BACKGROUND: To retrospectively analyze the evolution of clinical features and thin-section CT imaging of novel coronavirus pneumonia (COVID-19) in 17 discharged patients. METHODS: Serial thin-section CT scans of 17 discharged patients with COVID-19 were obtained during recovery. Longitudinal changes of clinical parameters and CT pattern were documented in all patients during 4 weeks since admission. CT score was used to evaluate the extent of the disease. RESULTS: There was a marked improvement of fever, lymphocytes count, C-reactive protein and erythrocyte sedimentation rate within the first two weeks since admission. However, the mean CT score rapidly increased from the 1(st) to 3(rd) week, with a top score of 8.2 obtained in the 2(nd) week. During the 1(st) week, the main CT pattern was ground-glass opacities (GGO,76.5%). The frequency of GGO (52.9%) decreased in the 2(nd) week. Consolidation and mixed patterns (47.0%) were noted in the 2(nd) week. Thereafter, consolidations generally dissipated into GGO and the frequency of GGO increased in the 3(rd) week (76.5%) and 4(th) week (71.4%). Opacities were mainly located in the peripheral (76.5%), subpleural (47.1%) zones of the lungs, and presented as focal (35.3%) or multifocal (29.4%) in the 1(st) week and became more diffuse in the 2(nd) (47.1%) and 3(rd )week (58.8%), then showed reduced extent in 4(th )week (50%). CONCLUSIONS: The progression course of CT pattern was later than the clinical parameters within the first two weeks since admission; however, there was a synchronized improvement in both clinical and radiologic features in the 4(th) week.
Novel Coronavirus Pneumonia (COVID-19) Progression Course in 17 Discharged Patients: Comparison of Clinical and Thin-Section CT Features During Recovery