The caliber of segmental and subsegmental vessels in COVID-19 pneumonia is enlarged: a distinctive feature in comparison with other forms of inflammatory and thromboembolic disease

Abstract Objective: to compare COVID-19 patients’ vessel caliber with that of normal lungs and lungs interested by other inflammatory and thromboembolic processes. Methods: between March and April 2020, 42 patients affected by COVID-19 pneumonia [COV-P] underwent a CT scan of the lung at Verona University Hospital for clinical indications. Lung images were compared to 4 different groups of patients (normal lung [NL], distal thromboembolism [DTE], bacterial and fungal pneumonia [Bact-P, Fung-P]) by a 4-year-experienced radiologist. Results: COV-P patients’ segmental and subsegmental vessels, as evaluated as the ratio with the corresponding bronchial branch (V/B ratio) were larger with respect to NL, DTE in the apparently healthy parenchyma, a result confirmed in the zones of opacification with respect to Bact-P and Fung-P. Conclusions: This is the first study to comparatively showing that segmental and subsegmental COVID-19 patients’ vessel caliber is significantly enlarged. This is a distinctive feature of COVID-19 pneumonia suggesting distinct pathophysiology as compared to other inflammatory and thromboembolic diseases and alerting radiologists to consider it when evaluating CT scan of suspected patients.