Medical Science Research Bulletin

Multimodal intraoperative neuromonitoring (IONM) plays a critical role in enhancing the safety of posterior fossa and cerebellopontine angle (CPA) surgeries, where dense neurovascular structures place patients at high risk of neurological deficits. This case series evaluates the utility of combined corticobulbar motor evoked potentials (CoMEP), somatosensory evoked potentials (SSEP), and transcranial motor evoked potentials (TcMEP) in assessing intraoperative neural integrity and predicting postoperative outcomes. Six patients undergoing posterior fossa procedures were monitored using standardized anesthetic and neuromonitoring protocols, with baseline, intraoperative, and closure recordings compared for amplitude and latency changes. Stable CoMEP, SSEP, and TcMEP signals were associated with intact postoperative neurological function, while altered responses correlated with transient or persistent cranial nerve deficits, particularly involving facial and lower cranial nerves. These findings support multimodal IONM as an essential adjunct in posterior fossa surgery, enabling early detection of neural compromise and timely corrective surgical interventions.

Multimodal intraoperative neuromonitoring; Posterior fossa surgery; Corticobulbar motor evoked potentials; Somatosensory evoked potentials; Transcranial motor evoked potentials; Cerebellopontine angle tumors

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