J Neurol Surg B Skull Base 2016; 77 - P032
DOI: 10.1055/s-0036-1579979

Non-Random Spatial Clustering of Spontaneous Anterior Fossa Meningoceles and Encephaloceles Causing Cerebrospinal Fluid Leak

Richard D. Murray 1, Rachel Friedlander 1, Samuel Hanz 1, Vijay K. Anand 1, Theodore H. Schwartz 1
  • 1New York Presbytarian/ Weill Cornell Brain and Spine, New York, New York, United States

Objective: The anterior skull base is a common site for spontaneous cerebrospinal fluid (CSF) fistula formation. The exact sites of origin determine the surgical approaches to these lesions. We aim to demonstrate the spatial distribution of these lesions and statistically confirm sites of predilection.

Methods: Retrospective review of a prospectively acquired surgical database involving the endonasal endoscopic repair of (n = 19) consecutive spontaneous CSF fistula cases. Exact anatomic site of defects were located on radiographic imaging and this was superimposed on a theoretical 4x2 grid representing the anterior midline skull base. This grid was then used to statistically analyze the distribution of defects. Monte Carlo simulation was performed to further strengthen statistical support of conclusions.

Results: In our dataset, the cribriform plate was the most likely site of origin of spontaneous CSF leaks. Chi-square test yielded a p value of 0.035. On subsequent Monte Carlo simulation a p value of 0.034 was achieved, further supporting this observation.

Conclusions: The most likely site of origin of the spontaneous CSF leaks of the anterior midline skull base is the cribriform plate region. This is in opposition to iatrogenic lesions, which have a higher likelihood of occurring in the posterior ethmoid region.