{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T12:26:59Z","timestamp":1789043219756,"version":"build-2803163510"},"reference-count":44,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T00:00:00Z","timestamp":1766016000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Ministry of Health","award":["01K\/20343"],"award-info":[{"award-number":["01K\/20343"]}]},{"name":"Open Access Publication Fund of the University of Bonn"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Background\/Objectives: SARS-CoV-2 infection has been linked to long-term neurological sequelae and structural brain alterations. Previous analyses, including baseline results from the COVIMMUNE-Clin study, showed brain volume reductions in COVID-19 patients. Longitudinal data on progression are scarce. This study examined brain volume changes 12 months after baseline MRI in individuals who have recovered from mild or severe COVID-19 compared with controls. Methods: In this IRB-approved cohort study, 112 out of 172 recruited age- and sex-matched participants (38 controls, 36 mild\/asymptomatic 38 severe COVID-19) underwent standardized brain MRI 12 months after baseline. Volumetric analysis was performed using AI-based software (mdbrain). Regional volumes were compared between groups with respect to absolute and normalized values. Multivariate regression controlled for demographics. Results: After 12 months, a significant decline in right hippocampal volume was observed across all groups, most pronounced in severe COVID-19 (SEV: \u0394 = \u22120.32 mL, p = 0.001). Normalized to intracranial volume, the reduction remained significant (SEV: \u0394 = \u22120.0003, p = 0.001; ASY: \u0394 = \u22120.0001, p = 0.001; CTL: minimal reduction, \u0394 \u2248 0, p = 0.005). Minor reductions in frontal and parietal lobes (e.g., right frontal SEV: \u0394 = \u22121.35 mL, p = 0.001), largely fell within physiological norms. These mild regional changes are consistent with expected ageing-related variability and do not suggest pathological progression. No widespread progressive atrophy was detected. Conclusions: This study demonstrates delayed, severity-dependent right hippocampal atrophy in recovered COVID-19 patients, suggesting long-term vulnerability of this memory-related region. In contrast, no progression of atrophy in other areas was observed. These findings highlight the need for extended post-COVID neurological monitoring, particularly of hippocampal integrity and its cognitive relevance.<\/jats:p>","DOI":"10.3390\/diagnostics15243244","type":"journal-article","created":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T13:45:07Z","timestamp":1766065507000},"page":"3244","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Longitudinal Monitoring of Brain Volume Changes After COVID-19 Infection Using Artificial Intelligence-Based MRI Volumetry"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-7587-382X","authenticated-orcid":false,"given":"Zeynep","family":"Bendella","sequence":"first","affiliation":[{"name":"Department of Neuroradiology, Faculty of Medicine, University Hospital Bonn, Rheinische Friedrich-Wilhelm-Universit\u00e4t Bonn, 53127 Bonn, Germany"},{"name":"German Centre for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8889-8385","authenticated-orcid":false,"given":"Catherine Nichols","family":"Widmann","sequence":"additional","affiliation":[{"name":"German Centre for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany"},{"name":"Department of Neurodegenerative Diseases and Geriatric Psychiatry, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universit\u00e4t Bonn, Venusberg-Campus 1, 53127 Bonn, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6711-3347","authenticated-orcid":false,"given":"Christine","family":"Kindler","sequence":"additional","affiliation":[{"name":"Department of Parkinson, Sleep and Movement Disorders, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universit\u00e4t Bonn, Venusberg-Campus 1, 53127 Bonn, Germany"},{"name":"Department of Vascular Neurology, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universit\u00e4t Bonn, Venusberg-Campus 1, 53127 Bonn, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6029-4192","authenticated-orcid":false,"given":"Robert","family":"Haase","sequence":"additional","affiliation":[{"name":"Department of Neuroradiology, Faculty of Medicine, University Hospital Bonn, Rheinische Friedrich-Wilhelm-Universit\u00e4t Bonn, 53127 Bonn, Germany"},{"name":"German Centre for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Malte","family":"Sauer","sequence":"additional","affiliation":[{"name":"Department of Neuroradiology, Faculty of Medicine, University Hospital Bonn, Rheinische Friedrich-Wilhelm-Universit\u00e4t Bonn, 53127 Bonn, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael T.","family":"Heneka","sequence":"additional","affiliation":[{"name":"German Centre for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany"},{"name":"Department of Neurodegenerative Diseases and Geriatric Psychiatry, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universit\u00e4t Bonn, Venusberg-Campus 1, 53127 Bonn, Germany"},{"name":"Luxembourg Centre for Systems Biomedicine, L-4365 Esch-sur-Alzette, Luxembourg"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexander","family":"Radbruch","sequence":"additional","affiliation":[{"name":"Department of Neuroradiology, Faculty of Medicine, University Hospital Bonn, Rheinische Friedrich-Wilhelm-Universit\u00e4t Bonn, 53127 Bonn, Germany"},{"name":"German Centre for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0985-1517","authenticated-orcid":false,"given":"Frederic Carsten","family":"Schmeel","sequence":"additional","affiliation":[{"name":"Department of Neuroradiology, Faculty of Medicine, University Hospital Bonn, Rheinische Friedrich-Wilhelm-Universit\u00e4t Bonn, 53127 Bonn, Germany"},{"name":"German Centre for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Rezaei, N. 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