Ct in patients with covid-19: Imaging patterns, disease extent and evolution;our experience in a Greek reference university hospital

Purpose: To present our experience from a large Greek reference University Hospital regarding the imaging patterns, severity and evolution of disease, in patients hospitalised with laboratory-confirmed COVID-19 infection. Material and Methods: 79 consecutive reverse transcription polymerase chain reaction (RT-PCR) confirmed COVID-19 infected patients undergoing chest CT at our hospital between 03/03/2020 and 10/05/2020 were included in the study. All initial scans were evaluated for the presence of various imaging findings and their distribution, as well as for disease extent/severity using the Covid Visual Assessment Scale. Follow-up CTs acquired in 14 of these patients were also examined in order to estimate disease evolution. Results: The most typical imaging findings were bilateral (86%), multilobar (92.4%) ground glass opacities (GGOs) ± consolidations (89.9%), GGOs with concomitant intralobular or interlobular thickening (crazy paving pattern) (53.1%) and subpleural line(s)/band(s) (55.7%), most often distributed peripherally (77.2%), posteriorly (55.7%) and in the lower zones (49.4%). Common findings included bronchial wall thickening (39.2%), bronchial dilatation (40.5%), vascular enlargement (46.8%), pleural thickening (32.9%) and air bronchogram(s) (29.1%). Less common findings were lymphadenopathy (25.3%), pleural effusion(s) (19%) and nodule(s) (20.2%). Most patients suffered from a mild (<25%) to moderate (<50%) imaging extent of disease. Increase in extent of disease was seen in 10/14 (71.4%) patients, with increase of both consolidations and GGOs seen in 8/10 (80%) of these patients. Conclusions: Our findings further confirm formerly published radiological patterns of COVID-19 pneumonia and raise awareness regarding the prevalence of subtler findings such as the frequently occurring subpleural line(s)/band(s) more often noted in this study than previously described. Further research is necessary in order to detect a possible connection between certain imaging findings, clinical status, disease severity and outcome.