Brain 18 F-FDG PET imaging in outpatients with post-COVID-19 conditions: findings and associations with clinical characteristics

• Published in: European journal of nuclear medicine and molecular imaging Vol. 50; no. 4; p. 1084
• Main Authors: Goehringer, François, Bruyere, Alexandra, Doyen, Matthieu, Bevilacqua, Sibylle, Charmillon, Alexandre, Heyer, Sebastien, Verger, Antoine
• Format: Journal Article
• Language: English
• Published: Germany 01-03-2023
• Subjects: Asthenia - metabolism; Brain - diagnostic imaging; Brain - metabolism; COVID-19 - diagnostic imaging; Fluorodeoxyglucose F18 - metabolism; Humans; Outpatients; Positron-Emission Tomography - methods; Retrospective Studies; COVID-19; Post-COVID-19 conditions; Outpatients; Brain involvement; Long COVID; FDG PET; Non-hospitalized; PET
• ISSN: 1619-7089

Brain
F-FDG PET imaging has the potential to provide an objective assessment of brain involvement in post-COVID-19 conditions but previous studies of heterogeneous patient series yield inconsistent results. The current study aimed to investigate brain
F-FDG PET findings in a homogeneous series of outpatients with post-COVID-19 conditions and to identify associations with clinical patient characteristics.
We retrospectively included 28 consecutive outpatients who presented with post-COVID-19 conditions between September 2020 and May 2022 and who satisfied the WHO definition, and had a brain
F-FDG PET for suspected brain involvement but had not been hospitalized for COVID-19. A voxel-based group comparison with 28 age- and sex-matched healthy controls was performed (p-voxel at 0.005 uncorrected, p-cluster at 0.05 FWE corrected) and identified clusters were correlated with clinical characteristics.
Outpatients with post-COVID-19 conditions exhibited diffuse hypometabolism predominantly involving right frontal and temporal lobes including the orbito-frontal cortex and internal temporal areas. Metabolism in these clusters was inversely correlated with the number of symptoms during the initial infection (r =  - 0.44, p = 0.02) and with the duration of symptoms (r =  - 0.39, p = 0.04). Asthenia and cardiovascular, digestive, and neurological disorders during the acute phase and asthenia and language disorders during the chronic phase (p ≤ 0.04) were associated with these hypometabolic clusters.
Outpatients with post-COVID-19 conditions exhibited extensive hypometabolic right fronto-temporal clusters. Patients with more numerous symptoms during the initial phase and with a longer duration of symptoms were at higher risk of persistent brain involvement.