What is an MRI?
Most radiology imaging studies use x-rays to visualize what lies inside the body. For example, a chest x-ray allows the doctor to see through the skin and study the heart and lungs. Modern x-rays are very safe but do expose the body to some radiation.

Magnetic resonance imaging (MRI) is a different method of looking inside the body. Instead of x-rays, the MRI scanner uses magnetism and radio waves to produce remarkably clear pictures. The powerful magnetic field causes the hydrogen ions in the body to become magnetized and line up in a certain order. The data received is analyzed and turned into an image by a high-powered computer to create detailed image slices (cross sections) of your body. MRI can produce better soft-tissue images than standard x-rays and is better at distinguishing normal, healthy soft tissue from diseased tissue.

Why is MRI important?
This technology is important because MRI scans illustrate more clearly than ever before possible the difference between healthy and diseased tissue and can provide important information about the brain, spine, joints and internal organs. It can lead to early detection and treatment of disease and has no known side effects. Consequently, your physician will be better able to determine the most appropriate treatment for you.

Are there any contraindications to having an MRI?
Yes. There are contraindications to having an MRI. Due to the strong magnetic field, some patients with certain types of surgically implanted devices or objects cannot be scanned. Your physician will review your medical history and determine if an MRI scan can be performed on you.

How does an MRI scanner work?
Your body is composed of small particles called atoms. Hydrogen atoms, i.e. in water, make up 95% of the body. Normally, these hydrogen atoms within your body spin around at random. However, when you are placed inside a strong magnetic field, the hydrogen atoms line up and spin in the same direction as the magnetic field. When a radio wave is transmitted through the body, the hydrogen atoms give off a signal. That signal, with the aid of a computer, becomes the source of MRI information to produce two-dimensional images or three-dimensional volumes of a part of your body.

What causes the noise in the scanner?
The noise is caused by pulsations of electrical current through coils of wire called gradients. The stronger the main field, the louder the gradient noise.

How long do I have to wait for an appointment?
The demand for an MRI scans is high, and the waiting period for an MRI appointment ranges from 1 to 2 weeks for most exams. Urgent requests and emergencies are incorporated into the schedule as needed. When we receive a request for an MRI, we schedule an exam date as soon as possible according to need and appointment availability.

What should I do to prepare for my exam?
Most MRI procedures require no patient preparation before the examination. If your particular procedure requires preparation, our schedulers will inform your doctor who will, in turn, inform you of what preparation is needed.  If you are claustrophobic, please ask your doctor to prescribe medication for you and bring it with you to your appointment. If you have had previous imaging studies (x-rays, CT or MRI scans, etc.) that are relevant to your MRI, let our schedulers know where and when they were performed.  These films are required as comparison for reading your new MRI.  If you have any films in your possession, be sure to bring them with you to your appointment. 

What does an MRI look like?
An MRI is a two-dimensional image or three-dimensional volume of a part of your body. MRI images are viewed on a computer monitor and can be printed on film (like an x-ray) or recorded on optical discs and compact discs. One MRI exam consists of a series of MRI scans. Each scan ranges in length from a few seconds to a few minutes and can contain any number of two-dimensional images.

Will it hurt?
No. MRI is not painful. In fact, you will not feel anything. Before the exam is started, you will be given a call button, which will allow you to maintain two-way communication with the technologist throughout the exam. For some, claustrophobia can be a problem.  In such cases the patient can be partially or totally sedated.
 
How safe is the MRI contrast dye? I had a reaction to the dye I was given in CT, can I still be injected with MRI dye?
MRI contrast agents are very safe. Gadolinium chelates have been approved and used in MRI since the late 1980’s. The contrast is extremely well tolerated by most patients. Adverse events that do occur happen on a much lower frequency that with patient receiving iodinated contrast, used in CT or X-ray procedures.

What is an MRA?
MRA (magnetic resonance angiography) is a special type of magnetic resonance imaging (MRI) that looks at blood vessels and blood flow in virtually any part of the body with or without injection of contrast. A major advantage of MRA is that it can be performed as a non-invasive procedure, which has little risk of complications in comparison to conventional angiography or other related procedures. As a result, MR angiography is increasing in demand.

Can you scan my whole body while I'm in there?
No. With the MRI scanner, we can image almost any part of the body; however, each scan is limited to a specific body part or area. Each area we scan takes from 30-60 minutes.

Why do you need to know about metal implants in my head, if I'm having my back scanned?
Although we focus on one specific area when we scan you, your whole body does go into the scanner. We need to know about metal anywhere in or on your body because the magnet is never turned off, and just by entering the scan room, you are within the magnetic field. Certain metallic devices interfere with the scan, and their presence during the scan may cause injury to you. It is very important for us to know if you have a pacemaker or other implanted electrical device, a history of heart or brain surgery, cerebral aneurysm clips, shrapnel, or a history of getting metal fragments in your eyes. Please check our MRI safety (click) information section for more details.

How does MRI differ from a CT scan?
One of the most basic differences between the two tests is that Computerized Tomography (CT) Scanning uses x-rays and MRI does not. A CT scan uses faster scanning times and can be performed in patients with pacemakers and other metallic implants, but a CT scan does expose the patient to x-rays and risks allergic reactions to intravenously administered iodine-containing dye.  The MRI produces better images of the body's soft tissues and involves no x-rays or iodine dyes, but MRI scanning times are longer and are difficult for patients who are not able to hold their breath. Patients with pacemakers and intracerebral aneurysm clips cannot be scanned by MRI.

Getting the test results?
Very large amounts of data are created during these studies. A board-certified Radiologist, a doctor who specializes in analyzing these exams, will review the images, interpret the results, and send the results to your referring physician.  Your referring physician will contact you to discuss the MRI test results. Results are usually available within 72 hours.

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