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Evaluation of anterior olfactory nucleus changes on magnetic resonance imaging: could it be a game changer in smell disorders?

Published online by Cambridge University Press:  16 October 2025

Deniz Esin Tekcan Sanli Open the ORCID record for Deniz Esin Tekcan Sanli [Opens in a new window] ,
Duzgun Yildirim ,
Ismail Mese ,
Eren Yilmaz ,
Ozlem Saatci ,
Ahmet Necati Sanli  and
Aytug Altundag
Deniz Esin Tekcan Sanli*
Affiliation:
Department of Radiology, School of Medicine, Gaziantep University, Turkey
Duzgun Yildirim
Affiliation:
Department of Radiology, School of Medicine, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
Ismail Mese
Affiliation:
Department of Radiology, Uskudar State Hospital, Istanbul, Turkey
Eren Yilmaz
Affiliation:
Department of Ear, Nose, Throat, Acibadem Taksim Hospital, Istanbul, Turkey
Ozlem Saatci
Affiliation:
Department of Ear, Nose, Throat, Sancaktepe Education and Research Hospital, Istanbul, Turkey
Ahmet Necati Sanli
Affiliation:
Department of General Surgery, ADN International Hospital, Gaziantep, Turkey
Aytug Altundag
Affiliation:
Prof. Dr. Aytug Altundag Clinic, Istanbul, Turkey
*
Corresponding author: Deniz Esin Tekcan Sanli; Email: tekcandenizesin@gmail.com
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Abstract

Objectives

This study aimed to investigate morphological and signal changes of the anterior olfactory nucleus (AON) on high-resolution magnetic resonance imaging (MRI) in patients with olfactory dysfunction (OD) of varying aetiologies.

Methods

A retrospective analysis of 135 patients with post–coronavirus disease 2019 (COVID-19), post-viral, or post-traumatic OD was conducted. High-resolution MRI was used to assess AON signal intensity and area, as well as olfactory bulb (OB) morphology. Clinical evaluation included Threshold (T), Discrimination (D), and Identification (I) scores and the presence of parosmia.

Results

AON signal abnormalities were present in 55.5 % of cases. Post–COVID-19 patients had significantly lower TDI scores than other groups. While AON signal and morphological differences were observed across aetiologies, a consistent correlation with TDI scores was not found, except in limited subgroup analyses.

Conclusion

Abnormalities of the AON are common in OD, but do not reliably indicate severity or aetiology. Further research is needed to determine their clinical relevance.

Keywords

anosmiamagnetic resonance ımagingolfactory bulbolfactory pathwayssmell disorders

Information

Type
Main Article
Information
The Journal of Laryngology & Otology , Volume 140 , Issue 1 , January 2026 , pp. 52 - 59
Copyright
© The Author(s), 2025. Published by Cambridge University Press on behalf of J.L.O. (1984) LIMITED.

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Footnotes

Deniz Esin Tekcan Sanli takes responsibility for the integrity of the content of the paper

References

Boesveldt, S, Parma, V. The importance of the olfactory system in human well-being, through nutrition and social behavior. Cell Tissue Res 2021;383:559–67CrossRefGoogle Scholar
Croy, I, Symmank, A, Schellong, J, Hummel, C, Gerber, J, Joraschky, P, et al. Olfaction as a marker for depression in humans. J Affect Disord 2014;160:80–6CrossRefGoogle ScholarPubMed
Dalal, T, Gupta, N, Haddad, R. Bilateral and unilateral odor processing and odor perception. Commun Biol 2020;3:150CrossRefGoogle ScholarPubMed
Yunpeng, Z, Han, P, Joshi, A, Hummel, T. Individual variability of olfactory fMRI in normosmia and olfactory dysfunction. Eur Arch Otorhinolaryngol 2021;278:379–87CrossRefGoogle ScholarPubMed
Esposito, F, Cirillo, M, De, Micco R, Caiazzo, G, Siciliano, M, Russo, AG, et al. Olfactory loss and brain connectivity after COVID-19. Hum Brain Mapp 2022;43:1548–60CrossRefGoogle ScholarPubMed
Yildirim, D, Altundag, A, Tekcan, Sanli DE, Bakir, A, Eryurekli, A, Alis, D, et al. New perspective on imaging of olfactory dysfunction: does size matter? Eur J Radiol 2020;132:109290CrossRefGoogle ScholarPubMed
Kondoh, T, Yamada, S, Shioda, S, Torii, K. Central olfactory pathway in response to olfactory stimulation in rats detected by magnetic resonance imaging. Chem Senses 2005;30:172–3CrossRefGoogle ScholarPubMed
Muir, ER, Biju, KC, Cong, L, Rogers, WE, Torres, Hernandez E, Duong, TQ, et al. Functional MRI of the mouse olfactory system. Neurosci Lett 2019;704:57–61CrossRefGoogle ScholarPubMed
Brunert, D, Medinaceli Quintela, R, Rothermel, M. The anterior olfactory nucleus revisited - an emerging role for neuropathological conditions? Prog Neurobiol 2023;228:102486CrossRefGoogle ScholarPubMed
Son, G, Steinbusch, HWM, López-Iglesias, C, Moon, C, Jahanshahi, A. Severe histomorphological alterations in post-mortem olfactory glomeruli in Alzheimer’s disease. Brain Pathol 2022;32:e13033CrossRefGoogle ScholarPubMed
Gardner, B, Dieriks, BV, Cameron, S, Mendis, LHS, Turner, C, Faull, RLM, et al. Metal concentrations and distributions in the human olfactory bulb in Parkinson’s disease. Sci Rep 2017;7:10454CrossRefGoogle ScholarPubMed
Altundag, A, Saatci, O, Sanli, DET, Duz, OA, Sanli, AN, Olmuscelik, O, et al. The temporal course of COVID-19 anosmia and relation to other clinical symptoms. Eur Arch Otorhinolaryngol 2021;278:1891–7CrossRefGoogle ScholarPubMed
Liu, ZY, Vaira, LA, Boscolo-Rizzo, P, Walker, A, Hopkins, C. Post-viral olfactory loss and parosmia. BMJ Med 2023;2:e000382CrossRefGoogle ScholarPubMed
Gunder, N, Hummel, T. Parosmia in patients with post-infectious olfactory dysfunction in the era of COVID-19-associated olfactory impairment. HNO 2024;72:649–56CrossRefGoogle ScholarPubMed
Lee, DY, Lee, WH, Wee, JH, Kim, J-W. Prognosis of postviral olfactory loss: follow-up study for longer than one year. Am J Rhinol Allergy 2014;28:419–22CrossRefGoogle ScholarPubMed
Pellegrino, R, Farruggia, MC, Small, DM, Veldhuizen, MG. Post-traumatic olfactory loss and brain response beyond olfactory cortex. Sci Rep 2021;11:4043CrossRefGoogle ScholarPubMed
Yildirim, D, Kandemirli, SG, Tekcan Sanli, DE, Akinci, O, Altundag, A. A comparative olfactory MRI, DTI and fMRI study of COVID-19 related anosmia and post viral olfactory dysfunction. Acad Radiol 2022;29:31–41CrossRefGoogle ScholarPubMed
Menzel, S, Haehner, A, Woosch, D, Marquardt, B, Ressel, C, Draf, J, et al. Parosmia as a predictor of a better olfactory function in COVID- 19: a multicentric longitudinal study for upper respiratory tract infections. Eur Arch Otorhinolaryngol 2023;280:2331–40CrossRefGoogle ScholarPubMed
Howell, J, Costanzo, RM, Reiter, ER. Head trauma and olfactory function. World J Otorhinolaryngol Head Neck Surg 2018;4:39–45CrossRefGoogle ScholarPubMed
Collet, S, Grulois, V, Bertrand, B, Rombaux, P. Post-traumatic olfactory dysfunction: a cohort study and update. B-ENT 2009;5:97–107Google ScholarPubMed
Cavazzana, A, Larsson, M, Münch, M, Hähner, A, Hummel, T. Postinfectious olfactory loss: a retrospective study on 791 patients. Laryngoscope 2018;128:10–15CrossRefGoogle Scholar
Rombaux, P, Huart, C, Deggouj, N, Duprez, T, Hummel, T. Prognostic value of olfactory bulb volume measurement for recovery in postinfectious and posttraumatic olfactory loss. Otolaryngol Head Neck Surg 2012;147:1136–41CrossRefGoogle ScholarPubMed
Tervo, JP, Jacobson, PT, Vilarello, BJ, Saak, TM, Caruana, FF, Gallagher, LW, et al. Recovery rates of persistent post-COVID-19 olfactory dysfunction using psychophysical assessment: a longitudinal cohort study. World J Otorhinolaryngol Head Neck Surg 2024;10:79–87CrossRefGoogle ScholarPubMed