- Keywords
- ANOSMIA *, ELECTROENCEPHALOGRAPHY *, OLFACTORY NERVE *, PLETHYSMOGRAPHY *, SENSORY DEPRIVATION *,
- MeSH
- Electroencephalography * MeSH
- Humans MeSH
- Olfactory Nerve * MeSH
- Olfactometry * MeSH
- Plethysmography * MeSH
- Olfaction Disorders * MeSH
- Sensory Deprivation * MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- MeSH
- Audiometry MeSH
- Smell * MeSH
- Electroencephalography MeSH
- Laryngectomy * MeSH
- Middle Aged MeSH
- Humans MeSH
- Olfactory Nerve physiopathology MeSH
- Plethysmography, Impedance MeSH
- Postoperative Complications MeSH
- Olfaction Disorders etiology MeSH
- Aged MeSH
- Auditory Threshold MeSH
- Age Factors MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Aged MeSH
- Publication type
- Journal Article MeSH
The subjective and demanding nature of olfactory testing means that it is often neglected in clinic despite loss of smell leading to significant limitations in everyday life. The list of diseases associated with loss of olfaction far exceeds the field of otorhinolaryngology and can also be seen in neurodegenerative disorders. Knowledge of possible clinical testing is essential to determine a proper differential diagnosis for the loss of olfactory sense. Causes of olfactory impairment can be divided into either failure in transferring odour to the organ of perception or damage to the olfactory pathway structure itself. Examination should therefore include methods evaluating cross-sectional area and patency of the nasal cavity as well as subjective or objective assessment of olfactory function. In this report we summarize several articles, studies, and our own experiences to provide a comprehensive review of their current clinical usage including their benefits, limitations, and possible outcomes. We also discuss the mechanism of olfaction step by step to provide a full understanding of the possible errors depending on the localization in the pathway and the methods designed for their detection. We discuss the correlation of the microbiome in nasal polyposis and chronic rhinitis with olfactory impairment using objective olfactometry. The topic of objective olfactometry and the examination of olfactory event-related potentials (OERP) is commented upon in detail.
- Keywords
- anosmia, hyposmia, objective olfactometry, odourants, olfactory event-related potentials, olfactory system, parosmia,
- Publication type
- Journal Article MeSH
- Review MeSH
INTRODUCTION: We report a case series two patients of Guillain-Barré syndrome (GBS) associated with previous COVID-19 that both patients survived. GBS is an immune-mediated disease that affects peripheral nerves and can cause life-threatening complications. CASE REPORTS: In both cases (53-year-old female and 59-year-old male) with severe GBS with complications, the smell of sense was investigated subjectively using Sniffin' sticks identification tests and objectively using objective olfactometry by the evaluation of olfactory event-related potentials (OERPs). Both patients had good results of the subjective Sniffin' sticks identification test without patholgical findings. Results of objective examination of OERPs: the P2-N1 wave complex was equipotent. No olfactory disturbance could be detected in either case, OERPs were plentiful in both cases. CONCLUSION: The presentation of a case series two patients of post-covid GBS are an example of one of the many complications of COVID-19 that can cause prolonged recovery. Despite the severe course of GBS and the long recovery time, both patients returned to normal life. An expanded prospective study is planned for the future to investigate post-covid olfactory impairment. The prevalence of GBS associated with COVID-19 is still unknown but it is evident that both mild and severe forms of GBS have been described in patients.
- Keywords
- COVID-19 infection, Guillain-Barré syndrome, Sniffin stick tests, objective olfactometry, olfactory event-related potentials,
- MeSH
- Betacoronavirus MeSH
- Smell physiology MeSH
- COVID-19 * complications physiopathology MeSH
- Evoked Potentials * physiology MeSH
- Guillain-Barre Syndrome * physiopathology diagnosis MeSH
- Coronavirus Infections complications physiopathology diagnosis MeSH
- Middle Aged MeSH
- Humans MeSH
- Pandemics MeSH
- Olfaction Disorders etiology physiopathology diagnosis MeSH
- SARS-CoV-2 * MeSH
- Pneumonia, Viral complications physiopathology diagnosis MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Case Reports MeSH
INTRODUCTION: In recent years, the evaluation of potential events related to olfactory events (OERPs) and trigeminal events (TERPs) has become increasingly important in the diagnosis of olfactory disorders. This technique is increasingly used in basic research and clinical practice to evaluate people suffering from olfactory disorders. PURPOSE OF THE STUDY: In a pilot project of the first investigations of OERPs and TERPs in the Czech Republic, we analyse the event-related potentials of the data of normosmic participants. METHODS: In the prospective study, 21 normosmic participants were enrolled for a 2-year period (5/2021-5/2023). OERPs/TERPs were recorded at the scalp vertex (electrode Pz/Cz). Odourants 2-phenylethanol/CO2 were used to selectively activate Nervus olfactorius/ Nervus trigeminus. Brain responses to olfactory/trigeminal stimuli (EEG) were recorded in 21/18 normosmic subjects. RESULTS: In the statistical analysis of the olfactory interval N1-P2 (age, gender), we found no statistically significant differences. In the statistical analysis of the trigeminal interval N1-P2 (age, gender) we found statistically significant differences in amplitude by gender (male amplitudes were higher than female amplitudes, p = 0.006). CONCLUSION: Our pilot data can function very well as an internal guide for ongoing and future olfactory research studies. Evaluation of the presence of OERPs appears to be an important parameter for the evaluation of olfactory disorders. The absence of OERPs is a strong indicator of the presence of olfactory dysfunction.
- Keywords
- Evaluation of smell, Objective olfactometry, Odourants, Olfactory event-related potentials, Trigeminal event-related potentials,
- MeSH
- Smell * physiology MeSH
- Evoked Potentials physiology MeSH
- Humans MeSH
- Pilot Projects MeSH
- Olfaction Disorders * diagnosis MeSH
- Prospective Studies MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Czech Republic MeSH
OBJECTIVE: To evaluate a brief olfactory test based on pleasantness rating of olfactory and trigeminal stimulants. DESIGN: Criterion standard. SETTING: University hospital. PARTICIPANTS: A total of 60 participants (48 healthy and 12 with olfactory loss) aged 16 to 81 years. INTERVENTIONS: The new test of odor pleasantness (TOP) based on classification of odorants and trigeminal stimulants into 4 categories was compared with 2 standard tests of subjective olfactometry. MAIN OUTCOME MEASURE: We evaluated the possible use of the TOP in assessment of olfactory and the trigeminal system in healthy individuals and those with olfactory loss. RESULTS: All 3 tests demonstrated significant mutual correlation (P < .01), and persons with olfactory loss scored lower than healthy participants (P < .01). Using exploratory factor analysis and cluster analysis, we found that healthy individuals classified odorants accurately according to the degree of their hedonic character. CONCLUSION: The TOP offers outcomes similar to those of standard tests of olfaction that are based on psychophysical testing.
- MeSH
- Olfactory Perception * MeSH
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Adolescent MeSH
- Young Adult MeSH
- Trigeminal Nerve physiology MeSH
- Odorants * MeSH
- Olfaction Disorders physiopathology MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Adolescent MeSH
- Young Adult MeSH
- Male MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
