{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:05:01Z","timestamp":1760058301684,"version":"build-2065373602"},"reference-count":26,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,3,29]],"date-time":"2025-03-29T00:00:00Z","timestamp":1743206400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"West University of Timisoara"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Neurological symptoms such as impaired smell and taste have been recognized as hallmark manifestations of severe acute respiratory syndrome coronavirus (SARS-CoV-2) infection. This study investigates and quantifies microstructural changes in the white matter of the olfactory bulb and taste-related brain regions (frontal operculum, insular cortex and parietal operculum) using diffusion-weighted magnetic resonance imaging (DW-MRI). Apparent diffusion coefficient (ADC) values were measured in patients with confirmed coronavirus disease of 2019 (COVID-19) at the onset of anosmia and ageusia (24 patients, scanned between March and December 2020), 1 month post-infection (20 subjects) and 36 months post-infection (20 participants). ADC values were analyzed over time and compared to normal white matter ADC ranges (calculated retrospectively from 979 pre-pandemic patients) and to those from patients infected with the 2024 strain of SARS-CoV-2 (27 patients). The results revealed significantly elevated ADC values in the white matter of the targeted brain regions, with a peak at the time of infection, followed by a decline 1 month post-infection, and a return to near-normal levels 3 years later. In contrast, the 2024 COVID-19 variant demonstrated reduced virus-related alterations in brain microstructure compared to the 2020 strain. These findings highlight the potential of DWI as a non-invasive tool for elucidating the molecular mechanisms underlying olfactory and taste dysfunction in COVID-19 patients.<\/jats:p>","DOI":"10.3390\/ijms26073164","type":"journal-article","created":{"date-parts":[[2025,3,31]],"date-time":"2025-03-31T03:25:02Z","timestamp":1743391502000},"page":"3164","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Neurological Impact of SARS-CoV-2 Changing Variants: A 4-Year DW-MRI Study on Olfactory and Taste-Related Brain Regions"],"prefix":"10.3390","volume":"26","author":[{"given":"Teodora Anca","family":"Albu","sequence":"first","affiliation":[{"name":"Department of Physics, West University of Timisoara, 300223 Timisoara, Romania"},{"name":"ScanExpert, 300627 Timisoara, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nicoleta","family":"Iacob","sequence":"additional","affiliation":[{"name":"Miclaus Diagnostic Hub SRL, 307200 Ghiroda, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniela","family":"Susan-Resiga","sequence":"additional","affiliation":[{"name":"Department of Physics, West University of Timisoara, 300223 Timisoara, Romania"},{"name":"Academia Romana Filiala Timisoara, 300223 Timisoara, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"361","DOI":"10.1038\/s41579-023-00878-2","article-title":"The evolution of SARS-CoV-2","volume":"21","author":"Markov","year":"2023","journal-title":"Nat. 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