Noninvasive Brain Stim Teams with Neurorehabilitation

by Jennifer French, senior editor

April 2016 issue

The market for noninvasive brain stimulation devices, such as transcranial magnetic and electrical stimulation systems, has been largely driven by applications in psychiatric and psychological disorders. But there are now several commercial firms and research institutions pursuing clinical trials of rTMS or tDCS systems for applications in neurorehabilitation.

According to the recently published report, The Market for Neurotechnology: 2016-2020, the current neurorehabilitation market is approximately $400 million with a forecast growth rate of 11 percent over the next five years. To date, most clinical efforts in neurorehabilitation have focused on techniques to restore activities of daily living, which are heavily task- and movement-oriented. However, fueled by advances in our understanding of cortical plasticity, there has been a renewed effort to use brain stimulation to enhance neurorehabilitation.

In the years that followed Northstar Neuroscience’s failed EVEREST trial of epidural stimulation for post-stroke motor recovery, several new clinical trials have been launched looking at less-invasive interventions that could capitalize on the same cortical plasticity concepts that seemed promising a decade ago.

Among the firms pursuing this application are Nexstim and Magstim, two vendors of rTMS systems. Magstim is sponsoring an 80-patient study led by the University of Alabama using the firm’s SuperRapid device for the treatment of aphasia. That company is conducting another 50-patient study using the Magstim Rapid 2 for the treatment of motor symptoms related to Parkinson’s disease. Nexstim is continuing its efforts in stroke recovery despite failing a futility analysis [NBR Mar16 p6.]

Other smaller patient trials are underway exploring tDCS for motor learning in children with cerebral palsy at Spaulding Rehabilitation Hospital, as well as TMS for treatment of motor cortex inhibition for dystonia at Emory University, combined tDCS and upper extremity neuroplasticity in SCI at the Cleveland Clinic, and TMS and cognitive treatment for TBI at the Boston Medical Center.

Two recently published studies point to using rTMS to decrease undesirable muscle activity. One was conducted by Likhachev and colleagues at Republican Research and Clinical Centre of Neurology and Neurosurgery in Belarus. The team demonstrated that providing rTMS treatments to the motor cortex region of the brain decreased hyperkinesis severity for those with rare forms of dystonia.

Gupta and colleagues at North Eastern Hill University in India reported in the Journal of Medical Engineering Technology the combination of 15 minutes of daily rTMS followed by one hour of standard therapy over a 20-day period significantly reduced tightness of all targeted muscles in children born with cerebral palsy. Both studies focused on activity suppression rather than functional recovery; however, the decrease in rigidity opens further opportunities for movement for activities of daily living.

Halo Neuroscience is pursuing applications of its tDCS system in stroke recovery. The company’s Halo Sport device has been used to improve performance in professional athletics applications.