Magnetic Resonance Imaging (MRI) is a medical imaging modality that provides physicians with sectional images of a patient´s anatomy. This advanced technology uses magnetic field and radio waves to access the inner workings of the body. The pictures produced by MRI help the physician to clearly and accurately detect and define the differences between healthy and diseased tissues.
The magnetic field is produced by passing an electric current through wire coils in most MRI units. As you lie inside the MRI unit, radio waves are directed at the protons in the area of your body being studied. In the magnetic field, these protons change their position, producing signals that are detected by the coils. A computer then processes the signals and generates a series of images each of which shows a thin slice of the body. The computer compiles the images into a three-dimensional representation of the body, which can be studied from many different angles on a computer monitor.
Some patients find it uncomfortable to remain still during MR imaging. Others experience a sense of being closed-in (claustrophobia).
It is normal for the area of your body being imaged to feel slightly warm, but if it bothers you, notify the radiologist or technologist. It is important that you remain perfectly still while the images are being recorded, which is typically only a few seconds to a few minutes at a time. You will know when images are being recorded because you will hear tapping or thumping sounds when the coils that create the magnetic field are turned on. You will be able to relax between imaging sequences.
Our radiologist, a physician specifically trained to create and interpret radiology examinations, will analyze the images and send a signed report to your primary care or referring physician, who will share the results with you.
Breast MRI
Magnetic Resonance Breast Imaging (MRI, MR) is used to help diagnose breast cancer, characterize masses, and evaluate implants. Breast MRI is an excellent problem solving technology and often used to investigate breast concerns found by other means. MRI is also useful for determining the extent of disease in a known breast cancer patient and evaluating for any occult (hidden) masses.
Researchers have been investigating whether breast MRI may be useful in screening younger women at high risk of breast cancer as well as its role as a diagnostic tool. The American Cancer Society recently began recommending that women at very high risk of developing breast cancer have annual Breast MRI exams in addition to annual mammograms to increase the likelihood that breast cancer will be detected early. Because breast MRI is more sensitive than mammography, it can help detect cancer missed by mammography.
While Breast MRI has significant promise as a supplemental tool to mammography in the diagnosis of breast cancer, there are limitations with MRI. First, MRI cannot always distinguish between cancerous and non-cancerous abnormalities. Breast MRI is currently unable to effectively image calcifications, tiny calcium deposits that may indicate breast cancer. Mammography can reliably image calcifications, which are often associated with early-stage breast cancers. The use of mammography is complimented by the effective use of breast MRI.
How long will the exam take?
The average exam takes 45 minutes on the high field, one hour on the open field. It may take more or less than this depending on what part of the body is being studied.
I’m claustrophobic. How far do I go into the scanner?
In order to get the best pictures possible, the part of the body being studied, has to be in the middle of the scanner. Thus, if you are having a brain MRI, your head will have to be in the middle of the scanner. If you are having an ankle MRI, your ankle will be in the scanner, but your head will not. If you have severe claustrophobia, ask your doctor for some medication to help you relax during the scan. Please have someone accompany you who can drive you home if you do take any medication. Some exams can be performed on our open magnet for those patients who are severely claustrophobic.
Do I really have to hold still?
Yes. An MRI exam is composed of a series of images. Each series takes 3 to 5 minutes. Any movement during this time causes the pictures to be “blurry” and limits the radiologist’s ability to interpret the study. Also, we focus the exam on a specific part of the body.
I have metal in my body from prior surgery. Can I have an MRI?
Most people who have metal in their body after surgery can have an MRI. Certain devices can never go into the MRI machine. Some brain aneurysm clips (particularly older ones) cannot go into the scanner. If you have had any prior surgery, you must let the technologist know prior to the scan. Also, if there is any chance there may be metal in any part of your body from a prior injury or from grinding metal, please inform the technologist prior to the scan.
How and when will I get the results of the exam?
Your doctor should receive a written report in about three business days. If requested by your physician, a report can be called to him/her the day of the exam. Your results will be available to you from your doctor.