@article {Blazhenets910, author = {Ganna Blazhenets and Nils Schroeter and Tobias Bormann and Johannes Thurow and Dirk Wagner and Lars Frings and Cornelius Weiller and Philipp T. Meyer and Andrea Dressing and Jonas A. Hosp}, title = {Slow but Evident Recovery from Neocortical Dysfunction and Cognitive Impairment in a Series of Chronic COVID-19 Patients}, volume = {62}, number = {7}, pages = {910--915}, year = {2021}, doi = {10.2967/jnumed.121.262128}, publisher = {Society of Nuclear Medicine}, abstract = {Cognitive impairment is a frequent complaint in coronavirus disease 2019 (COVID-19) and can be related to cortical hypometabolism on 18F-FDG PET at the subacute stage. However, it is unclear if these changes are reversible. Methods: We prospectively assessed the Montreal Cognitive Assessment scores and 18F-FDG PET scans of 8 COVID-19 patients at the subacute stage (once no longer infectious) and the chronic stage (\~{}6 mo after symptom onset). The expression of the previously established COVID-19{\textendash}related covariance pattern was analyzed at both stages to examine the time course of post{\textendash}COVID-19 cognitive impairment. For further validation, we also conducted a conventional group analysis. Results: Follow-up 18F-FDG PET revealed that there was a significant reduction in the initial frontoparietal and, to a lesser extent, temporal hypometabolism and that this reduction was accompanied by a significant improvement in cognition. The expression of the previously established COVID-19{\textendash}related pattern was significantly lower at follow-up and correlated inversely with Montreal Cognitive Assessment performance. However, both 18F-FDG PET and cognitive assessment suggest a residual impairment. Conclusion: Although a significant recovery of regional neuronal function and cognition can be clearly stated, residuals are still measurable in some patients 6 mo after manifestation of COVID-19. Given the current pandemic situation and tremendous uncertainty concerning the long-term effects of COVID-19, the present study provides novel insights of the highest medical and socioeconomic relevance.}, issn = {0161-5505}, URL = {https://jnm.snmjournals.org/content/62/7/910}, eprint = {https://jnm.snmjournals.org/content/62/7/910.full.pdf}, journal = {Journal of Nuclear Medicine} }