Researchers from the Universities of Oxford and Sheffield found that the lungs of some Covid-19 patients whose CT scan showed no damage were still showing damage. And for a period of at least three months after their discharge from the hospital.
Researchers evaluated the damage using a new, cutting-edge imaging method, hyperpolarized magnetic resonance xenon scans. In doing so, they allowed patients to inhale a small amount of xenon, a harmless gas that behaves like oxygen in the lungs. But when oxygen cannot be seen in the lungs on regular MRI scans, so is xenon.
According to lead investigator Fergus Gleason, professor of radiology at the University of Oxford, follow-up scans with hyperpolarized magnetic resonance xenon show that there are indeed abnormalities that are not visible on regular scans. The abnormalities prevent oxygen from entering the bloodstream properly throughout the lungs.
Researchers are now starting to test Covid-19 patients who are not hospitalized but who have long-term shortness of breath. Initial results show that some of them have similar abnormalities in their lungs. According to Gleason, a larger study is needed to determine how often this occurs and how long it takes for improvement.
