Observational studyJournal of neurology2023
MRI evidence of olfactory system alterations in patients with COVID-19 and neurological symptoms.
Observational study in Journal of neurology, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers.
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Who cites it
16 citing papers in PubMed, 19 citations in OpenAlex.
- High-field MRI correlates with immunohistochemical analysis of the normal and Alzheimer's disease anterior olfactory nucleus.NeuroImage · 2026Article
- Combination antiviral and anti-inflammatory therapy mitigates persistent neurological deficits in mice post SARS-CoV-2 infection.Proceedings of the National Academy of Sciences of the United States of America · 2026Article
- Cortical morphology alterations in non-COVID-19 post-infectious olfactory dysfunction.Scientific reports · 2025Article
- Olfactory Dysfunction and Cognitive Decline: Are They Related?Current allergy and asthma reports · 2025Review
- Post-COVID-19 condition: clinical phenotypes, pathophysiological mechanisms, pathology, and management strategies.The Journal of pathology · 2025Review
- Mapping the Olfactory Brain: A Systematic Review of Structural and Functional Magnetic Resonance Imaging Changes Following COVID-19 Smell Loss.Brain sciences · 2025Review
- Changes in olfactory bulb volume and olfactory sulcus depth in COVID-19 infection: an autopsy study.European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery · 2025Article
- Functional Connectivity Alterations Associated with COVID-19-Related Sleep Problems: A Longitudinal Resting-State fMRI Study.Nature and science of sleep · 2025Article
- MRI evidence of gray matter loss in COVID-19 patients with cognitive and olfactory disorders.Annals of clinical and translational neurology · 2024Article
- Persistent Neurological Deficits in Mouse PASC Reveal Antiviral Drug Limitations.bioRxiv : the preprint server for biology · 2024Article
- Long-term effects of SARS-CoV-2 infection in patients with and without chemosensory disorders at disease onset: a psychophysical and magnetic resonance imaging exploratory study.Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology · 2024Article
- The Growing Understanding of the Pituitary Implication in the Pathogenesis of Long COVID-19 Syndrome: A Narrative Review.Advances in respiratory medicine · 2024Review
- A Comprehensive Review of COVID-19-Related Olfactory Deficiency: Unraveling Associations with Neurocognitive Disorders and Magnetic Resonance Imaging Findings.Diagnostics (Basel, Switzerland) · 2024Review
- Long COVID-19-related and non-COVID-19 postviral olfactory dysfunction a comparative MRI study focusing on the olfactory cleft and bulbs.Frontiers in neurology · 2024Article
- Seven-tesla magnetic resonance imaging of the nervus terminalis, olfactory tracts, and olfactory bulbs in COVID-19 patients with anosmia and hypogeusia.Frontiers in radiology · 2024Article
- Olfactory Epithelium Infection by SARS-CoV-2: Possible Neuroinflammatory Consequences of COVID-19.Complex psychiatryReview
Corrections and comments
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Authors and funding
12 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
BACKGROUND AND
objectiveDespite olfactory disorders being among the most common neurological complications of coronavirus disease 2019 (COVID-19), their pathogenesis has not been fully elucidated yet. Brain MR imaging is a consolidated method for evaluating olfactory system's morphological modification, but a few quantitative studies have been published so far. The aim of the study was to provide MRI evidence of olfactory system alterations in patients with COVID-19 and neurological symptoms, including olfactory dysfunction.
methods196 COVID-19 patients (median age: 53 years, 56% females) and 39 controls (median age 55 years, 49% females) were included in this cross-sectional observational study; 78 of the patients reported olfactory loss as the only neurological symptom. MRI processing was performed by ad-hoc semi-automatic processing procedures. Olfactory bulb (OB) volume was measured on T2-weighted MRI based on manual tracing and normalized to the brain volume. Olfactory tract (OT) median signal intensity was quantified on fluid attenuated inversion recovery (FLAIR) sequences, after preliminary intensity normalization.
resultsCOVID-19 patients showed significantly lower left, right and total OB volumes than controls (p < 0.05). Age-related OB atrophy was found in the control but not in the patient population. No significant difference was found between patients with olfactory disorders and other neurological symptoms. Several outliers with abnormally high OT FLAIR signal intensity were found in the patient group.
conclusionsBrain MRI findings demonstrated OB damage in COVID-19 patients with neurological complications. Future longitudinal studies are needed to clarify the transient or permanent nature of OB atrophy in COVID-19 pathology.
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