Olfactory Evoked Potentials
While many clinical tests require patients cooperation in the assessment of olfactory function, performing olfactory evoked potentials rely less on the patients cooperation. To record the olfactory evoked potentials, odors are applied intranasally to patients by a special instrument called olfactometer. A computer software controls the odor simulation presented to the patient and recording of the stimulus-linked EEG.
To diagnose the olfactory dysfunction response in a patient, electric potentials of the olfactory epithelium (electro-olfactograms) that occur in response to olfactory stimulation is collected by an electrode placed in the olfactory cleft or EEG derived signals are recorded due to the activation of cortical neurons that generate electro magnetic fields.
One of the greatest advantages of implementing the olfactory evoked potential olfactometry in diagnosing patients with olfactory dysfunction, it allows the physician to diagnose the patients who have difficulties responding properly during the examination (as with children, demented, aphasic, unconscious, or inexperienced patients).