Abstract:

The prevalence of low olfactory function is approximately 20%, with around 5% having anosmia. Existing therapies and outcomes are limited. More recent approaches may offer new options such as electrical stimulation at different levels of the olfactory system that could lead to an olfactory implant, or transplantation of cells from the olfactory mucosa. These approaches exploit the neuronal plasticity which plays a central role for the olfactory system. In addition, the therapeutic effect of "olfactory training" (repeated and regular exposure to odors for weeks/months) is based on this plasticity. It has been shown that OT is associated with an improvement of olfactory function, changes at the level of the olfactory mucosa, an increase of the volume of olfactory bulb and also the cortical thickness of different brain structures like frontal gyrus and entorhinal cortex. In summary, plasticity of the olfactory system is of high significance to a range of new and emerging treatments of olfactory dysfunction.