Correlation of olfactory function with changes in the volume of the human olfactory bulb.
ABSTRACT To investigate changes of olfactory bulb (OB) volume over time in relation to olfactory function.
Prospective, before-after trial.
Outpatient clinic of a university clinic for otorhinolaryngology.
A total of 20 patients with olfactory loss participated in the study. The duration of olfactory deficits ranged from 3 months to 6 years.
Olfactory function was assessed for phenyl ethyl alcohol odor threshold, odor discrimination, and odor identification. Olfactory bulb volume was determined using magnetic resonance imaging.
In initially hyposmic patients (n = 13), changes in OB volume were found to correlate with odor threshold changes (r = 0.82; P = .001); no such correlation was found for odor discrimination or odor identification.
As demonstrated in a longitudinal study for the first time to our knowledge, the human OB is a highly plastic structure that responds to individual changes in olfactory status.
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ABSTRACT: Disturbances of olfaction are a common occurrence in many neurological and neurosurgical patients and their correct diagnosis might be helpful in management and enhancement of quality of life. However, olfaction is seldom checked in most neurosurgical units and the "smell bottles" are often either absent or out of date. This chapter reviews systematically recent advances in our understanding of the anatomy, physiology (olfactory coding) and measurement of olfactory function in the human. The causes and symptoms of smell disorders, risk of damage to the olfactory system by various surgical procedures and, finally, the natural history of recovery and treatment of smell disorders, for example after trauma, are discussed.Advances and technical standards in neurosurgery 02/2005; 30:69-105.
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