LAUSR

BACKGROUND Intradural extramedullary spinal cord tumors (ID-EMSCT) take up 40% of all spinal neoplasms. Resection of these tumors is mostly conducted using intraoperative neuromonitoring (IONM). However, literature shows heterogenous data on its added value for ID-EMSCT. OBJECTIVE To define sensitivity and specificity of IONM in ID-EMSCT resection, and to study possible correlations between pre-, intra-, and postoperative variables and neurological outcomes after ID-EMSCT resection. METHODS Data of patients undergoing ID-EMSCT surgeries with IONM from January 2012 until July 2019 was examined. Using neurological status 6 weeks and 1 year postoperatively, sensitivity and specificity for IONM was calculated. IONM test results and neurological outcomes were paired to pre-, intra- and postoperative parameters. RESULTS Data of 78 patients were analyzed. 6 weeks postoperatively, 14.10% of patients had worse neurological status, decreasing to 9.84% 1 year postoperatively. Multimodal IONM showed a sensitivity of 0.73 (95%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. CONCLUSION IONM yielded high to perfect sensitivity and high specificity. However, IONM signals did not always determine the extent of resection, and false positives did not always result in incomplete tumor resections, due to surgeons overruling IONM. Therefore, IONM cannot fully replace clinical judgement and other perioperative information.