CT angiography for ischemic stroke accurate in COVID-19 screening
Lung evaluation by CT angiography is accurate for fast and early detection for COVID-19 infection in patients with acute ischemic stroke, researchers reported.
“CTA of the head and neck done during emergency evaluation for large vessel occlusion typically includes visualization of lung apices, providing the first objective screen for peripheral ground-glass and consolidative opacities suggestive of COVID-19-related pneumonia,” Charles Esenwa, MD, MS, assistant professor and stroke neurologist at the Albert Einstein College of Medicine, and colleagues wrote.
The retrospective analysis, published in Stroke, included 57 patients with CTA of the head and neck presenting with acute ischemic stroke at three Montefiore Health System hospitals in Bronx, New York, who were screened for COVID-19 using real-time reverse transcription polymerase chain reaction from March to April.
Researchers used CT to evaluate lung apices for signs of COVID-19 pneumonia and assessed its accuracy alone and combined with patient-reported symptoms such as cough and/or shortness of breath.
In total, 30 patients tested positive for COVID-19 and 27 tested negative. In those positive for COVID-19, 67% had lung findings highly or very suspicious for COVID-19 pneumonia compared with 7% of patients negative for COVID-19 infection (P < .001). Self-reported clinical symptoms of cough or dyspnea were reported by 13 patients positive for COVID-19, five of whom did not have evidence of COVID-19 on CT angiography apical lung assessment.
When evaluated alone, CTA apical lung assessment showed a sensitivity of 0.67, a specificity of 0.93, a positive predictive value of 0.19, a negative predictive value of 0.99 and accuracy of 0.92 in diagnosing COVID-19 in patients with acute ischemic stroke. In combination with patient-reported symptoms, CTA apical lung assessment sensitivity improved to 0.83.
According to a press release, diagnostic accuracy may have been higher due to the patients living in an area with elevated incidence of COVID-19 infection.
“Screening questionnaires alone are often inaccurate because of the absence of symptoms or the patient is unable to speak because they are suffering from an acute stroke,” Esenwa said in the release. “Early diagnosis via CT scans has helped our center protect other patients and staff through early isolation and it has also allowed use to start early supportive care for those suspected of having stroke who are COVID-19 positive.”