CT Scans May Identify COVID-19

Scans typically used to diagnose strokes are showing physical signs in the lungs that identify COVID-19.

New findings have shown that COVID-19 may be diagnosed using the same emergency scans intended to diagnose stroke. This discovery has important implications in the management of patients presenting with suspected stroke.

Study lead and Senior Lecturer in Neuroimaging at King's College London, Tom Booth, said the emergency scans captured images of the top of the lungs where a fluffiness known as 'ground glass opacification' allowed COVID-19 to be diagnosed.

225 patients were examined from 3 London Hyper-Acute Stroke Units. The emergency stroke scan consisted of a computed tomography (CT) of the head and neck blood vessels.

“Apical ground-glass opacification was present in 22.2% (50/225) of patients. Ground-glass opacification had high interrater reliability (Fleiss κ&thinsp;= 0.81; 95% CI, 0.68—0.95) and, compared with reverse-transcriptase polymerase chain reaction, had good diagnostic performance (sensitivity, 75% [95% CI, 56–87]; specificity, 81% [95% CI, 71–88]; OR = 11.65 [95% CI, 4.14–32.78]; P&thinsp;<&thinsp;.001) on multivariate analysis,” wrote the investigators.

He added the results show that when the team saw these changes in the top of the lungs during the emergency scan, they were able to reliably and accurately diagnose COVID-19 and the changes also predicted increased mortality.

"This is particularly relevant given the limitations of currently available Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) reverse transcriptase-polymerase chain reaction (RT-PCR) testing as it takes time to complete the test and sometimes it is inaccurate," Booth said. "Additionally, our data have prognostic information given the increased mortality in those with lung changes shown in our cohort. These are useful results because the changes are simple for radiologists and other doctors to see. This is "free information" from a scan intended for another purpose yet extremely valuable."

The findings were published in the American Journal of Neuroradiology.

"Our findings have important implications in the management of patients presenting with suspected stroke through early identification of COVID-19 and the subsequent limitation of disease transmission," the investigators concluded.