Chest Imaging Findings in COVID-19 Patients: A Systematic Review and Meta-Analysis

Abstract

Background: Coronavirus disease 2019 (COVID-19) is first and foremost a respiratory illness that greatly impacts the lungs. Chest imaging, especially computed tomography (CT), has been of great help to the medical professionals to identify the virus's physical manifestations in the lungs, determine the extent of the disease, and track the changes over time. With so much research already published, a thorough summary of the imaging results would help to clarify the radiologic features of COVID-19.

Objective: This systematic review and meta-analysis aimed to summarize chest imaging findings in patients with COVID-19 and evaluate the prevalence, distribution, and temporal evolution of characteristic radiologic features.

Methods: A comprehensive search for systematic reviews, meta-analyses, and extensive reviews that have been published was done in order to find studies documenting chest imaging findings in patients with confirmed COVID-19. Studies that evaluated the features of CT and chest radiography and that were considered eligible were included. Information was taken from the studies regarding their characteristics, imaging modalities, and radiological findings reported. Both a qualitative and quantitative review were carried out to establish the pooled prevalence of the principal imaging features and to describe the temporal imaging patterns.

Results: Seven main review, based studies were taken into account, which collectively represented several thousand patients. Ground, glass opacities were by far the most common CT finding (68%) followed by bilateral lung involvement (73%), peripheral distribution (65%), and multilobar disease (59%). Consolidation (32%) and mixed ground, glass with consolidation (41%) were mostly seen in the cases of progression. Other less typical findings were vascular enlargement (27%), crazy-paving pattern (21%), pleural effusion (6%), and lymphadenopathy (5%). Imaging progression revealed a change from early focal ground- glass opacities to peak consolidation and thereafter resolution with some patients having residual fibrotic changes. Chest CT demonstrated a very high sensitivity of pulmonary involvement detection, thus indicating its role as a complementary diagnostic and monitoring tool.

Conclusion:  Chest CT scans demonstrate typical and evolving imaging features of COVID- 19, where bilateral peripheral ground-glass opacities are the most common and consistent pattern. Imaging gives useful information for diagnosis, disease staging, and follow-up, but the results should always be interpreted with clinical and laboratory data. More studies with standardized protocols and long-term follow-up are necessary to elucidate changing imaging features and post-infection lung outcomes.