- What is an MRI?
- How does an MRI work?
- How is an MRI different than other imaging?
- What are MRIs typically used for?
- Is MRI a safe option for me?
- How do I prepare for the test?
- What can I expect?
- When will I know my results?
What is an MRI?
An MR or MRI stands for Magnetic Resonance Imaging, which uses a magnetic field and radio waves to generate cross sectional pictures of your body to show the existence of injury, disease, or atypical conditions of the body. It is a painless and extremely safe procedure because no radiation is used. Aided by a computer, MRI is able to produce an image of bone and soft tissue from many different body angles or planes. This enables our physicians to quickly and precisely diagnose a wide variety of conditions.
How does an MRI work?
Using magnetic fields instead of radiation, images are obtained by surrounding the area of the body the doctor wishes to study with a magnet, which causes water molecules inside your body to move. In some cases, contrast may be used to provide a more detailed study. The computer will pick up on the movement and convert it into images for your radiologist to examine and interpret.
How is an MRI different than other imaging?
CT scans use x-rays to make pictures and therefore small amounts of ionizing radiation, MRIs are completed using no radiation and therefore a good alternative for patients who cannot tolerate or do not wish to be exposed to radiation. Because radiation is not used, there is no risk of exposure to ionizing radiation during an MRI procedure.
What are MRIs typically used for?
MRIs may be used to examine many different parts of the body including, the brain, spine, joints, abdomen, pelvis, breast and vascular system. MRIs are sometimes used in the diagnosis of carotid artery disease, screening for intracranial aneurysms, and screening for renal artery stenosis.
Is MRI a safe option for me?
Due to the strong magnetic force, patients with implanted pacemakers must have FDA approval for their specific device prior to obtaining an MRI. If the device is not cleared, you may not be a candidate for MRI. Additional devices which should not be used in combination with an MRI include: some older intracranial aneurysm clips, cochlear implants, certain prosthetic devices, implanted drug infusion pumps, neurostimulators, bone-growth stimulators, certain intrauterine contraceptive devices, or any other type of iron-based metal implants. Some of the contrast dye used in some MRI may cause an allergic reaction, please notify your physician if you are sensitive to medications. You should also notify him/her if you have a history of kidney disease, kidney failure, kidney transplant, liver disease, or you are on dialysis.
Saint Francis takes MRI safety seriously and takes measures to ensure that our patients are always in the safest care.
How do I prepare for the test?
You should limit the amount of metal on your clothing, hair, and be prepared to remove all hearing aids, jewelry, and removable dental work. Tell your doctor if you are afraid of close spaces (have claustrophobia). Your physician may prescribe medication to help you feel sleepy and less anxious, or your doctor may suggest an “open” MRI, in which the sides of the machine are open and not as close to your body.
What can I expect?
Exam times vary depending upon the area being scanned, however, most exams will be between 30-60 minutes. In order to obtain quality images you will be required to remain completely still during your exam. You will be met by our MR technologist who will be performing the examination. The technologist has completed a rigorous course of education and training, and they work under close supervision of the radiologist to assure the most accurate results from your examination. The technologist will position and secure you on the imaging table. The slightest movement during the exam can blur the image and result in the need for repeated images. During the scan you will hear loud noises. The technologist will provide ear plugs or headphones to protect your hearing. The technologist will not be in the room during the procedure, but will communicate through an intercom and will observe you at all times through a window. Occasionally, you may feel a warming sensation. If it becomes uncomfortable, please inform the technologist.
When will I know my results?
The radiologist will study your films and report the findings to the referring physician within 24 hours. Your referring physician will discuss the MRI results with you.