Wednesday, August 29, 2007

A New Tool for Diagnosing Alzheimer's Magnetoencephalography (MEG)


By Bob DeMarco
Alzheimer's Reading Room

This development has wonderful implications for diagnosing Alzheimer's; it has far reaching implications for those predisposed by genetics to Alzheimer's disease.



You will be hearing this word quite a bit in the coming months, Magnetoencephalography (MEG). If you read our previous post you will understand why this is likely. Researchers from the University of Minnesota Medical School and Brain Sciences Center at the Minneapolis VA Medical Center recently identified a way to diagnose Alzheimer's and other brain diseases. I am often asked what I am doing for myself now that my mother has been diagnosed with Alzheimer's. The answer to this question is quite long and detailed. I will answers this question when I can on my companion blog, I am an Alzheimer’s CareGiver. For now, I will be investigating the use and potential for Magnetoencephalography as a tool in diagnosing Alzheimer’s disease. As I learn more I will be posting that information on this blog.

For now I can tell you this, the procedure is very expensive and is out of reach financially for the majority of us who are genetically predisposed to Alzheimer’s. Perhaps in the future there will good medical reasons for insurance companies to catch the disease early and treat it. When this occurs the test will become more readily available for those with insurance and likely cheaper for those without that benefit. We can only hope and pay attention to developments

Source Brain Sciences Center, University of Minnesota

Applications

MEG provides scientists a vital neuroimaging tool to gain critical perspectives into the basic mechanisms of the cognitive processes of the healthy, functioning brain in the same lightning speed at which the brain itself operates.

MEG studies also allow researchers valuable insights into the dysfunctional brain with respect to neurological disorders and diseases such as: schizophrenia, stroke, mental retardation, dyslexia and Alzheimer’s disease through measuring these changes in the brain’s electro-magnetic fields.


Magnetoencephalography (MEG) is a rare, complex neuroimaging technique that allows scientists a unique view of the dynamic, interactive brain. There are only a few research centers in the world that have the expertise and capital to incorporate this advanced level of technology into their brain studies.

The uniquely powerful MEG machine at the Brain Science Center uses a non-invasive, whole-head, 248 channel, super-conducting-quantum-interference-device (SQUID) to measure small magnetic signals reflecting changes in the electrical signals in the human brain. The incorporation of liquid helium creates the incredibly-cold conditions (4.2 kelvin) necessary for the MEG’s SQUIDs to be able to measure fields that are literally billions of times weaker than the background magnetic field of the earth.

Investigators at the Center use the MEG to measure these magnetic changes in the active, functioning brain in the speed of milliseconds. Used in conjunction with magnetic resonance imaging (MRI), to relate the MEG sources to brain structures, and functional magnetic resonance imaging (fMRI), for optimal spatial resolution, researchers can now localize brain activity and measure it in the same temporal dimension as the functioning brain itself. This allows investigators to measure, in real-time, the integration and activity of neuronal populations while either working on a task, or at rest. The brains of healthy subjects and those suffering from dysfunction or disease are imaged and analyzed in these MEG studies.

History

This ever-evolving technology began as a single-channel system in the 1970s. Since then, MEG technology has been constantly updated and refined into its current state-of-the-art status. The MEG instrument at the Brain Sciences Center, is one of the few of its caliber in existence. Its 248 SQUID sensors make this imaging machine one of the most powerful and technologically advanced in the world.

What is the Brain Sciences Center?



Original content Bob DeMarco, the Alzheimer's Reading Room