Pneumonie à Sars-CoV-2 : broncho-pneumonie ou vasculopathie ? Focus sur le signe scanographique du « vaisseau élargi » et corrélations radio-histologiques

INTRODUCTION: The Sars-CoV-2 pandemic has started a year ago, and to this day, the pathophysiology of lung parenchymal lesions is not fully understood. Chest-CT is an essential diagnostic and prognostic tool to evaluate the disease, and findings of Covid-19 pneumonia are well established. However, vascular abnormalities have been reported in a vast majority of patients, such as irregularities and enlargement of the distal pulmonary vessels, and they are not yet well-known or recognised by most radiologists. RECENT FINDINGS: Histological studies have shown vascular mural infiltration and multiple abnormalities of the pulmonary vasculature. These can be correlated to the chest-CT findings, and may raise the diagnosis of Covid-19 pneumonia when there is a biological doubt or progression of ground-glass opacities of unknown origin. They suggest that the alveolo-interstitial lesions, which are not associated with bronchial abnormalities, could be secondary to the vascular damages. Further studies are necessary to evaluate the prognostic value of the extent of pulmonary vascular abnormalities on chest-CT. CONCLUSION: This work correlates the radiological and the histological findings of pulmonary vascular lesions in Sars-Cov-2 pneumonia and provides an extensive iconography of the main encountered abnormalities.