Little Insights from Big Data: Risk and Misconception regarding Cerebrospinal Fluid Leak after Resection of Skull Base Meningiomas

Introduction: Neurosurgical dogma regarding risk factors for cerebrospinal fluid (CSF) leak holds that a broad range of comorbidities place patients at increased risk for this complication. Although rational arguments and extensive empiric experience such as retrospective patient series have been published to explain these theoretical pathophysiological relationships, many have not been explicitly confirmed using large, multicenter, national surgical outcomes databases.

Methods: A retrospective case-control analysis was performed using patients from the ACS-NSQIP registry from 2012–2014 with a diagnosis of benign neoplasm of cerebral meninges and Current Procedural Terminology (CPT) codes confirming open resection of a skull base lesion. The primary outcome of interest was CSF leak; exposures tested included smoking status, alcohol consumption, diabetes, and steroid exposure.

Results: 304 unique individual patients were identified. Positive smoking within the past year status was reported in 34 (11%), which was not significantly associated with increased risk of CSF leak (p = 0.7). Recent alcohol consumption was documented in 273 (90%), and there was no significant difference in rate of CSF leak (p = 0.3). Chronic systemic steroid exposure within 30 days prior to surgery was noted in 29 (10%), without evidence of a significantly heightened incidence of CSF leak (p = 0.9). Diabetes mellitus status was confirmed in 40 patients (20%), of whom 16 experienced CSF leaks (40%)—a significant increase from the non-diabetic patient group (p = 0.006).

Conclusion: In a large, multicenter, national surgical outcomes database, diabetes is confirmed to be associated with a significantly increased risk of CSF leak among patients who undergo open resection of skull base meningiomas—a findings that is most likely attributable to the disease’s well-characterized impacts on wound healing and inflammation in general. Surprisingly, associations between preoperative exposure to cigarettes, alcohol, or systemic steroids and postoperative CSF leaks were not found to be significant in this same analysis. Further study is required to better characterize the complex relationships between these presumed risk factors and postoperative outcomes in the full range of skull base operations, with a particular eye toward the potential advantages and limitations of national outcomes databases.