Abstract
BACKGROUND AND PURPOSE: Anosmia or hyposmia, often accompanied by changes in taste, is recognized as a common symptom that can assist in the diagnosis of coronavirus disease 2019 (COVID-19). The pathogenesis of olfactory dysfunction in COVID-19 is not yet fully understood. MR imaging represents a useful anatomic imaging method for the evaluation of olfactory dysfunction associated with varying etiologies, including viral infection, trauma, and neurodegenerative processes. This case-control study was conducted to compare quantitative measurements of olfactory anatomic structures between patients diagnosed with COVID-19 associated with persistent olfactory dysfunction and healthy controls.
MATERIALS AND METHODS: This study has a retrospective design. Cranial MR imaging was performed on all participants in both the patient and control groups. The bilateral olfactory bulb volume, olfactory tract length, and olfactory sulcus depth were measured in all patients.
RESULTS: A total of 116 people aged 18–60 years, including 36 patients diagnosed with COVID-19 and 80 controls, were included in the study. All measured values were compared between the patient and control groups. The right, left, and total olfactory bulb volume values were significantly lower in the patient group than in the control group. The patient group also had significantly lower right and left olfactory sulcus depth and olfactory tract length values compared with those in the control group.
CONCLUSIONS: MR imaging findings can be used to demonstrate olfactory injury in patients with COVID-19. The olfactory pathway may represent an alternative route for virus entry into the central nervous system.
ABBREVIATIONS:
- COVID-19
- coronavirus disease 2019
- CoV
- human coronavirus
- OB
- olfactory bulb
- OBV
- olfactory bulb volume
- OD
- olfactory dysfunction
- OSD
- olfactory sulcus depth
- OT
- olfactory tract
- OTL
- olfactory tract length
- SARS
- Severe Acute Respiratory Syndrome
Footnotes
The institution from which the work originated: Adiyaman University Faculty of Medicine, Yunus Emre Mahallesi 1164 Sokak No:13 02200 Merkez/Adıyaman/Turkey.
Disclosures: Sukru Mehmet Erturk—UNRELATED: Payment for Lectures Including Service on Speakers Bureaus: Bayer AG, Siemens.* *Money paid to the institution.
The following are the authors’ contributions: data collection: A.H.B, E.A; study design: A.H.B, E.A, E.Ay; manuscript writing: E.A; statistical analysis: S.S; figures and illustration: A.H.B; review and final editing: A.H.B, E.A, S.M.E. All authors contributed to the elaboration, critical revision, and review of intellectual content. All authors read and approved the final manuscript.
- © 2021 by American Journal of Neuroradiology
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