Variability of computed tomography angiography coverage of lung parenchyma in acute stroke.

BACKGROUND

Computed tomography angiography (CTA) of the head and neck during acute ischemic stroke (AIS) usually includes visualization of lung apices. The possibility to evaluate for pulmonary changes, e.g. peripheral ground-glass and consolidative opacities suggestive of coronavirus disease 2019 (COVID-19)-related pneumonia, depends on the area of the lung covered by CTA.

METHODS

We performed an analysis of a real-world scenario assessing the variability of lung coverage on CTA in patients presenting with AIS to a comprehensive stroke center (CSC) or to one of eight primary stroke centers (PSC) within a teleradiological network covered by the comprehensive stroke center in 2019.

RESULTS

Our final analysis included n = 940 CTA, and in n = 573 (61%) merely lung apices were covered. In 19/940 (2%) of patients no lung tissue was covered by CTA. CTA scanning protocols in the CSC began significantly more frequently at the level of the ascending aorta (CSC: n = 180 (38.2%), PSC: n = 127 (27.1%), p-value < 0.001) and the aortic arch (CSC: n = 140 (29.7%), PSC: n = 83 (17.7%), p-value < 0.001), and by this covered less frequently the lower lobes compared to CTA acquired in one of the PSC.

CONCLUSIONS

In our pre-COVID-19 pandemic representative stroke patient cohort, CTA for AIS covered most often only lung apices. In 37% of the patients CTA visualized at least parts of the lower lobes, the lingula or the middle lobe allowing for a more extensive assessment of the lungs.