The Impact of Intraoperative Monitoring on Extent of Resection and Long-Term Neurological Outcomes: A Series of 39 Intramedullary Ependimomas

Özet

AIM: To analyze the impact of intraoperative neurophysiological monitoring (IONM) on the extent of removal and long-termneurological outcomes in a series of grade II ependymomas.MATERIAL and METHODS: We retrospectively reviewed 88 consecutive patients who underwent surgical resection of anintramedullary spinal cord tumor (IMSCT) at the Clinic of Neurosurgery of the Clinical Center of Serbia in Belgrade between January2012 and December 2017. In all, 39 patients (25 males and 14 females; mean age 46.16 years) with grade II ependymomas wereenrolled in this study; the mean follow-up time was 49.84 months. The modified McCormick Scale (mMCS) was used to assess theshort- and long-term outcomes, and the patients were divided into two groups based on whether they underwent IONM.RESULTS: The gross-total removal rate was 89.7%, and it was not influenced by use of IONM, location or tumor size. Uponadmission,43.2% of the patients were dependent (grades IV and V), while 56.8% were independent (grades I, II and III), according tothe mMCS. After 3 months of follow-up, 76.9% of the patients maintained or improved their neurological status, but this percentagewas reduced after long-term follow-up.CONCLUSION: Total surgical resection with good neurological outcomes can be achieved in the vast majority of patients with gradeII ependymomas; it is important to emphasize that the use of IONM allows acceptable extent of resection and provides better resultsin terms of functional outcomes, with lower morbidity rates. Therefore, no correlation was demonstrated between the decrease inthe basal amplitudes of IONM and D-waves and poor neurological outcomes.