Systematic review and meta-analysis of brain neuroimaging abnormalities in COVID-19 patients and survivors

Abstract

Background: Accumulating evidence indicates that COVID-19 may cause neurological complications detectable on brain imaging. Yet, the overall prevalence, modality-specific characteristics, and clinical implications of these neuroimaging abnormalities have not been systematically summarized through comprehensive quantitative synthesis.

Methods: We searched the PubMed, Web of Science, Scopus, Embase, Cochrane Library, and China National Knowledge Infrastructure (CNKI) databases, and Wanfang for original articles published up to August 5, 2025. The pooled proportions of brain-imaging findings on computed tomography (CT), magnetic resonance imaging (MRI), and electroencephalography (EEG), including hemorrhage, microbleeds, ischemia, stroke, encephalitis, background activity abnormality, periodic or rhythmic activity, and epileptiform discharge, were estimated using a random-effects model. This study was conducted according to PRISMA guidelines.

Results: Eighty-three eligible studies that included 9466 COVID-19 patients were included in the meta-analysis. Pooled results from 27 studies, including 3081 patients, showed that more than two-fifths (42.60%) of patients who underwent CT/MRI had objective brain abnormalities. The most frequently reported abnormalities on CT/MRI were changes in white matter and non-specific stroke. Twenty-five EEG studies, including 1273 patients, reported epileptiform discharges in one-fifth (20.54%) of cases. The systematic review of long-term brain imaging manifestations in COVID-19 survivors also found common changes in brain microstructure and function.

Conclusion: While these findings offer insights into the potential pathological mechanisms of neuroimaging abnormalities in COVID-19 patients, the high heterogeneity and variability across studies highlight the need for cautious interpretation. It will be necessary to conduct large-scale longitudinal studies with extended follow-up periods in order to validate these neuroimaging findings and clarify the long-term neuropsychiatric consequences of COVID-19.

Keywords

COVID-19 / SARS-CoV-2 / CT / MRI / EEG / brain / imaging

Supplementary data

Supplementary data are available at Psychoradiology Journal online.

Author contributions

Peng Li (Conceptualization, Data curation, Formal Analysis, Investigation, Methodology, Resources, Writing - original draft, Writing - review & editing), Shuyu Ni (Conceptualization, Data curation, Formal Analysis, Investigation, Methodology, Writing - original draft, Writing - review & editing), Xiao Lin (Conceptualization, Data curation, Formal Analysis, Investigation, Methodology, Writing - original draft, Writing - review & editing), Zengbo Ding (Writing - review & editing), Na Zeng (Formal Analysis, Software, Visualization), Yimiao Zhao (Data analysis conduction, Visualization), Mei Huan (Investigation, Software), Xuan Chen (Formal Analysis), Nan Gao (Formal Analysis, Investigation, Software), Hanliang Wei (Formal Analysis, Investigation, Software), Tong Li (Formal Analysis, Investigation, Software), Yingbo Yang (Investigation, Visualization), Beiyi Yang (Visualization), Ye Tian (Formal Analysis, Investigation, Software), Norimichi Hara (Formal Analysis, Software), Jinyuan Zhang (Formal Analysis, Software), Tao Wang (Formal Analysis, Software), Wei Yan (Writing - review & editing), Junliang Yuan (Writing - review & editing), Ying Han (Writing - review & editing), Kai Yuan (Writing - review & editing), Le Shi (Writing - review & editing), Jie Shi (Conceptualization, Project administration, Supervision, Writing - review & editing), Lin Lu (Conceptualization, Project administration, Resources, Supervision, Writing - review & editing), and Yanping Bao (Conceptualization, Project administration, Resources, Supervision, Writing - review & editing)

Conflict of interest

Lin Lu holds the position of Editor-in-Chief for Psychoradiology and is blinded from reviewing or making decisions for the manuscript.

Acknowledgements

This study was supported by the National Natural Science Foundation of China (82271543 to Peng Li, 82171514 to Yanping Bao), National Programs for Brain Science and Brain-like Intelligence Technology of China (2021ZD0200800 to Lin Lu, 2021ZD0200700 to Yanping Bao), National Key Research and Development Program of China (2021YFC0863700 to Lin Lu, 2019YFA0706200 to Peng Li), Beijing Municipal Natural Science Foundation (7212141 to Peng Li), and Capital’s Funds for Health Improvement and Research (2020–4-4115 to Peng Li).

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