Friday, January 28, 2022

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Magnetic Resonance Imaging (MRI)

MRI stands for Magnetic Resonance Imaging, and unlike most other imaging methods, it does not use any X-Rays or other high-energy radiation.  MRI machines use a very strong magnetic field to create and detect resonances in tissues inside the body.  This is a very safe procedure and causes no issues with normal tissue. 

MRI has become a preferred method for diagnosing potential problems in many different parts of the body. While X-rays are best for showing bones, MRI creates pictures that can show differences between healthy and unhealthy tissue. Doctors use MRI to examine soft tissue - like organs, muscle, cartilage, ligaments and tendons in many parts of the body.

When you have your study, you will be placed on a table and then moved through the body of the MRI, called the ‘coil’.  On some machines, the coil opening is quite small, and this can be a problem for larger patients (over 300lbs) or patients who are uncomfortable in confined spaces (claustrophobic).  Some of our scanners are ‘Open MRIs;’ they have a much less confined coil, and are more comfortable for patients who have issues with the traditional MRI.  Some folks who are very uncomfortable in confined spaces are given a sedative to help them relax.

In general, it is easier to get a good image with a higher magnetic field strength, and the field strength of the machines varies.  Open MRIs have lower field strengths than standard machines, but make up for it with enhanced processing power.  

MRI studies are used to visualize the head, brain, spine, and other joints, abdominal organs, and even the breast.  Breast MRIs are very effective in cancer screening, often detecting lesions that other technologies can miss.  Breast MRIs cannot be done in Open MRI machines.

The very strong magnetic fields in any MRI can cause certain problems, especially for the ‘high field’ machines.  You should be sure that you have no metal of any type in or on your body or clothes, since the magnetic fields can literally rip any metallic object away.  This means that you should not have any metal buttons or studs on your clothing, and you should empty your pockets.  You should not wear any watches or jewelry.  If you have a pacemaker, screws or plates, shrapnel, or any other metal items inside your body, tell us about them immediately and do not enter the MRI room until you are told it is safe to do so.

The examination itself is performed in a room that houses the MRI equipment. You'll be asked to lie down on a comfortably padded table that gently glides you into the magnet. While the scanner is operating, you'll hear some humming and occasional thumping sounds. These are normal and shouldn't worry you. In some cases, your doctor may have requested that you receive an injection of a contrast agent to give a clearer picture of the area being examined.

While you are in the machine, you should be very still.  Any movement of your body will decrease the quality of the image.  You will hear a series of loud noises; this is a normal and unavoidable part of the process.  The process typically takes thirty minutes to an hour.  In many cases a ‘contrast agent’ is injected into your body to improve the quality of the image.  This contrast agent contains no iodine and is usually well tolerated, but as always it is important to list any allergies you have on your admission forms.

Magnetic Resonance Imaging (MRI) is a dynamic way for doctors to diagnose certain diseases. MRI doesn't rely on x-rays. Instead, it uses a magnetic field and radio waves to create a very clear picture of internal body structures.

The most important thing for you to do is relax and lie still. Most exams take between 30-45 minutes, although some may take as long as 60 minutes.

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