An evoked potential (EP) or evoked response is an electrical potential recorded from the nervous system of a human or other animal following presentation of a stimulus, as distinct from spontaneous potentials as detected by electroencephalography (EEG), electromyography (EMG), or other electrophysiological recording method.
Evoked Potentials: Electrodes are applied to monitor visual, auditory and nerve pathways. These procedures are used to help assess brain and brain stem function. Patients who are sent for evoked potential testing may be experiencing clinical symptoms/problems similar to those referred for EEGs. Frequent symptoms experienced by patients having these procedures are dizziness, tinnitus, loss of balance, loss of vision, loss of sensation.
Evoked Potential monitoring during surgery: Evoked potentials may be monitored during some types of surgery, specifically during higher risk spinal surgeries for fusions or decompression, and during some craniotomies. Evoked potential monitoring during surgery gives the surgeon important information regarding sensory/motor pathways in the brain and spinal cord, and can be a valuable tool to help assure desirable outcomes/lack of deficits from surgery.