Types of MRI Machines

A magnetic resonance imaging (MRI) machine is commonly used to help physicians diagnose their patients symptoms. It allows your physician to see images of internal structures in your body. Unlike an X-ray, and MRI is very detailed and can provide your physician with valuable information to help tailor your treatment regimen appropriately. There are different types of MRI machines in use today.

Identification

An MRI machine is basically a giant tube with a table that the patient lies on. The patient is placed into the tube either feet or head first depending ont he area that is being examined. Inside the large tube there are magnets, which are not visible to the patient. When the machine is turned on the magnets rotate around the patient and create a situation where the patient is in a low strength magnetic field. The MRI machine is attached to a sophisticated computer system. The computer translates the information from the MRI to produce detailed images of your organs and tissues. The result is a document similar to an X-ray that can be interpreted by your physician.

Significance

MRI's are often used to diagnose conditions such as tumors, developmental issues, damage caused by a stroke and chronic conditions such as Multiple Sclerosis. Physicians can also gain information about changes and injuries to the spinal column and vertebrae, the joints, and the structure of the heart muscle. MRI's can also detect problems in many of the internal organs and can be used in cases of suspected breast cancer. The benefit of an MRI compared to an X-ray is that it is much more detailed, it can view more then just bones and joints, and it can produce 3-D images allowing the body to be viewed from many angles.

Types

There are two main types of MRI machines. Open and closed. They are both have a top over the patient. The main difference is in their size and how much the machine surround the patient. A closed machine is a smaller and more narrow tube and provides the best images. See the image at the top of the article.
An open MRI machine is open on three sides, making it more comfortable for the patient. However the images are not as good since the magnet is not traveling around the whole body.

Considerations

A closed machine is the preferred type of MRI by physicians due to more accurate pictures. However due to the fact that the top of the machine is just inches above a patient's face it can be uncomfortable for many patients and create feelings of claustrophobia. In addition a closed MRI machine can only take patients up to three hundred pounds.
With an open MRI, the magnets do not circle around your body so its imaging capabilities are more limited. There are some tests an open MRI machine can not do. One plus is that an open machine can take patients up to four hundred and fifty pounds.

Features

With advances in technology there are now also MRI's that allow the patient to sit or stand in the machine. See the picture here. This is extremely helpful when the physician needs to see the effects of weight bearing on the body. In the case of back pain, the pain or pressure may subside as the patient lies down in an open or closed MRI. However upon sitting or standing the cause of the problem may be better detected. A downside is that the physician must place the patient in a painful position while performing the scan. On the plus side some models even come with a TV the patient can watch during testing.

Resources

• Mayo Clininc/MRI
• Radiology Info