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Unlike other organs or parts of the body, the brain is always operating at its absolute energy limit – meaning it needs to maintain high levels of blood flow to deliver oxygen and glucose. Without adequate levels of these nutrients, brain injury may result which can lead to other complications in the brain such as stroke or dementia.
Putting brains to the test
Dr. David Mikulis, Senior Scientist, Toronto Western Research Institute (TWRI), and Dr. Joe Fisher, Anesthesiologist, have created a test that allows them to examine the health of brain blood vessels and determine whether they are managing brain blood flow to their full potential.
By joining a breathing device they developed to work with functional magnetic resonance imaging (fMRI), Drs. Mikulis and Fisher have gained a great deal of insight into the underlying interaction between the blood vessels and the nerves in the brain.
Brain blood flow increases in healthy blood vessels in response to increases in brain activity – but also in response to small increases in inhaled carbon dioxide. Unhealthy vessels may provide normal blood flow but will respond little to such stimulation. This "brain test" allows Drs. Mikulis and Fisher to identify exactly which vessels are abnormal and how abnormal they are.
Detecting early signs of dementia
To date, their research has shown that patients with minimal symptoms, who seem to be functioning normally, actually have slow deterioration of the nerves in the brain in the areas where the vessels are abnormal.
In addition to analyzing the health of brain blood vessels, the research may also have important implications for detecting early signs of dementia – specifically, vascular dementia. Their research in this area will use the brain stress test to better understand the role damaged blood vessels play in the development and progression of this disease: They believe that the areas in the brain with unhealthy blood vessels will be seen at a very early stage of dementia allowing doctors to start the right kind of treatment sooner improving the future quality of life.
Read more on The Toronto Star website.