Association of olfactory training with olfactory bulb morphology in adults with post-viral long-lasting olfactory dysfunction: A COVID-19 related prospective study

IF 1.6 4区医学 Q2 OTORHINOLARYNGOLOGY

Auris Nasus Larynx Pub Date : 2025-02-01 DOI:10.1016/j.anl.2025.01.006

Mustafa Baran , Mahmut Tayyar Kalcioglu , Ahmet Mutlu , Basak Atalay , Mahmut Bilal Dogan , Guler Ozturk

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引用次数: 0

Abstract

Objective

In this prospective case-controlled study, we aimed to examine changes in olfactory bulb (OB) morphology due to COVID-19 infection and to examine the effects of olfactory training (OT).

Methods

This study included 29 patients with anosmia or hyposmia due to COVID-19 infection (Group 1), 24 normosmic patients after COVID-19 infection (Group 2), and 25 normosmic subjects without COVID-19 infection (Group 3). OB volumes, thickness, length, sulcus depth, and signal intensity were evaluated using magnetic resonance imaging (MRI). Psychophysical tests (odor discrimination, thresholds, and odor identification) and a survey of olfactory symptoms were performed. After 12 weeks of OT, the MRI data and odor scores of Group 1 were compared with those of the other groups.

Results

OB volumes were significantly smaller in Group 1 (54.01±2.92 mm3) compared with the other groups (group 2:56.7±3.2 mm3 and group 3:59.45±3.09 mm3). The OB thicknesses and lengths differed significantly between Group 1 and Groups 2 and 3. Group 1 had abnormalities in the OB signal intensity in the form of diffusely increased signal intensity compared with the others groups. Following OT, OB volume (right, p= 0.002; left, p=0.021) and Threshold Discrimination Identification score (p< 0.001) significantly increased in Group 1 patients.

Conclusion

These findings suggest that post-COVID olfactory loss is associated with smaller OB volumes and increased OB signal intensity. Additionally, this study provides evidence supporting the effectiveness of OT in improving olfactory function and OB volume in patients with long-lasting post-COVID-19 symptoms.

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来源期刊

Auris Nasus Larynx 医学-耳鼻喉科学

CiteScore

3.40

自引率

5.90%

发文量

169

审稿时长

30 days

期刊介绍： The international journal Auris Nasus Larynx provides the opportunity for rapid, carefully reviewed publications concerning the fundamental and clinical aspects of otorhinolaryngology and related fields. This includes otology, neurotology, bronchoesophagology, laryngology, rhinology, allergology, head and neck medicine and oncologic surgery, maxillofacial and plastic surgery, audiology, speech science. Original papers, short communications and original case reports can be submitted. Reviews on recent developments are invited regularly and Letters to the Editor commenting on papers or any aspect of Auris Nasus Larynx are welcomed. Founded in 1973 and previously published by the Society for Promotion of International Otorhinolaryngology, the journal is now the official English-language journal of the Oto-Rhino-Laryngological Society of Japan, Inc. The aim of its new international Editorial Board is to make Auris Nasus Larynx an international forum for high quality research and clinical sciences.