading neurosurgery training program and advanced fellowships in skull base and vascular, functional, and pediatric neurosurgery. Scientists in our department contribute to fundamental understanding of pain perception and of the brain's blood supply.
What should I expect during my visit?
Your appointment is unique to you. A scheduling professional will advise you on steps you will need to take before your exam. When you arrive for your appointment, a technologist will ask you to remove any clothing, jewelry, hairpins, eyeglasses, hearing aids, or other metal objects that may interfere with the procedure. You will be given a pair of earplugs for your comfort, as MRI's tend to be very noisy due to the quick expansion of the magnetically charged coil. If you are asked to remove any clothing, you will be given a gown to wear. If your procedure involves contrast dye, you might have an intravenous (IV) line started in the hand or arm.
During the exam, you will be asked to lie on a table that slides into a large, circular opening of the machine. It is very important that you remain very still during the procedure and at various times you may even be asked to hold your breath. The MRI technologist will be located in another room where the scanner controls are during your exam, however, patients are always in constant sight and communication with them. As the scanner begins to take images, bursts of radiofrequency waves energized protons in the patient. The energized protons of many Hydrogen atoms will be detected by the scanner and transmitted to the computer. After your exam you can discuss the findings with your ordering physician. Our radiologist will send an interpretation directly to them.