C2 Nerve Sheath Tumors: An Analysis of Radiological – Intraoperative Concordance for Intradural Extension and Systematic Review

Abstract

Background: Nerve sheath tumors (NSTs) of C2 nerve-root are clinically and radiologically distinct from NSTs of rest of the spine. On imaging, they appear to have a major intradural component in addition to the large extradural part. Thus, they may require durotomy with its possible added complications. Objective: The aim of this study is to evaluate the radiological – intra-operative discordance for intradural component and need for tailored durotomy for complete resection of C2 NSTs. Material and Methods: We retrospectively analyzed 14 consecutively operated patients of C2 NSTs over the past 10 years (2013-2023). Dura was opened in patients where there was a radiological or intra-operative suspicion of intradural extension. Results: Mean(±SD) age at presentation was 37.5(±13) years, with no gender predominance (Male:Female-1.3:1). Dura was opened in 7(50%) patients. On preoperative radiological study, all the patients had a dominant extradural tumor, while 7(50%) patients appeared to have an intradural tumor extension also. Intra-operatively, 5(35.7%) of these 7 patients had only extradural component, while 2(14.3%) patients had an intradural extension. 7(50%) patients had extradural tumor radiologically, while only one patient was found to have a small intradural extension intraoperatively. Thus, only 21.4% of the patients (n=3) were found to have an intradural extension as against 50%(n=7) predicted on imaging. Post-operatively there was clinical improvement in all 14 patients (100%). Conclusions: Due to radiological and intra-operative discordance in intradural tumor extension, decision for midline durotomy should be taken following excision of extradural component. Thus, limiting the number of unnecessary midline-durotomies.