Dr Michael Stringer
Stroke Association Research Fellow in MRI, Medical Physicist
- Centre for Clinical Brain Sciences
- Edinburgh Imaging
- Edinburgh Neuroscience
Contact details
- Email: m.stringer@ed.ac.uk
Address
- Street
-
University of Edinburgh, Centre for Clinical Brain Sciences
Chancellor's Building, 49 Little France Crescent, - City
- Edinburgh
- Post code
- EH16 4SB
Background
I am a Stroke Association research fellow in magnetic resonance imaging at the Centre for Clinical Brain Sciences, University of Edinburgh working with Prof Joanna Wardlaw and Dr Michael Thrippleton. My current work focuses on improving the accuracy and sensitivity of in vivo measurements of vascular dysfunction, and applying them across several studies on patients with small vessel disease, which causes many strokes and dementias. Originally from a mathematics background (BSc (Hons) Glasgow, MSc Heriot-Watt), I previously completed a PhD in medical imaging at the University of Aberdeen in 2016.
Qualifications
PhD in Medical Sciences, University of Aberdeen
MSc in Applied Mathematical Sciences, Heriot-Watt University
BSc(Hons) in Pure Mathematics, University of Glasgow
Responsibilities & affiliations
Committees
UK Dementia Research Institute, Early Career Researcher day planning committee for Connectome 2023 (annual internal meeting)
UK Dementia Research Institute, Vascular theme committee
Edinburgh Imaging, MR Safety committee
Memberships
International Society for Magnetic Resonance in Medicine (Member)
Institute for Physics and Engineering in Medicine (Member)
Higher Education Academy (Associate Fellow)
Undergraduate teaching
I have previously demonstrated for labs in Biology and Exercise Physiology while pursuing my PhD at the University of Aberdeen.
Postgraduate teaching
I currently tutor for the Applications in Disease Research and Clinical Applications modules for the Edinburgh Imaging MSc programme and Neuroimaging Research for Neuroscience Graduates, part of the Integrative Neuroscience and Stem Cells and Translational Neurology Masters programme.
Current PhD students supervised
I am a supervisor for Keelin Ridge (Keelin Ridge | The University of Edinburgh) and Grant Kirkwood (both 1st year).
Past PhD students supervised
I was a co-supervisor for Emily Sleight (now a postdoc at EPFL) on the project "Advanced signal processing and MRI to assess cerebrovascular health in small vessel disease and dementia" which implemented and assessed novel approaches for calculating cerebrovascular reactivity using MRI.
Research summary
Developing and using quantitative MRI methods to assess haemodynamic and metabolic properties in patients is my main research focus. Embedded within a clinical group I have played a leading role in several multicentre imaging studies (e.g. H2020 funded SVDs@Target, Leducq Network for Research Excellence on perivascular spaces), including clinical trials (LACI-1 and Treat-SVDs), cross-sectional (Sleep Apnea and Investigate-SVDs) and longitudinal studies (Mild Stroke Study 3).
My research covers three main strands:
- Methodological development: Cerebrovascular reactivity (CVR) is an important haemodynamic measure of how well blood vessels open and close, particularly in diseases such as small vessel disease (SVD) which causes many cases of stroke and dementia. Using blood oxygen level dependent (BOLD) MRI it is possible to measure CVR in the brain. However, there are several technical challenges to developing more accurate measurements. In a recent systematic review, we highlighted the heterogeneity in acquisition and analysis methods used to date, and that there was a need for greater validation. Following this, we conducted a healthy volunteer study where we found processing CVR using region- and voxel- based measures of CVR influenced the resulting values, while in poorer quality data the delay, a measure of how long the blood vessels take to respond, depended on the allowed range of values. Currently, I am working to develop this findings further with a new PhD student starting in September focused on developing improved measures of delay and two Masters students who will work to quantify the effect of venous contamination on tissue-based CVR values and assess partial volume correction strategies. Beyond my interests in CVR methodology, I have also been involved with work assessing methods of blood-brain barrier permeability using both dynamic-contrast enhanced MRI and arterial spin labelling based methods developed by collaborators at the University of Southern California in a pilot study, as well as phase contrast based measures of blood and CSF pulsatility.
- Clinical studies in stroke and small vessel disease: I have worked across several multicentre international studies. As a member of the SVDs@Target collaboration, I trained and advised other sites on setting up CVR experiments locally, led imaging quality assurance, managed imaging data transfer, calculated CVR (>450 scans) for Investigate-SVDs and the Treat-SVDs clinical trial (primary outcome measure), for which I also developed a computational method to extract and harmonise summary blood pressure measures (secondary outcome). Through the Leducq network on perivascular spaces, a key indicator of SVD, I worked closely with collaborators at Sunnybrook Health Sciences Centre to establish a harmonised imaging protocol for studies on SVD and sleep apnoea, was heavily involved with data acquisition and the establishment of image processing pipelines, some of which were handed over to students I supervised and which have since been used across several publications. Through these studies, we hope to learn more about what causes SVD and the resultant brain damage, which often leads to strokes, which may ultimately help develop novel treatments. Indeed, through the LACI-1 and Treat-SVDs trials we have shown the potential of imaging based biomarkers to assess the efficacy of different pharmaceutical agents in vivo.
- Improving translational imaging: Through the Leducq network, I led a multicentre systematic literature review aiming to assess how rodent and clinical imaging protocols are implemented in SVD which made several recommendations to improve translation. In particular, it indicated the importance of harmonising the scans acquired in clinical and preclinical studies where possible, and the need to develop clinically viable approaches to assess brain waste clearance. Building on these links, I was able to visit collaborators at Yale and the University of Southern California with funding from SINAPSE to learn more about advanced preclinical imaging approaches and developed an independent Leducq-funded pilot project assessing novel blood-brain barrier leakage markers with parallel preclinical histological validation which is currently on-going. I was also a co-investigator on a British Heart Foundation-funded project using MRI to help characterise a novel rat model of SVD (Atp11-Beta), developed by Prof Anna Williams and her group.
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Blood-brain barrier leakage hotspots collocating with brain lesions due to sporadic and monogenic small vessel disease
In:
Journal of Cerebral Blood Flow and Metabolism, pp. 0271678X2311734
DOI: https://doi.org/10.1177/0271678X231173444
Research output: Contribution to Journal › Article (Published) -
Cerebrovascular reactivity measurements using 3T BOLD MRI and a fixed inhaled CO2 gas challenge: Repeatability and impact of processing strategy
In:
Frontiers in physiology, vol. 14
DOI: https://doi.org/10.3389/fphys.2023.1070233
Research output: Contribution to Journal › Article (Published) -
Corrigendum: Cerebrovascular reactivity measurement using magnetic resonance imaging: A systematic review
In:
Frontiers in physiology, vol. 13, pp. 1105285
DOI: https://doi.org/10.3389/fphys.2022.1105285
Research output: Contribution to Journal › Article (Published) -
The EffecTs of Amlodipine and other Blood PREssure Lowering Agents on Microvascular FuncTion in Small Vessel Diseases (TREAT-SVDs) trial: Study protocol for a randomised crossover trial
In:
European Stroke Journal, pp. 239698732211435
DOI: https://doi.org/10.1177/23969873221143570
Research output: Contribution to Journal › Article (E-pub ahead of print) -
Retinal capillary microvessel morphology changes are associated with vascular damage and dysfunction in cerebral small vessel disease
In:
Journal of Cerebral Blood Flow and Metabolism
DOI: https://doi.org/10.1177/0271678X221135658
Research output: Contribution to Journal › Article (E-pub ahead of print) -
CADASIL Affects Multiple Aspects of Cerebral Small Vessel Function on 7T-MRI
In:
Annals of Neurology
DOI: https://doi.org/10.1002/ana.26527
Research output: Contribution to Journal › Article (E-pub ahead of print) -
Associations of Peak-Width Skeletonized Mean Diffusivity and Post-Stroke Cognition
In:
Life, vol. 12, pp. 1362
DOI: https://doi.org/10.3390/life12091362
Research output: Contribution to Journal › Article (Published) -
Deep attention super-resolution of brain magnetic resonance images acquired under clinical protocols
(30 pages)
In:
Frontiers in Computational Neuroscience, vol. 16
DOI: https://doi.org/10.3389/fncom.2022.887633
Research output: Contribution to Journal › Article (Published) -
Topological relationships between perivascular spaces and progression of white matter hyperintensities: A pilot study in a sample of the Lothian Birth Cohort 1936
(17 pages)
In:
Frontiers in Neurology, vol. 13
DOI: https://doi.org/10.3389/fneur.2022.889884
Research output: Contribution to Journal › Article (Published) -
Loss of the heterogeneous expression of flippase ATP11B leads to cerebral small vessel disease in a normotensive rat model
In:
Acta Neuropathologica, vol. 144, pp. 283-303
DOI: https://doi.org/10.1007/s00401-022-02441-4
Research output: Contribution to Journal › Article (Published)