A new, non-invasive wearable magnetic brain stimulation device to improve recovery for stroke survivors has been deemed safe and effective. David Chiu, director of the Eddy Scurlock Stroke Center at Houston Methodist Hospital, Houston, USA, presented the preliminary late-breaking data at the International Stroke Conference (ISC; 19–21 February, Los Angeles, USA), and told delegates: “This technology would be the first proven treatment for recovery of motor function after chronic ischemic stroke.”
In an initial, randomised, double-blind, sham-controlled clinical trial of 30 chronic ischaemic stroke survivors, a new wearable, multifocal, transcranial, rotating, permanent magnet stimulator, or TRPMS, produced significant increases in physiological brain activity in areas near the injured brain, as measured by functional MRI.
“The robustness of the increase in physiological brain activity was surprising. With only 30 subjects, a statistically significant change was seen in brain activity,” said Chiu. “If confirmed in a larger multicentre trial, the results would have enormous implications.”
He further explained that magnetic stimulation of the brain was previously investigated to promote recovery of motor function after stroke. Thus, as the stimulation held the possibility to change neural activity and induce reorganisation of circuits in the brain, researchers introduced a new wearable stimulator.
Chiu reported that stroke survivors who had weakness on one side of their body at least three months’ post-stroke were enrolled in a preliminary study to evaluate safety and efficacy of the device. Half of the patients were treated with brain stimulation administered in twenty 40-minute sessions over four weeks. The rest underwent sham treatment, acting as controls. The team analysed physiologic brain activity before, immediately after and one month after treatment.
They found that treatment was well tolerated, and there were no device-related complications. Active treatment produced significantly greater increases in brain activity: nearly nine times higher than the sham treatment.
“Although the study does not prove that the transcranial stimulator improved motor function, numerical improvements were demonstrated in five of six clinical scales of motor function, as measured by a functional MRI test,” Chiu explained. The scales measured gait velocity, grip strength, pinch strength, and other motor functions of the arm. The team found that the treatment effects persisted over a three-month follow-up.
As Chiu strongly speculated that study results are a signal of possible improved clinical motor function after magnetic brain stimulation for patients after stroke, he highlighted the need for a large, multicentre trial to confirm them.