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Patient demographics, length of hospital stay, intensive care unit admission rate, and clinical and laboratory features of acute infection were also included. The scans were obtained on a median of 72.5 days after onset of symptoms (interquartile range: 58.5\u201386.5) and at least 30 days after hospital discharge. Thin-section CT findings included ground-glass opacity, mosaic attenuation pattern, consolidation, traction bronchiectasis, reticulation, parenchymal bands, bronchial wall thickening, and air trapping. We used a quantitative score to determine the degree of air trapping in the expiratory scans.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>Parenchymal abnormality was found in 50% (24\/48) of patients and included air trapping (37\/48, 77%), ground-glass opacities (19\/48, 40%), reticulation (18\/48, 38%), parenchymal bands (15\/48, 31%), traction bronchiectasis (9\/48, 19%), mosaic attenuation pattern (9\/48, 19%), bronchial wall thickening (6\/48, 13%), and consolidation (2\/48, 4%). The absence of air trapping was observed in 11\/48 (23%), mild air trapping in 20\/48 (42%), moderate in 13\/48 (27%), and severe in 4\/48 (8%). Independent predictors of air trapping were, in decreasing order of importance, gender (<jats:italic>p<\/jats:italic> = 0.0085), and age (<jats:italic>p<\/jats:italic> = 0.0182).<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>Our results, in a limited number of patients, suggest that follow-up with paired inspiratory\/expiratory CT in long-COVID patients with persistent respiratory symptoms commonly displays air trapping.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Key Points<\/jats:title>\n                <jats:p>\u2022 <jats:italic>Our experience indicates that paired inspiratory\/expiratory CT in long-COVID patients with persistent respiratory symptoms commonly displays air trapping.<\/jats:italic><\/jats:p>\n                <jats:p>\u2022 <jats:italic>Iterative reconstruction and dose-reduction options are recommended for demonstrating air trapping in long-COVID patients.<\/jats:italic><\/jats:p>\n              <\/jats:sec>","DOI":"10.1007\/s00330-022-08580-2","type":"journal-article","created":{"date-parts":[[2022,2,28]],"date-time":"2022-02-28T16:02:56Z","timestamp":1646064176000},"page":"4427-4436","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":32,"title":["Air trapping in COVID-19 patients following hospital discharge: retrospective evaluation with paired inspiratory\/expiratory thin-section CT"],"prefix":"10.1007","volume":"32","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7443-1730","authenticated-orcid":false,"given":"Tom\u00e1s","family":"Franquet","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ana","family":"Gim\u00e9nez","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Loren","family":"Ketai","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sandra","family":"Mazzini","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andrea","family":"Rial","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Virginia","family":"Pomar","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pere","family":"Domingo","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2022,2,28]]},"reference":[{"key":"8580_CR1","doi-asserted-by":"publisher","unstructured":"Chung M, Bernheim A, Mei X et al (2020) CT imaging features of 2019 novel coronavirus (2019-nCoV). 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