Research by Oxford and Sheffield Universities is the first in Europe to use hyperpolarised xenon gas with MRI scanning to identify the impact on lung function as patients recover from COVID-19, when standard MR and CT scans may be normal.
Professor Fergus Gleeson, Professor of Radiology at the University of Oxford, is collaborating with Professor Jim Wild, Professor of MR Physics at the University of Sheffield, to investigate possible reasons for patients remaining short of breath following treatment for COVID-19 pneumonia, even after discharge.
They are working with an initial group of 40 patients in Oxford and Sheffield over the next six months. So far, the hyperpolarised xenon MRI technique has identified weakened lung function in all patients who have taken part in the study – this damage to lungs from COVID-19 is not visible on a standard MRI or CT scan.
Professor Gleeson, a consultant radiologist at Oxford University Hospitals NHS Foundation Trust and the University of Oxford's head of academic radiology, said: "We may be getting an insight into why some patients have symptoms long after they have left hospital, and when other tests are normal. This may help us identify patients that may potentially benefit from treatment even after discharge, for example with steroids or other therapies."
Hyperpolarised xenon MRI is is unique in its ability to measure gas transfer in the lungs with imaging and identify where the damage caused by COVID-19 pneumonia has occurred.
The study follows up patients for six months after leaving hospital. Early data suggests that the ability to transfer oxygen from the lungs into the blood stream when breathing is visibly impaired for some time, even after hospital discharge following COVID-19 pneumonia.
This reduction in the function of the lungs can be detected in this research study, and may be an explanation for some patients experiencing persistent symptoms even with seemingly 'normal' results from standard GP and hospital tests.
The striking early results have resulted in discussions to expand the study to involve more patients in the community, to identify the overall prevalence of lung damage and the speed of recovery from this virus. Prof Gleeson is now working with clinicians providing follow-up services for patients post COVID-19 pneumonia to identify further patients feeling long-term ill health after COVID-19 who may wish to join the study.
Professor Wild, Head of Imaging and NIHR Research Professor of Magnetic Resonance Physics at University of Sheffield, said: "Hyperpolarised xenon MRI offers a unique means of imaging impairment to oxygen uptake in the lungs caused by COVID-19 infection and its after effects. In other fibrotic lung diseases we have shown the methods to be very sensitive to this impairment and we hope the work can help understand COVID-19 lung disease."
The study is funded by the NCIMI and the University of Oxford, and supported by the NIHR Oxford Biomedical Research Centre. It will be linked to the big national clinical follow-up study PHOSP-COVID.
If you are interested in this study, please contact ncimi@oncology.ox.ac.uk