Collaborators

Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University

Centre for Functional MRI, University of California San Diego

Hotchkiss Brain Institute, University of Calgary

Research Summary

The focus of my research is the development of new techniques to non-invasively image the function of the brain using MRI (Magnetic Resonance Imaging). I specialise in the measurement of aspects of brain physiology that are typically difficult to acquire using any other method. For example, my current EPSRC fellowship was awarded to develop new technologies for measuring oxygen metabolism in the human brain. Conventionally such measurements are performed using PET (Positron Emission Tomography) resulting in exposure to ionising radiation and long acquisition times. Even more importantly the equipment to perform these PET measurements is poorly available in the UK. In contrast 3T MRI is widely available in the NHS. Currently my team are collaborating with clinical colleagues to demonstrate the potential of these techniques in acute stroke, traumatic brain injury and brain tumours.

Development of these new techniques is dependent on gaining a better understanding of the interaction between brain physiology and the MRI signal. This is achieved by developing sophisticated simulation tools to better understand sources of systematic error. Isolating specific aspects of physiology is achieved by sensitising the MRI signal using custom pulse sequences and tightly controlled respiratory stimuli. In the case of the former, I have developed a new asymmetric spin echo (ASE) pulse sequence to measure the reversible transverse relaxation rate R₂′ (GESEPI-ASE), which underpins our technique for measuring resting oxygen metabolism (streamlined-qBOLD). In the case of the latter, I have developed novel shaped respiratory stimuli to produce a rapid protocol for measuring vascular reactivity and provide new information about regional variations in blood arrival time (rapid cerebrovascular reactivity mapping).

Related Links

Imaging Cerebral Physiology Network 

Network of scientists interested in imaging brain physiology using MRI

FMRIB Physics Group 

Focussed on the development of new MRI methodologies

FMRI Physiology Group

A subsection of the FMRIB Physics Group specialising in techniques to quantify multiple aspects of brain physiology

Acute Vascular Imaging Centre (AVIC)

Research into new methods of imaging Stroke through the Acute MRI In Cerebral Ischaemia (AMICI) project