The FDA in the US has signed off on human tests for a new brain-mapping device designed to make surgery safer for patients with a brain tumour or severe epilepsy.
Dr Ahmed Raslan is a neurosurgeon at Oregon Health & Science University who helped develop the flexible film.
It has tiny sensors that rest on the brain’s surface and detect the electrical activity of nerve cells below.
Designed to help surgeons remove diseased tissue while preserving essential functions like language and memory, the technology is similar in concept to sensor grids already used in brain surgery, but the resolution is 100 times higher.
In addition to aiding surgery, the film should offer researchers a much clearer view of the neural activity responsible for functions such as movement, speech, sensation, and even thought.
Engineer Shadi Dayeh from the University of California, San Diego, is developing the innovation. He said: ‘Imagine that you’re looking at the moon on a clear night, then imagine [looking through] a telescope.’
John Ngai directs the BRAIN Initiative at the National Institutes of Health, which has funded much of the project’s development. He said: ‘We have these complex circuits in our brains. This will give us a better understanding of how they work.’
The film is intended to improve functional brain mapping, often used when a person needs surgery to remove a brain tumour or tissue causing severe epileptic seizures.
During an operation, surgeons place a grid of sensors on the surface of an awake patient’s brain, taking care not to tear the delicate film. Then, they ask the patient to do tasks, like counting or moving a finger.
The accuracy of a brain map depends on the number of sensors used.
Dr Raslan explained: ‘The clinical grid we use now uses one point of recording every one centimetre. The new grid uses at least 100 points.’
Each sensor on the new grid is a fraction of the diameter of human hair, and the grid is bonded to a plastic film so thin and flexible that it can conform to every contour of the brain’s surface.
Dayeh and Raslan say the team is already working on a wireless version that could be implanted for up to 30 days. That would allow people with severe epilepsy to be monitored for seizures at home instead of in the hospital.
Ultimately, the researchers hope to use this diagnostic tool as a brain-computer interface for people unable to communicate or move.
Scientists have already created this brain-computer interface using sensors implanted deep in the brain. However, a grid on the brain’s surface would be safer and could potentially detect the activity of many more neurons.
Dayeh’s research is part of the federal BRAIN Initiative, launched 10 years ago.
Ngai says the new grid promises to improve care for people with brain disorders.
‘Ultimately, the goal was to develop better ways of treating human beings, and I think this gives us a pretty big stride toward that goal.’
Credit: Fritz Liedtke/Oregon Health & Science University]
