Background: Intradural extramedullary spinal cord tumors (ID-EMSCT) make up 40% of all spinal neoplasms. Resection of these tumors is mostly conducted using intraoperative neuromonitoring (IONM). However, the literature shows heterogenous data on its added value for ID-EMSCT. The aim of this study is to define sensitivity and specificity of IONM in ID-EMSCT resection and to study possible correlations between preoperative, intraoperative, and postoperative variables and neurologic outcomes after ID-EMSCT resection. Methods: Data of patients undergoing ID-EMSCT surgeries with IONM from January 2012 until July 2019 were examined. Using neurologic status 6 weeks and 1 year postoperatively, sensitivity and specificity for IONM were calculated. IONM test results and neurologic outcomes were paired to preoperative, intraoperative, and postoperative parameters. Results: Data of 78 patients were analyzed. 6 weeks postoperatively, 14.10% of patients had worse neurologic status, decreasing to 9.84% 1 year postoperatively. Multimodal IONM showed a sensitivity of 0.73 (95% confidence interval [CI], 0.39–0.94) and a specificity of 0.78 (95% CI, 0.66–0.87) after 6 weeks, and a sensitivity of 1.00 (95% CI, 0.54–1.00) and a specificity of 0.71 (95% CI, 0.57–0.82) after 1 year. Conclusions: IONM yielded high to perfect sensitivity and high specificity. However, IONM signals did not always determine the extent of resection, and false-positive results did not always result in incomplete tumor resections, because of surgeons overruling IONM. Therefore, IONM cannot fully replace clinical judgment and other perioperative information.

Extramedullary tumor, IONM, Neurologic function, Neuromonitoring, Neurosurgery, Spinal cord tumor,
World Neurosurgery
Department of Anesthesiology

van der Wal, E.C. (Ewout C.), Klimek, M, Rijs, K. (Koen), Scheltens-De Boer, M, Biesheuvel, K, & Harhangi, B.S. (2021). Intraoperative Neuromonitoring in Patients with Intradural Extramedullary Spinal Cord Tumor: A Single-Center Case Series. World Neurosurgery. doi:10.1016/j.wneu.2020.12.099