====== Transcranial motor evoked potentials ======

see [[Transcranial motor evoked potential monitoring]].
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====== Anesthetic requirements ======
In addition to [[evoked potential]] anesthetic requirements, the neuromuscular blockade must be minimized to permit ≥ 2 out of 4 twitches.

AKA [[motor evoked potentials]] (MEP): transcranial electrical or magnetic stimulation of [[motor cortex]] and descending motor axons with a recording of motor potentials from distal spinal cord or muscle groups. Using direct [[Electrostimulation]] is limited in awake patients by local pain. Due to the large potential, the acquisition time is shorter and feedback to the surgeon is almost immediate. However, due to patient movement from the muscle contractions, continuous recording is usually not possible (except with monitoring the response over the spinal cord). Useful for surgery involving the spinal cord (cervical or thoracic), no utility for lumbar spine surgery. Seizures occur rarely, usually in patients with increased seizure risk and with high-rate stimulation frequency.

Contraindications to MEP: history of epilepsy/seizures past surgical skull defects metal in head or neck use special care with implanted electronic devices