Dysfunction of Olfaction After COVID-19 Infection: Morphological and Histomolecular Investigation

Who May Qualify: - Olfactory Dysfunction group: Presence of evident OD (Parosmia, Threshold-Discrimination-Identification (TDI)-score ≤24, Subjective abnormal quantitative olfactory function; measured by a visual analogue score (VAS) of smell impairment ≥5/10 - Control group: No OD (TDI-score \>30.5.) Who Should NOT Join This Trial: - Presence of concomitant nasal mucosal pathology that might affect olfactory function or bias the study investigations - Use of anticoagulation therapy - Allergy to local anesthetics Always talk to your doctor about whether this trial is right for you.