Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Sep;63(9):1233-1242.
doi: 10.1177/02841851211034043. Epub 2021 Jul 20.

Peripheral and central smell regions in COVID-19 positive patients: an MRI evaluation

Veysel Burulday  1 , Merve Sefa Sayar  2 , Nuray Bayar Muluk  3
Affiliations

Peripheral and central smell regions in COVID-19 positive patients: an MRI evaluation

Veysel Burulday et al. Acta Radiol. 2022 Sep.

Abstract

Background: Coronaviruses may lead to invasion of the central nervous system.

Purpose: To investigate the effects of COVID-19 infection on smell using cranial magnetic resonance imaging (MRI).

Material and methods: Cranial MRI scans of 23 patients with COVID-19 (patient group [PG]) and 23 healthy controls (HCs) were evaluated. Peripheric (olfactory bulb [OB] volume and olfactory sulcus [OS] depth) and central (insular gyrus and corpus amygdala areas) smell regions were measured.

Results: Smell loss was present in nine patients (39.1%) in the PG. The means of the disease duration and antiviral treatment were 3.00 ± 2.35 and 5.65 ± 1.72 days, respectively. OB volumes of the PG were significantly lower than those of the HCs bilaterally. However, no significant differences were observed between the OS depth, insular gyrus, and corpus amygdala areas of both groups. The left corpus amygdala areas were both increased with the increased disease (P = 0.035, r = 0.442) and treatment durations (P = 0.037, r = 0.438). In the PG, longer treatment duration, increase in C-reactive protein (CRP), lymphocyte count decrease, and positive thoracic computed tomography (CT) involvement were related to OS depth decrease. Right corpus amygdala areas increased in patients with COVID-19 with increased D-dimer values, and thoracic CT involvement was detected.

Conclusion: COVID-19 disease affects the peripheric smell region of OBs and does not affect the central smell regions of the insular gyrus and corpus amygdala areas. The importance of our study is to detect MRI findings in patients with COVID-19 leading to odor disorders. These findings may help in diagnosing the disease at an early stage.

Keywords: COVID-19; corpus amygdala area; insular gyrus area; olfactory bulb volume; olfactory sulcus depth.

PubMed Disclaimer

Conflict of interest statement

Declaration of conflicting interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Figures

Fig. 1.
Fig. 1.
(a) On coronal T2W FSE MRI images, OB volume measurements are shown. (b) On coronal T2W FSE MRI scans, OS depth measurements are shown. (c) On axial FLAIR MRI scans, insular gyrus area measurements are shown. (d) On axial FLAIR MRI scans, corpus amygdala area measurements are shown. FLAIR, fluid-attenuated inversion recovery; FSE, fast spin echo; MRI, magnetic resonance imaging; OB, olfactory bulb; OS, olfactory sulcus; T2W, T2-weighted.
Fig. 2.
Fig. 2.
Scatter plots of correlation between OB volume R and OB volume L in patients with COVID-19. OB, olfactory bulb.
Fig. 3.
Fig. 3.
Scatter plots of correlation between corpus amygdala area R and corpus amygdala area L in patients with COVID-19.
Fig. 4.
Fig. 4.
Scatter plots of correlation between duration of the disease and corpus amygdala area L in patients with COVID-19.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Glass WG, Subbarao K, Murphy B, et al.. Mechanisms of host defense following severe acute respiratory syndrome‐coronavirus (SARS‐CoV) pulmonary infection of mice. J Immunol 2004; 173:4030–4039. - PubMed
    1. Li YC, Bai WZ, Hashikawa T.The neuroinvasive potential of SARS-CoV2 may play a role in the respiratory failure of COVID-19 patients. J Med Virol 2020; 92:552–555. - PMC - PubMed
    1. Lechien JR, Chiesa-Estomba CM, Place S, et al.. Clinical and epidemiological characteristics of 1420 European patients with mild-to-moderate coronavirus disease 2019. J Intern Med 2020;288:335–344. - PMC - PubMed
    1. Lee Y, Min P, Lee S, et al.. Prevalence and duration of acute loss of smell or taste in COVID-19 patients. J Korean Med Sci 2020; 35:e174. - PMC - PubMed
    1. Mullol J, Alobid I, Mariño-Sánchez F, et al.. The loss of smell and taste in the COVID-19 outbreak: a tale of many countries. Curr Allergy Asthma Rep 2020; 20:61. - PMC - PubMed