MRI is also known as Magnetic Resonance Imaging. The MRI scanner creates images that represent slices through the body, without using X-rays. MRI uses a powerful, but safe magnetic field and radio waves like those that transmit FM radio stations.
The combination of the magnetic field and radio waves is used to create images of body structures, including the brain, spine, joints, abdominal and pelvic organs and blood vessels. MRI scans are used to diagnose tumors, strokes, back problems, joint problems, diseases of arteries and many other disorders and abnormalities. The images produced may demonstrate conditions that do not show up on X-ray tests. The results may help determine your diagnosis and/or the best course of treatment for you.
Your physician's nurse or ALMH personnel will give you complete instructions prior to the exam. The preparation will vary, depending on the area being imaged. If the exam includes the abdomen or pelvis, you will not be able to eat or drink for several hours before the exam. In some cases, doctors will give patients with claustrophobia a sedative prior to the exam to help the patient relax.
You will be asked to change clothing and remove jewelry before the exam, and we will provide a locker for you to place your personal items in. You should not wear make-up, since some brands contain metallic components that can interfere with the exam, especially if the MRI is of the head or neck. Please check in at Central Registration in the Main Lobby before reporting to the Radiology Department if you have not been preregistered over the phone.
During the Exam
The MRI scan will be performed by a registered radiology technologist, who is specially educated, trained and certified.
While most people can undergo an MRI exam without problems, some cannot. The staff in the Radiology Department will ask you questions like the following:
- Do you weigh more than 300 pounds?
- Can you lie flat for the duration of the exam?
- Do you suffer from claustrophobia?
- Are you pregnant?
Also, since the MRI is a powerful magnet, you will be asked the following kinds of questions:
- Do you have any implanted devices like a cardiac pacemaker, aneurysm clip, neurostimulator, infusion pump or hearing aid?
- Do you have metal shrapnel in your body or metal fragments in your eyes?
Remember the questioning process is a two-way street. After providing all the necessary information, please let us know of any concerns you have about the upcoming exam. The technologists expect questions; part of their job is to answer questions and make certain you are comfortable with the exam.
Allow a total of two hours for the entire procedure. When you arrive at the MRI center, you will be asked to remove all personal possessions such as your watch, wallet and car keys along with any other metallic items. It is very important not to take anything that could be affected by the magnet into the examining room. For example, the information on your credit cards could be erased if you had them in your pocket during the exam!
During the examination, you will lie on a padded table and be positioned in the magnet so the appropriate part of your body is ready to be scanned. The magnet, or MRI unit, looks like a large box with an open-ended tunnel running through it. The table will move part way into this "tunnel". Sometimes a "coil", which is really just a radio receiver, will be placed around the part of the body being scanned. The MRI unit makes loud clanking and banging sounds. You will be given ear plugs or be allowed to listen to a radio station or CD of your choice. The technologist will talk with you during the exam. The technologist will let you know when to hold your breath, how long to hold still and how things are going.
For some exams, the technologist or a nurse will start an IV to give you a contrast agent that highlights certain organs, blood vessels, tumors, etc. Some patients may need to be given a sedative through the IV if they are very claustrophobic.
Once the study is complete, the images will be studied and interpreted by a radiologist, who will compare the MRI scan to previous MRI scans, CT scans and X-rays and will send a report on the MRI scan and its findings to your physician.