SEP Montage Variability Comparison during Intraoperative Neurophysiologic Monitoring

Area of Science:

• Neurosurgery
• Neurophysiology
• Spinal Surgery

Background:

• Intraoperative monitoring (IOM) assesses neural structures at risk during spinal surgery.
• Somatosensory evoked potentials (SEPs) are the primary IOM modality.
• SEP stability can be compromised by surgical factors.

Purpose of the Study:

• To evaluate SEP recording stability across multiple montages during instrumented spinal surgeries.
• To identify the optimal combination of montages for maximizing monitorable surgeries.
• To enhance the reliability of IOM and reduce false positive alerts.

Main Methods:

• Prospective review of SEP recordings during instrumented spinal surgeries.
• Analysis of multiple cortical SEP recording montages at baseline and throughout procedures.
• Evaluation of SEP stability in patients with neurological and neuromuscular conditions.

Main Results:

• Multiple SEP montages are necessary to reduce non-monitorable cases and improve IOM reliability.
• The Cz-C4/Cz-C3 (Cz-Cc) montage demonstrated the highest reliability and stability.
• This preferred montage can help minimize false positive warnings to surgeons.

Conclusions:

• Utilizing multiple SEP montages is crucial for effective intraoperative monitoring in spinal surgery.
• The Cz-Cc montage is recommended as the most stable and reliable option.
• Optimizing montage selection enhances surgical safety and monitoring accuracy.