3D Printed Helmet Enables World's First Wearable Brain Scanner

A wearable brain scanner developed by University College London and the University of Nottingham relies on a custom 3D printed helmet to hold an array of quantum sensors close to the scalp, letting patients move naturally during a scan. The system, known as optically pumped magnetometer magnetoencephalography, or OPM-MEG, is what its developers describe as the world's first portable brain scanner.

A brain scanner you can wear

"What we're doing here is a world first," said Gareth Barnes, head of magnetoencephalography at UCL. "It's a brain scanner you can wear. And that's very different from a brain scan that's typically a tube you get jammed into. It has changed the way we think about the brain and how the brain works, and it's allowed us to scan the brain in its natural environment. It's a big breakthrough for neuroscience."

Barnes and Matt Brookes, head of physics at the University of Nottingham, have spent the past decade developing OPM-MEG as an alternative to conventional MEG, which requires patients to stay still inside a fixed scanner. Brookes described that equipment as "a very big one-size-fits-all thermos flask into which everybody's head has to fit," noting that its magnetic field detectors must run at minus 269 degrees Celsius, kept behind a vacuum inside a rigid shell that holds them a relatively long way from the head. Any head movement blurs the resulting magnetic field, and because children's heads sit proportionally farther from the fixed sensors, sensitivity drops further for younger patients who also struggle to stay still through a scan.

Quantum sensors meet 3D printing

The sensors behind OPM-MEG originated in research aimed at making atomic clocks smaller and cheaper in the early 2000s, when US scientists found the same components could measure the brain's small magnetic fields without cryogenic cooling. Because the resulting sensors are no larger than a thumbnail, they can sit inside a lightweight, custom 3D printed helmet whose lattice structure positions dozens of them close to the scalp.

The helmet can be scaled to fit babies, children, and adults individually. Each sensor wires into a backpack worn by the patient inside a magnetically shielded room, leaving them free to move, stand, or walk during the scan.

Impact for epilepsy and beyond

The technology was developed initially for children with epilepsy, a group for whom conventional scanning is especially limited. "Children not only have small heads, but they also find it difficult to stay still within a conventional scanner," Barnes said. As a result, children are often scanned only when they are about 18, which means they have surgery only as adults, by which time their education is finished. Treating epilepsy earlier, or operating earlier, would be a big advantage to these children, and that's what this technology might allow.

Researchers are examining OPM-MEG's potential for conditions including Parkinson's disease, schizophrenia, dementia, and autism, along with applications in sports, such as scanning athletes for head injuries on the field, and in military settings for traumatic brain injury. Brookes and Barnes are working to extend the technology to map spinal cord activity to support research into neurodegenerative diseases such as multiple sclerosis.

Development was funded by Wellcome, which awarded Barnes and Brookes a five-year collaborative grant in 2016. The scanner remains in research use while awaiting medical device approval, with its developers hoping for clinical approval in 2027.