Deep brain stimulation (DBS) is a procedure that is used to treat movement disorders including Parkinson’s disease, tremor and dystonia. To improve symptoms, a DBS lead (insulated wire) is surgically inserted deep within the brain in sites known to control movement.
Electrical impulses are sent from the neurostimulator, also known as a brain pacemaker, to the lead implanted in the brain. The stimulation changes the pattern of electrical activity in the brain into a more normal pattern, thereby improving symptoms and returning more normal movement to patients.
Choosing the target location for the lead is of critical importance. Standard protocol among physicians around the world is to use a brain atlas developed from two French women who donated their brains to science many years ago. From there physicians superimpose the patient’s own brain MRI images and calculate a plan to implant the electrodes in the brain.
To improve the accuracy of current targeting approaches a team of researchers at the University of Minnesota Center for Magnetic Resonance Research (CMRR), are using high field magnets to visualize targets deep within the brain and are changing the way the location is chosen. The decision could significantly improve treatment outcomes by enhancing the accuracy of placing leads in the brain.
“Much like real estate, the positioning of the DBS lead is all about location, location, location,” said Noam Harel, Ph.D., associate professor of radiology at CMRR. “If the wrong location is selected the patient won’t receive the expected benefit or worse, it could have adverse side effects.”
In collaboration with Jerrold Vitek, M.D., Ph.D., professor and chair of the University of Minnesota Department of Neurology, Vitek is doing groundbreaking work in microelectrode recording (MER) mapping.
What sets their MER mapping apart from standard protocol is that Harel and Vitek are developing three-dimensional patient-specific anatomical models of the brain that allows physicians to identify and pinpoint an exact target location. Instead of the clinical MRI strength of 1.5-3 Tesla (T), CMRR researchers use a much stronger MRI – 7T – so images are more distinct.
“Each patient’s brain is different. This three-dimensional model created by the 7T images allows us to literally ‘see’ the individual shape, size and orientation of the brain target area. We simply could not see that with the standard brain atlas.”
Harel adds that the University is uniquely positioned to do this research because they are a world leader in imaging technology with the capabilities and collaborative team to tackle these challenging health problems.
“Our belief and our hope is that we can use this technology to help patients with severe movement disorders. Joint efforts like this between scientists and physicians are moving us closer to that goal,” said Harel.