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

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