The efficacy of intraoperative neuromonitoring, including triggered electromyography, in intradural extramedullary spine tumors: a successful case study

Abstract

A male patient with intradural-extramedullary (IDEM) tumor at T9-L3 level underwent surgical tumor removal, supported by multimodal intraoperative neurophysiological monitoring (IONM), which included evoked potentials, free-running and triggered electromyography. During laminectomy, motor evoked potentials were preserved, while the somatosensory evoked potentials in right tibial nerve decreased by more than 50% compared to baseline. Additionally, during tumor retraction, free running electromyography revealed the B-train with spikes in left abductor hallucis and tibialis anterior muscles. Furthermore, triggered electromyography was employed to avoid nerve root sacrifice. The patient, under this comprehensive multimodal monitoring, experienced no postoperative neurological deterioration. This case report highlights the importance of multimodal IONM in IDEM tumor surgeries, especially emphasizing the critical role of electromyography.