Intradural Spinal Tumors-Review of Postoperative Outcomes Comparing Intramedullary and Extramedullary Tumors from a Single Institution's Experience.

BACKGROUND: Intradural spinal tumors are rare and can be classified into extramedullary or intramedullary. They commonly present with symptoms such as intractable back pain or neurologic deficits. We retrospectively reviewed 91 cases of intradural spinal tumors that underwent surgery in our institution from 2011 to 2016 and assessed their clinical outcomes. The majority of intradural tumors were extramedullary (89%), and the most common pathology was schwannoma (38.5%) followed by meningioma (29.7%). Comparing extramedullary versus intramedullary tumors, both groups experienced similar improvement in neurologic status post surgery (92.6% vs. 90%, P = 0.77). We achieved gross total resection in the majority of patients with both extramedullary and intramedullary tumors (65.4% vs. 70%, P = 0.91). Patients younger than 65 years (odds ratio [OR] 4.40, confidence interval [CI] 0.72-26.9, P = 0.11) and those who had complete resection of tumor (OR 2.92, CI 0.61-14.0, P = 0.18) were associated with higher odds of improved clinical outcomes, but the results were not statistically significant. The use of intraoperative neurophysiologic monitoring was not associated with improved neurologic outcomes compared with cases where it was not used (OR 0.56, CI 0.10-3.05, P = 0.50).