Smell disorders in ENT clinic.

Olfactory disorders may have several causes. Nasal polyposis or chronic sinusitis can result in nasal obstructions that block the access of odorants to the olfactory epithelium, and this can explain the development of olfactory disorders. On the other hand, when nasal endoscopy has revealed that the nasal cleft is free of inflammatory or tumoural disease, olfactory disorders may be explained by neuroepithelial or central nervous system disturbances. This paper will provide information about current approaches to smell disorders in otorhinolaryngology. Major causes will be reviewed as outcomes after medical or surgical treatment. An algorithm will also be given to standardise clinical investigations, including psychophysical olfactory testing, imaging and electrophysiological examinations.