Clinical applications of 7T MRI: epilepsy, mitochondrial disease, glioblastoma and heart failure

Abstract: 

Ultra-high field (7T+) MRI is emerging from being a topic of interest to MRI physicists into a genuinely clinical imaging modality. 7T offers exquisite sub-millimetre spatial resolution and sensitivity to subtle changes in tissue contrast. Yet conventional single transmit 7T MRI was hampered by signal voids that often obscure significant parts of the brain, which is clearly unacceptable for diagnostic imaging when the locus of disease is unknown. New parallel transmit methods offer high-fidelity whole-brain imaging, which since 2024 is available with UKCA/CE/FDA approvals for diagnostic imaging on Siemens new Terra.X scanners. In this seminar, I describe recent translational clinical studies at Cambridge and the method developments that were needed to facilitate them. These include a study applying parallel transmit 7T MRI for pre-surgical assessment of patients with severe epilepsy whose previous clinical 3T and FDG-PET had been inconclusive. PTx-7T MRI changed clinical management to the benefit of 56% of our first 31 patients. Per lesion detected, it is 10x cheaper than alternative invasive stereotactic EEG investigations, not to mention being safer and more convenient. I am now setting up the world’s first multisite prospective trial of 7T MRI for epilepsy pre-surgical evaluation in collaboration with King’s College London to assess the health economic case for NHS adoption of 7T MRI in epilepsy. Another ongoing study “DefINe” is applying R2* mapping techniques validated in the UK7T Network’s travelling heads study as the primary endpoint for a CTIMP trial evaluating whether the drug deferiprone can be repurposed to treat patients with the rare mitochondrial disease neuroferritinopathy which causes inevitable incurable dementia in the 40s. As well as these 1H-MRI imaging studies, I describe our recent work developing quantitative deuterium metabolic imaging for applicants in cancer and neurodegeneration, and ongoing studies assessing regional cellular energy metabolism by phosphorus MRSI in the heart and brain. 

Bio: 

Prof Chris Rodgers leads the 7T MRI physics group at Cambridge. He originally read chemistry MChem at Oxford. He then studied the effects of magnetic fields on chemical reactions during his DPhil in Physical Chemistry at Oxford. From 2008-2017 he worked at OCMR on cardiac phosphorus spectroscopy. He was one of the first users of the Oxford 7T, building a whole-body 31P birdcage coil to enable cardiac energetic assessment for each separate coronary perfusion territory and implementing early parallel transmit cardiac ¹H imaging methods. Now, his Cambridge group focus on clinical translation of 7T MRI technology and on developing novel methods to facilitate that. In the last few years, he has contributed to 7T studies in patients with epilepsy, dementias, rare mitochondrial diseases, stroke, and COVID-19. His MRI physics method development work includes innovations in algorithms for large-tip angle parallel transmit pulse design and sequences that employ these (diffusion, TSE). He develops methods for metabolic imaging with deuterium, phosphorus and proton MRS(I) in the brain, and continues to develop cardiac phosphorus methods to understand the mechanisms of heart failure. Chris is grateful to work in the UK 7T community, which has been marked from the start by an open and collaborative attitude to science. He would welcome any suggestions for new collaborations whether that is to apply Oxford methods to Cambridge patients, or to share our methods for applications at Oxford, or something else!