Institute of Neuroscience

Staff Profile

Dr Peter Thelwall

William Leech Reader in Magnetic Resonance Physics

Background

Role

My research centres on the development of innovative MR imaging and spectroscopy methods to characterise the structure, function and physiology of human tissues and organs through non-invasive and repeatable scans. My projects aim to develop reliable and valuable quantitative measurements for implementation in clinical research, and span the intersection of magnetic resonance physics, bioscience and clinical research.

I lead an MRC Developmental Pathways Funding Scheme project to develop lung ventilation imaging methods via 19F-MRI of inhaled tracer gases. I have expertise in the application of multinuclear MRI to clinical research and have a funding portfolio supporting these projects. My studies have involved development of novel 19F, 13C and 7Li methodologies, with resultant performance of preclinical, first in man and patient studies.

I contribute to the management of the Newcastle Magnetic Resonance Centre (NMRC), and the Centre for In Vivo Imaging (CIVI). I am a member of the CIVI executive committee, the NMRC and PET operations committees, and I act as CIVI MR safety specialist.

Background

My introduction to magnetic resonance was at Nottingham University during my undergraduate studies (Biochemistry and Biological Chemistry). My PhD at the Department of Biochemistry, University of Cambridge under Dr Kevin Brindle was in the development of MR spectroscopy and imaging methods for the study of cancer cells in vitro and in vivo. I held a postdoctoral position at the University of Florida under the supervision of Dr Stephen Blackband, developing physical models for the study of tissue water diffusion properties and the development of 13C-MRI methods for in vivo assessment of tissue defences against oxidative stress.

Qualifications

BSc (Hons) - 1995, PhD (Cantab) - 1999.

Positions Held

  • 2009 - present: Reader in Magnetic Resonance Physics, Institute of Cellular Medicine, Newcastle University
  • 2006 - 2009: Lecturer in Magnetic Resonance Physics, Institute of Cellular Medicine, Newcastle University
  • 2000 - 2006: Postdoctoral Research Associate, Department of Neuroscience, University of Florida

Memberships

Member of the International Society for Magnetic Resonance in Medicine

Research

Multinuclear MRI to measure tissue structure, function and metabolism

Imaging lung ventilation properties by 19F-MRI of inhaled tracer gases
We are developing non-invasive and radiation-free methods for imaging lung ventilation properties, using new Magnetic Resonance Imaging (MRI) technologies. Our methods provide quantitative measures with potential for translation to clinical practice.Existing techniques to objectively measure lung ventilation properties have significant limitations. For example, spirometry gives no anatomical information and CT scans incur an ionising radiation dose. There is a pressing need for techniques allowing safe, objective, repeatable and quantifiable measurements of ventilation properties. Whilst hyperpolarised noble gas MRI has demonstrated the value of non-invasive and repeatable imaging-based measures of lung ventilation in clinical research, the requirement for hyperpolarisation equipment and expertise presents a barrier to scaling these technologies to clinical practice.A new approach to MRI of ventilation imaging uses MRI of thermally polarised inhalable gases. This approach explois inert fluorocarbon gases with favourable MR relaxation properties, combined with advanced and optimised MRI scan methodologies, to produce images of an inhaled gas without the need for hyperpolarisation.Our studies seek to develop 19F-MRI of perfluoropropane by testing its ability to quantify ventilation defects, representing a step towards the ultimate goal of implementation in clinical practice. We have brought together a team of MR physicists and clinical academics with longstanding experience of respiratory conditions, MR technical approaches, and translational research. Our projects are investigating reproducibility of 19F-MRI lung ventilation imaging methods and testing their ability to quantify compromised ventilation in patients with respiratory diseases. 
Measurement of liver oxidative stress defences by in vivo 13C-MRS measurement of hepatic glutathione metabolism

Oxidative stress plays a central role in the progression of liver disease. We have developed a novel approach to assess hepatic oxidative stress by measuring glutathione synthesis rate with in vivo 13C magnetic resonance spectroscopy. This translational project has employed preclinical models of hepatic oxidative stress insults to demonstrate feasibility, with progression to first ever human demonstration of this approach in healthy volunteers.

We employ administration of a safe and non-radioactive metabolic tracer, 13C-labelled glycine, coupled with in vivo dynamic 13C-MR spectroscopy to monitor metabolism of this tracer into glutathione and other metabolites. We have demonstrated ability to detect and characterise the impact of acute and chronic oxidative stress insults on glutathione metabolism in carefully controlled preclinical models, and successfully translated the methods to human studies. This work has been published in Hepatology: DOI 10.1002/hep.26925.

Present studies involve application of the methods to the study of patients with liver disease, performed in collaboration with the University of Nottingham.

Imaging lithium content in patients receiving treatment for bipolar disorder

In collaboration with Dr David Cousins, we are developing advanced methods to image the distribution of lithium in patients receiving lithium carbonate as treatment for bipolar disorder. This represents direct MR imaging of a pharmaceutical agent in its target organ, and is aimed at better understanding the mechanisms of action of, and inter-patient variation in response to lithium treatment.

Non-invasive assessment of renal fibrosis by multiparametric MRI

Through studies in patient cohorts with biopsy-proven renal fibrosis we are testing the ability of multiparametric (MR relaxation and microstructural measurements) to determine extent of renal fibrosis without the need for invasive biopsy measurements. We are a member of and contributor to the the UK Renal Imaging Network, and a member of the PARENCHIMA COST action on renal MRI.

Grant funding

  • “MICA: Non-invasive quantitative ventilation imaging by MRI of fluorocarbon gases” - Medical Research Council, Developmental Pathways Funding Scheme. £1.33M (Principal Investigator)
  • “MRI of inhaled fluorocarbon gas to assess lung functional properties: Method development and demonstration in healthy human volunteers” - Monash-Newcastle Partnership, £29K (Principal Investigator)
  • “Imaging lung ventilation by MRI of fluorocarbon gases” - Medical Research Council - Confidence in Concept. £30K (Principal Investigator)
  • “Renal imaging for the detection of fibrosis” - GlaxoSmithKline, £51K (Principal Investigator)
  • "In vivo monitoring of liver oxidative stress by magnetic resonance measurements of glutathione turnover” - Medical Research Council, New Investigator Research Grant. £560K (Principal Investigator)

Partnerships

  • Member of UKRIN: the UK Renal Imaging Network
  • Member of the PARENCHIMA COST action

Esteem indicators

External PhD examiner for Cambridge University, Nottingham University, University of Sheffield and University College London.

Internal PhD examiner for Newcastle University

Reviewer for Proceedings of the National Academy of Sciences, Diabetologia, Magnetic Resonance in Medicine, Journal of Magnetic Resonance Imaging, Magnetic Resonance Imaging, Diabetes Obesity and Metabolism, Physics in Medicine and Biology, British Journal of Pharmacology, and Journal of Neuroscience Methods.

Member of the organising committee for the 2008 British Chapter of the ISMRM meeting, Newcastle, UK.

Teaching

PhD supervision

My research team includes research students enrolled in the Faculty of Medical Science PhD programme

Masters-level teaching

I contribute to the NHS Modernising Scientific Careers Clinical Sciences MSc programmes :

  • Module lead for "MPY8011: Imaging with non-ionising radiation 1" - Medical Physics MSc programme
  • Module lead for "MPY8012: Imaging with non-ionising radiation 2" - Medical Physics MSc programme
  • Lecturer for "MPY8001: Introduction to Medical Physics" - Medical Physics MSc programme
  • Lecturer for "MPY8011: Imaging with non-ionising radiation 1" - Medical Physics MSc programme
  • Lecturer for "MPY8012: Imaging with non-ionising radiation 2" - Medical Physics MSc programme
  • Lecturer for "CRV8011: Respiratory and Sleep Science 1" - Respiratory and Sleep Science MSc programme

Undergraduate research teaching

I host research projects placements for Newcastle University Biomedical Sciences BSc students. Students join my team at the Newcastle Magnetic Resonance Centre for a 10 week full time MRI research project, with the aim of achieving valuable advancement in translational MR research with co-authorship in resultant publications.

Tutor to undergraduate students

I am personal tutor for the Biomedical Sciences BSc programme, providing pastoral support to undergraduate students.


Publications