Cerebral imaging and olfactory disorders: a review. Olfactory disorders are often misjudged and rarely given due clinical consideration. Nevertheless, they occur in a wide range of neurological disorders, and their evaluation can help in diagnosis. Whereas psychophysical tests have been used to evaluate olfactory dysfunction in numerous diseases, functional brain imaging using olfactory stimuli is an emergent technique and few studies have been published to date. After a reminder of cerebral imaging and analysis techniques and a rapid description of our actual knowledge of olfactory processes in healthy subjects, the current review focuses on cerebral imaging studies performed on patients with neurological disorders and presenting olfactory dysfunction. Neurological disorders such as Alzheimer's disease, Parkinson's disease, epilepsy, migraine, multiple chemical sensitivity and schizophrenia are examined.