Comparison of ultrasound signs, computed tomography data and morphological examination of the lungs in patients with coronavirus infection: post hoc analysis

Abstract

INTRODUCTION: Ultrasound examination (US) of the lungs has shown high efficiency in the diagnosis of COVID-19 pneumonia. The aim of the research was studying the correspondence of computed tomography (CT) US signs of the lungs and morphological data in patients with COVID-19 pneumonia. MATERIALS AND METHODS: The post hoc analysis included 388 patients who simultaneously underwent ultrasound and CT of the lungs. Lung ultrasound was performed according to the 16-zone “Russian Protocol”. Morphological data were obtained from the results of pathoanatomic examination of deceased patients. RESULTS: The comparison of signs detected by CT and ultrasound of the lungs was performed during a multidimensional correspondence analysis. The analysis was carried out using a three-dimensional solution that explained 64.9 % of inertia (p < 0.001). CT signs of “ground glass opacity” (100 %) corresponded to the B-line at ultrasound (100 %), CT of the consolidation sign (44.8 %) — ultrasound signs of consolidation (46.9 %), aerobronchogram of CT (34 %) — aerobronchogram of ultrasound (36.9 %), free liquid CT (11.1 %) — free liquid Ultrasound (13.9 %). CT signs of reticular changes (29.6 %) and “cobblestone pavement” (12.4 %) corresponded to various combinations of ultrasound signs of subpleural consolidation and B-lines. The B-lines were caused by the exudation of fluid and protein molecules into the intraalveolar space against the background of massive death of alveolocytes and formed by the development of intraalveolar edema and the formation of hyaline membranes. The ultrasonic sign of consolidation appeared in the airless zone of the lungs. Subpleural consolidation are caused by thickening and inflammatory infiltration of the pleura, diffuse alveolar damage, with intraalveolar edema, death and decay of alveolocytes, perivascular inflammatory cell reaction/ During treatment for more than 7 days, consolidation in the lung tissue developed due to the disorganization of the organ structure due to the progression of fibrosis. CONCLUSION: Multivariate correspondence analysis showed correlation of CT signs and US signs of the lungs. Morphological analysis showed polymorphism of histological data that caused the formation of ultrasound signs.