Intraoperative Neuromonitoring

What it is

IONM is performed by a trained neurophysiologist who records several types of signals throughout the operation: somatosensory evoked potentials (SSEP) that reflect sensory pathways, motor evoked potentials (MEP) that reflect motor pathways, and electromyography (EMG) that watches individual nerve roots.

Electrodes placed before incision establish a baseline; any meaningful change during surgery is communicated to Dr. Choi immediately, while correction is still possible.

How it supports precision

The spinal cord cannot signal pain under anesthesia, so without monitoring the team has no direct way to know how it is tolerating retraction, repositioning, or correction. IONM provides that missing feedback — an early warning when cord or nerve function changes during a maneuver.

When signals change, the surgeon can pause, adjust, revise a correction, or check blood pressure and positioning — turning what might have been an unrecognized injury into a reversible moment.

Its limits

Monitoring reports function; it does not prevent injury on its own. Its value depends entirely on the team recognizing a change quickly and knowing which responses are likely to restore the signal. Anesthesia choices and body temperature also affect the readings and must be managed so the data stays trustworthy.

Not every operation requires IONM. Its use is matched to the case — the level, the proximity to the cord, and the type of correction — rather than applied by default.