OBJECTIVES: Smell impairment (SI) is a well-known symptom of chronic rhinosinusitis with nasal polyps (CRSwNP). The aim of study was to analyze olfactory and trigeminal event-related potentials (OERPs/TERPs) and psychophysical smell tests in subjects with CRSwNP, and its potential role in clinical practice. METHODS: Prospective study included 57 subjects. Two investigated groups with CRSwNP and one control group. Group I (n = 20) contained subjects without CRSwNP before septoplasty. Group II (n = 18) contained subjects with CRSwNP without therapy. Group III (n = 19) contained subjects with CRSwNP after intranasal corticosteroid therapy. Sniffin stick identification smell test and OERPs/TERPs were performed in all subjects. RESULTS: According to the psychophysical smell test, SI was detected in 65% of subjects with CRSwNP. In the control Group I (without CRSwNP), the absence of OERPs was 5.0%, whilethe mean absence rate in Groups II, III (with CRSwNP) was 8.1%. The highest percentage of absence of OERPs was registered in Group II (11.1%). Absence of TERPs was detected in an average of 21.6% of CRSwNP subjects. Group III showed the highest percentage of absence of TERPs (32%). In the control Group I, TERPs were absent in 0% of subjects. CONCLUSION: CRSwNP significantly impairs olfactory function compared to patients without CRSwNP, Absence of TERPs was detected in an average of 21.6% of CRSwNP subjects versus healthy controls (0%). Presence of TERPs appears to be a predictor of preservation of olfactory function.

• Keywords
• Chronic rhinosinusitis, OERPs, Olfactory dysfunction, Smell test, Sniffin stick test, TERPs,
• MeSH
• Chronic Disease MeSH
• Smell * physiology   MeSH
• Adult MeSH
• Evoked Potentials * physiology   MeSH
• Middle Aged MeSH
• Humans MeSH
• Trigeminal Nerve * physiopathology   MeSH
• Nasal Polyps * physiopathology   complications   MeSH
• Olfaction Disorders * physiopathology   MeSH
• Prospective Studies MeSH
• Rhinosinusitis MeSH
• Rhinitis * physiopathology   complications   MeSH
• Sinusitis * physiopathology   complications   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article 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

OBJECTIVES: Olfactory dysfunction (OD) is a common symptom associated with Covid-19. During the Covid-19 pandemic, the importance of psychophysical olfactory tests and electrophysiological olfactory assessment increased. The purpose of the study was to analyze the psychophysical olfactory tests and the post-covid curves of olfactory event-related potentials (OERPs) and trigeminal event-related potentials (TERPs). METHODS: The prospective study included 98 subjects (62 females / 36 males). The average age was 42 years (range 21-84 years). Group I (n = 77) contained participants who had been infected with Covid-19. They were enrolled in the study at least 1 year after Covid-19. Group II (n = 21) was the healthy normosmic control group. RESULTS: In Group I, the OERPs of 18% participants were absent. Patients in Group I were statistically more likely to have an absence of OERPs (p = 0.036) than subjects in Group II. We did not detect a statistical difference in amplitudes and latencies of the OERPs between Group I and Group II. In Group I, N1 latency of the TERPs was significantly longer (p = 0.002) than in Group II. The amplitude of the N1-P2 interval of the TERPs was significantly lower (p = 0.025) in Group I than in Group II. According to the psychophysical Sniffin stick identification test, hyposmia was detected in 39% in Group I versus 0% in the control Group II. CONCLUSION: OD is a common post-covid symptom. The presence of OERPs is a significant prognostic factor for olfactory function after Covid 19. We detected a lower percentage of absence of OERPs after Covid-19 compared to the previously published studies of post-viral OD and post-infectious OD. For TERPs, we detected a longer N1 latency and a lower amplitude for the N1-P2 interval after Covid-19. OERPs and TERPs can be considered valid biomarkers to evaluate the progress of post-covid OD.

• Keywords
• Chemosensory functions, Covid-19, OERPs, Olfactory dysfunction, Post-covid, Smell, TERPs,
• MeSH
• Smell physiology   MeSH
• COVID-19 * physiopathology   MeSH
• Adult MeSH
• Evoked Potentials * physiology   MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Trigeminal Nerve physiopathology   virology   MeSH
• Olfaction Disorders * physiopathology   virology   etiology   diagnosis   MeSH
• Prospective Studies MeSH
• SARS-CoV-2 * MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article 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