Using non-invasive transcranial magnetic stimulation, or TMS, researchers at Ohio State Wexner Medical Center may have found a way to help prep a stroke victim's brain prior to physical therapy to aid a more complete recovery.
When one side of the brain is damaged by a stroke, the corresponding healthy part goes into overdrive in order to compensate, said Dr. Marcie Bockbrader, principle investigator of the study. She believes the hyperactivity in the healthy side may actually slow recovery in the injured side.
The technology, called NexStim, employs TMS to prepare a stroke patient's brain for physical therapy by sending low-frequency magnetic pulses painlessly through a victim's scalp to suppress activity in the healthy part of the motor cortex. This allows the injured side to make use of more energy during physical therapy, which immediately follows the transcranial magnetic stimulation.
"This device targets the overactive side, quieting it down enough, so that through therapies the injured side can learn to express itself again," said Bockbrader, an assistant professor of physical medicine and rehabilitation, in a new release.
The restoration of the balance of activity between the healthy and injured parts of the cortex, she believes, will not only help heal the brain, but allow for a more complete recovery of movement in the stroke victim.
An important part of the procedure is the targeting of the precise part of the motor cortex that is injured in order to stimulate the corresponding healthy part into "keeping quiet." These locations are determined using a technology similar to GPS, according to co-investigator Stephen Page, an associate professor of Health and Rehabilitation at Ohio State. This precision targeting also means the TMS can be accurately applied during repeat sessions.
In order to test the hypothesis, NexStim will enroll approximately 200 recent stroke victims in a double-blind, randomized clinical trial. To qualify, participants must have had a stroke between 3-12 months ago and have weakness in the arm and hand on only one side.
The trial will last eight months and involve up to 29 visits by each participant. In addition to Ohio State Wexner Medical Center, the other participating institutions are: Mayo Clinic in Arizona; Ranchos Los Amigos National Rehabilitation Institute in California; Shepherd Center in Georgia; Rehabilitation Institute of Chicago; Indiana University; Spaulding Rehabilitation Hospital in Massachusetts; Columbia University; Burke Rehabilitation Center in New York; Duke University; University of Cincinnati; and TIRR Memorial Hermann Hospital in Texas.