Purpose.

Assessment the state of the lungs using CT in the dynamic follow-up of patients who have suffered from viral COVID-19 pneumonia in the delayed period after 6-10 months, and to identify the relationship of residual lung changes with the clinical condition and results of external respiratory function (ERF).

Materials and methods. We examined 78 patients who had suffered from bilateral polysegmental viral COVID-19 pneumonia in April-May 2020, using multi-spiral computed tomography (CT) of the lungs. All patients had a medical history, performed CT scans of the lungs in the acute and delayed (6-10 months after hospitalization) phases, and a study of FVD in the delayed phase. The analysis of a series of tomograms of the lungs in dynamics was carried out. We developed an severity score of the lung condition (LungSS), expressed in the total score, which was calculated based on the score of typical patterns characteristic of viral Covid19-pneumonia, as well as residual changes and areas of fibrosis. LungSS was calculated for each patient in the acute and delayed follow-up periods.

Results. The present study shows the dynamics of lung changes in the delayed period 6-10 months after the viral Covid19-pneumonia. Residual lung changes were detected in 66 people (84,6%). Of these, 35,9% of patients have areas of fibrosis, but most of the residual changes are linear and small-nodular seals (76,9%). The frequency of detection of residual reticular changes and consolidation was low (15,3%, 1,3%, respectively). Attention is drawn to the relatively frequent detection of areas of "Ground-glass opacity "(10,8%). In patients with severe and critical course of viral Covid19-pneumonia (CT3 and CT4), LungSS in the delayed follow-up period did not significantly differ from that in patients with mild and moderate course (CT1 and CT2) of the disease (4,5 [0,22], 2,5 [0,16], accordingly, p=0,61). There was no significant correlation between the detected residual lung changes in the delayed period and ERF.

Conclusion. In a significant part of patients (84,6%) who have suffered from COVID-19 viral pneumonia, residual changes in the lung parenchyma persist, mainly in the form of linear seals and to a lesser extent fibrosis. These changes did not have a reliable relationship with the results of the FVD. LungSS proposed in this study reflects the dynamic picture of lung changes in the acute and delayed period, and can be a good indicator for monitoring patients who have suffered from COVID-19 viral pneumonia.