Evoked potentials recorded from scalp and spinous processes during spinal column surgery

Area of Science:

• Neuroscience
• Spinal Surgery
• Evoked Potentials

Background:

• Spinal column curvature correction surgery carries risks to spinal cord function.
• Monitoring nerve conduction during surgery is crucial for patient safety.
• Peroneal nerve evoked potentials offer a potential method for intraoperative neuromonitoring.

Purpose of the Study:

• To evaluate the utility of peroneal nerve evoked potentials for monitoring spinal cord afferent pathways during spinal surgery.
• To characterize the characteristics of spinal potentials recorded at multiple levels.
• To assess the stability of scalp-recorded potentials under general anesthesia.

Main Methods:

• Simultaneous recording of peroneal nerve evoked potentials from scalp and spinal electrodes at multiple levels in 43 patients undergoing spinal surgery.
• Analysis of latency, amplitude, and waveform characteristics of recorded potentials.
• Assessment of potential stability under halogenated general anesthesia.

Main Results:

• Spinal potentials showed progressive latency increases rostrally.
• Distinct potential components were identified, suggesting presynaptic (diphasic) and postsynaptic origins.
• Scalp-recorded potentials (PV-N1) exhibited stable amplitudes and latencies during anesthesia, indicating reliability.
• Selective filtering may differentiate axonal and synaptic activities.

Conclusions:

• Scalp-recorded peroneal nerve evoked potentials (PV-N1) are a reliable indicator of spinal cord afferent pathway conduction during spinal surgery.
• Understanding the components of spinal potentials aids in interpreting neuromonitoring data.
• These findings support the use of evoked potentials for intraoperative neuromonitoring in spinal procedures.