Relation of impulse oscillometry and spirometry with quantitative thorax computed tomography after COVID-19 pneumonia.

After COVID-19, forced vital capacity, reactance area, resonant frequency, and X5 correlated with the percentages of density range volumes of ground-glass opacity areas in the quantitative computed tomography. X5 was the only parameter correlated with density ranges consistent with both ground-glass opacity and fibrosis. Furthermore, the percentages of forced vital capacity and X5 were shown to be associated with the perception of dyspnea.