Coronavirus: study finds abnormality in lungs of patients with long Covid
Sylvie Claire / January 31, 2022
In a new study, Oxford University radiology professor Fergus Gleeson used a noble gas called xenon to reveal abnormalities in the lungs of patients treated with long Covid who continued to suffer from breathlessness. This method has now made it possible to detect these abnormalities when CT scans and lung tests appeared normal.
Thirty-six subjects, divided into three groups, were asked to lie down in an MRI scanner and inhale a liter of xenon gas that had been treated so that it could be detected by the scanner. This gas can be safely inhaled and behaves like oxygen. This allowed the radiologists to see how xenon moved from the lungs into the bloodstream.
The first group included patients with long Covid who had been tested previously and had a normal CT scan. In the second group, there were corona patients who had been hospitalized at least three months before, who did not have long Covid and whose CT scan was (almost) normal. And finally a control group of people who had not been hospitalized because of the virus and who did not suffer from long Covid.
It then became apparent that patients with long Covid appeared to have significantly reduced gas transfer from the lungs to the bloodstream. Although their CT scans were normal, xenon MRIs detected similar abnormalities in them, Professor Gleeson explains. These people had not been through any serious illness or been hospitalized. Some of them had been suffering from long-term symptoms for a year.
This pilot study, funded by the UK government, now needs to be reviewed and validated by other experts. Further research also needs to be done to determine how this abnormality appears and how many patients with long Covid have such abnormal scans. A larger study with about 400 participants will now follow to try to provide these answers.