MRI, or Magnetic Resonance Imaging, machines are used around the world and of great importance in medicine for diagnosing all kinds of diseases and illnesses. From circulatory problems to cancer, MRIs provide physicians with eyes to peer inside the human body without using invasive procedures such as surgery. In addition, MRI units being manufactured today are open, and the patient can sit or stand instead of lying on a table.
MRI units are diagnostic machines that scan the internal structures of our bodies to detect abnormalities, or rule them out. "Magnetic resonance imaging is based on ... absorption and emission of energy in the radio frequency range of the electromagnetic spectrum," according to Joseph P. Hornak, Ph.D., author of The Basics of MRI.
These machines work on the principle of detecting protons in the hydrogen nuclei that make up 63 percent of our bodies in the form of fat and water molecules. Protons possess a characteristic called spin, and the powerful magnets in these machines align these hydrogen protons, while a computer assembles the data into detailed pictures. Different structures in the body produce different properties the MRI can pick up.
There are several major manufacturers of MRI machines in America and overseas. At present about 10,000 units are in use around the world, and take some 75 million scans per year, Hornak says.
Fonar, General Electric Healthcare, Bruker Biospin, Hitachi Medical Systems of America, Inc., Philips, Siemens, Varian and Toshiba Medical Systems are the major corporations that manufacture MRI machines. They produce different types of MRI units where the patients can lie down on a table, sit or stand for the scan, depending on what areas of the body are being imaged.
There are corporations that supply parts, service and accessories for MRI machines. Magmedix manufactures communication devices such as headsets and microphones allowing technicians and doctors to converse over background noise the machine makes.
MRI technicians must wear protective gear like vests because of powerful radio frequency waves the units produce, and Magmedix manufacturers these as well. Other companies provide service for these machines.
The Fonar corporation manufactures a unit called the Upright Multiposition MRI. It is the only MRI in the world where the patient can stand, sit or flex in a bending position while being scanned. This is especially advantageous when scanning the spine and joints, according to Fonar. The "open" environment of this unit is a good attribute because some people can't handle the claustrophobic feeling the traditional MRI machines can cause when you're in the donut hole.
One drawback to the MRI is the use of a contrast agent called gadolinium. The dye is not used in all image scans. When scanning arteries, the dye is injected into the arteries in order for the structures to show up. The use of gadolinium has been linked to a skin disorder called nephrogenic systemic fibrosis (NSF), or nephrogenic fibrosing dermotherapy (NFD), according to the Food and Drug Administration. The disease doesn't infect everybody injected with the dye but is disabling and can be deadly, warranting the warnings.