Brain imaging technique could improve treatment for infants

Scientists are investigating a more accurate brain imaging technique that could improve outcomes for children and will work with cryogen-free sensors.

The five-year project is being undertaken by scientists from Nottingham University and University College London (UCL).

Magnetoencephalography (MEG) maps brain activity by measuring the magnetic fields generated by electrical currents that occur naturally in the brain. A £1.6m Collaborative Award in Science from Wellcome is funding the construction of a new type of MEG scanner which could quadruple the sensitivity of current devices.

Dr Matthew Brookes and Prof Richard Bowtell, in the School of Physics and Astronomy are leading the research in Nottingham, where they have designed and built a 3D printed prototype wearable helmet and are in the early stages of developing the new MEG system.

Dr Brookes said: “Quantum technology has allowed the development of a new type of optical sensor which has the sensitivity to detect the weak magnetic fields from the brain. Unlike current technology, these new sensors can operate at room temperature, so they can be placed directly on the scalp surface. Our calculations show that by getting the sensors closer to the head we can quadruple the sensitivity of the field detection. This will revolutionise the kind of effect that we are able to detect from the human brain.”

According to Nottingham University, most current MEG systems are cumbersome and built around a small bore into which a participant’s head is gently clamped because the sensors, which have to be kept at minus 269 degrees, cannot be moved. This static, one-size-fits-all system restricts the subject groups that can be scanned and the experimental questions that can be addressed.

Work on the project began two years ago to assess the potential of quantum sensors in computational simulations. A small number of quantum sensors were then purchased and used to show, experimentally, that the expected improvement in sensitivity could become a reality. Based on this pilot data, they have now received the Wellcome award to construct a fully functional multi-channel MEG system based on quantum sensors, of which £800,000 is funding Nottingham’s contribution.

While the physics-based development needed to make the scanner work is being carried out in Nottingham, experts at UCL are carrying out detailed computational and theoretical modelling of the brain to frame the neuroscience and establish what neuroscience questions can be addressed.

The research project, ‘Moving functional brain imaging into the real world: A wearable, cryogen-free, MEG system’, is led by Prof Gareth Barnes, in the Wellcome Trust Centre for Neuroimaging at UCL.

He said: “The realisation of this system is a huge, but extremely exciting, challenge, with the potential to revolutionise the brain imaging field. Our simulations and pilot experiments have already shown the unique potential of the new quantum sensors. Our scanner will be worn on the head like a helmet, meaning subjects can undertake tasks whilst moving freely in an open and natural environment.”

The new scanner is expected to be particularly useful in children. Prof Richard Bowtell, director of the Sir Peter Mansfield Imaging Centre in Nottingham said MEG systems are essentially ‘one size fits all’ and sensitivity is limited for subjects with smaller heads, such as infants because their heads are further from the detectors.

“Room temperature quantum sensors can be mounted directly on the scalp of any subject,” he said. “This will give us a projected four-fold increase in sensitivity for adults, but the sensitivity could potentially be up to a 15 or 20 fold increase for children or babies.”