New MRI Opens New Doors

Magnetic Resonance Imaging (MRI) is an important imaging technique used in the medical field to diagnose many diseases and detect abnormalities in the human body non-invasively. In the neurological sense, an MRI is often performed to obtain an inner image of the brain if unusual activity is suspected. For example in the case of multiple sclerosis (MS), abnormal spots called lesions can be detected with an MRI before clinical symptoms occur. MRIs have advantages over other imaging methods because this system is thorough and can be used to detect small subtle changes during the early stages of diseases. One limitation is that the scans usually take several hours to complete.

Now, thanks to dedicated researchers at the University of Illinois in Chicago, the world’s most powerful MRI is ready to be used to help the first patient. The team’s machine received final approval from the Food and Drug Administration (FDA) in the cusp of the 2008 new year. With an entire journal article solely dedicated to the safety of the machine in the Journal of Magnetic Resonance Imaging, the 9.4 Tesla machine will open up a new field in medical imaging, particularly neurology.

Typical clinical MRI scanners have magnetic field strengths of 0.2 to 3 Tesla. At these strengths only the movement of water molecules can be visualized, which limits the observation of metabolic processes in the brain to abnormal cystic or tumor formations and abnormalities in blood vessels or the heart. In 2003 MRIs with magnetic field strengths as high as 8 Tesla were accepted by the FDA, but to date, the 9.4 Tesla scanner is the most powerful clinical scanner that is large enough to acquire images from the human brain.

The 9.4 Tesla MRI allows doctors to visualize molecules other than water. For example, doctors will now be able to perform sodium imaging to determine whether a brain tumor is shrinking, growing, or migrating all in one visit. Previous MRI scanning required that the patient make several trips to the hospital over a period of weeks and sometimes even months. The reason that only one visit is necessary with the 9.4 Tesla scanner is that this high magnetic field strength allows more molecules to be visualized in a shorter period of time in comparison to the lower strength scanners that are currently being used. Imaging technology is now moving towards patient studies such as sodium imaging and towards safety testing for oxygen and phosphorus imaging in humans. Researchers are hoping that this scope can even be extended to other, more rare molecules in the future.

Analyzing a patient’s metabolic pattern after the administration of a therapeutic agent will allow doctors to customize treatment plans as well as determine the optimal type and amount of drugs to prescribe their patients. There are no known harmful side effects of undergoing an MRI besides the exposure to magnetic fields which should be avoided during pregnancy. Patients undergoing an MRI procedure sometimes experience mild nausea or claustrophobia from being inside of a chamber.

Currently MRI is the preferred imaging technique in diagnosing and monitoring diseases such as stroke, tumors, blood vessel abnormalities, infections, Multiple Sclerosis, and many other neurological and non-neurological diseases.

Reference

University of Illinois at Chicago (2008) World’s Most Powerful MRI Ready To Scan Human Brain. ScienceDaily.