IBME hosts second Bellhouse BioEngenuity Keynote Lecture

The Keynote Lecture, titled “Making Waves: Probing the Structural Dynamics of the Human Brain with MRI and MRE” was delivered by Professor Philip V. Bayly, Lee Hunter Distinguished Professor of Mechanical Engineering at Washington University, U.S.A. Prof Bayly’s research assesses the mechanical response of the brain to loading in sports, accidents, and other scenarios. Data from various sources, including magnetic resonance imaging (MRI) and magnetic resonance elastography (MRE) were combined to build mechanical models for prediction of TBI and enable researchers to develop countermeasures to forces experienced during impacts, deceleration, and oscillation.

To understand the effects of head impacts, tagged MRI was used to image brain movement and estimate deformation (strain). New observations of the brain’s natural frequencies and fundamental modes of oscillation were presented. To estimate the brain’s mechanical properties, candidate parameter values were used in repeated training of models until predictions matched observations. A 3D printed hydrogel material that behaves like a brain for modelling purposes was presented as a valuable tool for validation. Various hypotheses for cortical folding and folding mechanisms of the brain during development were reviewed. The use of punch biopsies and measurement of deformation of excised brain tissue was described as a methodology for inferring the stress state of the brain. The keynote presentation thus delivered a detailed overview of the use of imaging technology for understanding the mechanics and material properties of biological tissues and cells. 

The keynote lecture was preceded by two talks from leading Oxford researchers. Professor Holly Bridge from the Oxford Centre for Integrative Neuroimaging opened the event with the lecture titled, “Using Multi-Modal Magnetic Resonance Imaging to Understand Rehabilitation of the Visual System Following Stroke.” She described how MRI is used to understand the damage to the visual cortex after a stroke. This is especially important for younger patients, as it has implications for both driving and sports performance. The importance of the motion sensitive area of the brain for retaining some visual ability after stroke was highlighted with data from diffusion and functional MRI presented, alongside MRI spectroscopy. Her research demonstrated that targeted training, such as motion discrimination exercises, could significantly improve visual function over six months. This improvement after training was accompanied by an increase in the quality of white matter of the visual system, measured with diffusion MRI. Changes in the neurotransmitter GABA were inversely correlated with visual performance improvements following treatment, suggesting it has a role in boosting vision.

The findings underscored the importance of early intervention and engaging rehabilitation strategies. They also offered a concrete option to patients in an area characterised by a lack of clinically available rehabilitation strategies. Pharmacological treatment alongside rehabilitation exercises may offer additional options for improvement but further research is required.

Professor Antoine Jerusalem from the Department of Engineering Science followed with the presentation titled, “From Mechanical Integrity to Brain Injury in Assaults: The Case for AI-Mechanical Coupling”. He highlighted the complexity of categorising TBI and the limitations of traditional mechanical metrics. His research uses computational mechanics coupled to artificial intelligence (AI) to address challenges around both subject-specific and structural integrity considerations when studying TBI. Prof Jerusalem reviewed the development of head, hand, and neck models for impacts of TBI. By calculating the deceleration and rotational forces in simulations of head impacts using these models, maximum stress, pressure, and strain to different regions of the brain could be determined. AI can then be used to interpret these metrics in the context of a variety of head injuries for a particular individual, unlike traditional approaches aimed at establishing thresholds for a wide range of the population. Through this approach, a personalised predictive advanced numerical framework could be developed. By integrating mechanical computation with AI predictions, the framework achieved higher accuracy in predicting outcomes. This novel methodology may ultimately improve how TBIs are characterised and offer insights for prevention and treatment.

After the talks all attendees were welcomed to a buffet lunch to interact with each other and also to visit research posters from DPhil students and post-doctoral researchers in Biomedical Engineering. Thalia Seale, a doctoral researcher who presented a poster on cardiac motion and generative models, reflected on the value of the event: “I found the talks incredibly useful and inspiring for my work because I use data-driven simulations in my study of hearts. The combination of computationally intense models and mechanistic problem-solving will be a key to obtaining accurate results in future clinical research.”

Dr Ryman Hashem, a Senior Researcher at the Podium Institute, reflected on the applicability of the keynote lecture to his own research, “The Keynote provided helpful ideas for simulating the brain inside the skull and information on the material properties of the brain. It was especially helpful to understand the complexity of the models presented. The information presented aligns closely with current research taking place at the Podium Institute and will inform our next steps, including the validation of our own models.”

The event was attended by approximately 100 people from the Departments of Engineering Science and Clinical Neurosciences, the wider Oxford community, and external researchers. Director of the Institute of Biomedical Engineering, Professor Robin Cleveland, said “The event encapsulated the vision of Prof Brian Bellhouse in bringing together world experts from medical sciences and engineering sciences together to address a problem of huge societal impact. I would like to thank the speakers for giving clear and inspiring talks, the audience for being so engaged and asking perceptive questions, and the IBME administrative team for superb organisation to make the event run so smoothly.”

The biannual BioEngenuity event is made possible through a generous endowment by the family of Prof. Brian Bellhouse and serves an important function of providing training and networking opportunities to early career researchers in biomedical engineering. Each event combines a keynote presentation with Oxford University faculty research talks and a poster session highlighting the research contributions of post-doctoral researchers and doctoral students.