Chest imaging features of Coronavirus disease 2019 pneumonia: a systematic review and meta-analysis

INTRODUCTION: This study aimed to systematically review the evidence reporting the key imaging findings in confirmed COVID-19 pneumonia. EVIDENCE ACQUISITION: A systematic search for articles reporting the prevalence of imaging findings in patients with COVID-19 pneumonia was conducted in seven databases up to April 10, 2020. The study protocol was registered in PROSPERO (CRD42020172528). EVIDENCE SYNTHESIS: A total of 25 imaging features were identified in 29 studies. The most characteristic radiographic features of COVID-19 pneumonia include peripheral distribution (92.4%, 95% CI: 86.8-95.8), bilateral involvement (82.8%, 95% CI: 76.0-87.9), and ground-glass opacities (GGO) (76.0%, 95% CI: 59.5-87.3). Right lower lobe (RLL) was the most frequently involved lobe (89.0%, 95% CI: 79.6-94.4), followed by left lower lobe (LLL) in 86.5% (95% CI: 74.8-93.2) of patients. The atypical imaging features included bronchial wall thickening, lymphadenopathy, and pleural effusion, which were observed more commonly in severe and critical COVID-19 pneumonia compared to mild and moderate condition. CONCLUSIONS: Chest imaging can help to diagnose COVID-19 pneumonia, especially in regions where the availability of RT -PCR testing kits is limited. Recognition of key radiographic features of COVID-19 pneumonia is essential to identify patients at early stages, monitor disease progression, and optimize their management plan.