Examination and classification of human olfactory mucosa in patients with clinical olfactory disturbances.

To determine objectively the degree of olfactory disturbance, we biopsied the olfactory mucosa from patients who complained of anosmia. The olfactory disturbances in this study were caused by choanal atresia, chronic sinusitis, viral inflammation, and head trauma, as well as by congenital and idiopathic anosmia. The biopsy specimens were examined by light microscopy and the degree of mucosal degeneration present was classified according to five grades. The clinical courses of the patients studied paralleled the changes found in the olfactory mucosa.