INTRA-OPERATIVE SPINAL CORD MONITORING DURING SURGERY FOR SCOLIOSIS USING SOMATOSENSORY EVOKED POTENTIALS

Abstract

The method of intra-operative monitoring of spinal cord function by spinal somatosensory evoked potentials (SEP), as used at the Royal Alexandra Hospital for Children during surgery for scoliosis is described. Using a non-polarizable Pt spinal epidural electrode, SEP elicited by tibial and peroneal nerve stimulation in the popliteal fossa are recorded proximal to the level of spinal correction. The large amplitude and discrete waveform of the SEP enable rapid signal acquisition and easy interpretation. The spinal SEP is stable under both therapeutic hypotension and general anesthesia. Electrophysiological monitoring has now superceded the wake-up test as an index of spinal cord function during corrective surgery for scoliosis.