Stroke rehab with high-tech: German neuroimplant used for the first time

With the help of a brain implant developed in Germany, the American University of Washington School of Medicine is testing a procedure designed to give stroke patients back more mobility. At the end of July, doctors used the brain-computer interface (BCI for short) developed by the Freiburg-based company Cortec on a human for the first time. The patient is a 52-year-old man who, according to the university, has severe movement restrictions in one arm and leg following several strokes.

The implant system, known as "Brain Interchange", is intended to support the motor functions of the upper limbs of stroke patients by promoting the formation of new connections in the brain. The implant is designed to send electrical impulses while a patient performs specific exercises. The researchers hope that this will increase the healing effect of the rehabilitation measures.

As the researchers explain, parts of the cerebral cortex are responsible for conscious muscle movement. If areas die off as a result of an oxygen deficiency caused by a stroke, this can lead to the loss of the ability to move certain parts of the body. However, if sufficiently large areas of the brain have survived the stroke and are still connected to other areas, they can strengthen the existing connections and form new ones.

Implant supports physiotherapy

Rehabilitation exercises stimulate the brain to repair the damaged network, also by healthy regions of the brain taking over tasks of the musculoskeletal system. This is where the implant comes in: While the patient performs certain movements, the device uses electrical impulses to stimulate the neurons to send electrical signals together. This joint firing of the neurons is intended to strengthen the connections between the surviving regions.

The timing of the method is crucial, explains neurosurgeon Jeffrey Ojemann from the University of Washington. "We want to activate the neurons when the brain is doing something you want to improve."

The implant consists of two thin silicone foils in which electrodes are embedded. Doctors place the foils on the surface of the brain over the area affected by the stroke. The implanted system is designed to continuously record brain activity, interpret the signals and deliver targeted electrical impulses in real time to promote the brain's ability to learn. According to Cortec, the implant communicates wirelessly with a laboratory computer during physiotherapy.

The university plans to treat four patients in this way in the first study. In a follow-up study, there will be eight. Cortec predicts that its brain-interchange technology can be adapted to various neurological diseases.

(dgi)