Relevance of intraoperative motor evoked potentials and D-wave monitoring for the resection of intramedullary spinal cord tumors in children

The purpose of this study was to evaluate the reliability of motor evoked potentials (MEP), somatosensory evoked potentials (SSEP), and D-wave monitoring as predictors of postoperative neurological deficits in pediatric patients undergoing resection of intramedullary spinal cord tumors (IMSCTs). Additionally, we aimed to determine whether alerts in the intraoperative neurophysiological monitoring (IONM) influenced the extent of resection (EOR). A retrospective analysis of the pediatric patients who underwent resection of IMSCT between March 2010 and April 2021 with an IONM guidance was performed. IONM alerts were recorded and correlated with patients’ clinical status at discharge. Twenty three pediatric patients were included. MEP and SSEP were successfully elicited in all patients, while D-wave monitoring was feasible for 14 of them (60.9%). Significant IONM alerts occurred in 6 individuals (26.1%) with monitorable MEP and SSEP and 2 patients with monitorable D-waves (14.3%). The sensitivity, specificity, positive predictive value, and negative predictive value accounted for 100%, 81.8%, 20%, 100% for MEP, 100%, 92.3%, 50%, 100% for D-wave, and 50%, 81%, 20%, 94.44% for SSEP, respectively. Both MEP ( p < 0.001) and D-wave monitoring ( p < 0.001) accurately predicted postoperative motor deficits, while SSEP failed to provide significant accuracy regarding sensory deficits ( p = 0.491). Gross-total tumor resection was performed in 29.4% of patients without IONM alerts and 33.3% of patients with IONM alerts, indicating that IONM alerts did not limit the EOR ( p = 0.0857). MEP and D-wave monitoring can be perceived as reliable IONM modalities in pediatric IMSCTs surgery. Caution is needed with the implementation of SSEP to guide surgical decisions.