Culture, history and society
2020 James Joule Medal and Prize
Professor Richard Bowtell for his outstanding application of physics to the innovative development of new hardware and techniques for biomedical imaging, and their application in medicine and neuroscience.
Professor Richard Bowtell’s work is distinguished by the deep physical insights and interpretations that he provides, but it is his breadth of expertise that has allowed him to make seminal contributions to biomedical imaging.
His contributions to the development of new technology, particularly in electromagnetic coil design, have had significant commercial impact.
Bowtell and colleagues have recently developed a completely new type of wearable magnetoencephalography system that allows brain mapping to be carried out during experiments in which the subject is free to move.
This opens up a range of new brain-mapping experiments and studies of previously inaccessible subject groups.
Magnetoencephalography, which maps weak magnetic fields generated outside the scalp by brain activity, is currently carried out using cumbersome scanners with liquid-helium-cooled sensors.
The wearable scanner uses miniature quantum sensors that can be mounted on the scalp. Crucial to the operation of this system is Bowtell’s development of a novel field-nulling system that uses biplanar coils to reduce the magnetic field around the head to less than a nano-tesla.
This field-nulling technology has been commercially licensed.
The biplanar coils were produced using methods that Bowtell previously developed for gradient coil design in magnetic resonance imaging (MRI). In earlier work, he contributed to the development of new methods for designing the actively screened, magnetic field gradient coils with distributed wire-paths, which are now used in all MRI scanners.
The resulting improvement in gradient coil designs provided a step-change in scanner performance, increasing the speed of image acquisition and providing access to new contrasts.
He also realised new methods for designing gradient coils on arbitrarily shaped surfaces – a requirement for modern open and multi-modal MRI scanners.
The resulting coil designs and software have been used commercially.
Bowtell also made key contributions to the development of the MRI-based technique of quantitative susceptibility mapping (QSM), which provides access to a new quantitative MRI contrast that is highly sensitive to variations in tissue iron content.
Since excess iron is toxic and iron content is locally disrupted in a range of neurodegenerative diseases, QSM is now being widely applied in research and clinical studies.
The development of QSM is part of Bowtell’s exceptionally broad body of work in pushing the capability of MRI to higher field and diagnostic power.