title: Spontaneous sphenoid lateral recess cerebrospinal fluid leaks arise from intracranial hypertension, not Sternberg's canal.
abstract: BACKGROUND
  Spontaneous cerebrospinal fluid (CSF) leaks/encephaloceles are proven to be associated with intracranial hypertension by objective measurements of CSF pressure during or following endoscopic repair. A common area of involvement is a pneumatized lateral recess of the sphenoid (LRS) sinus, where prolonged intracranial pressures lead to arachnoid pits and subsequent development of skull-base defects. Even though the LRS is never present at birth, a "congenital" cause of these leaks due to a persistent Sternberg's (lateral craniopharyngeal) canal continues to be erroneously perpetuated in the literature. The objective of this study was to eliminate the myths defining these leaks as congenital in nature.
  
  
  METHODS
  Evaluation of LRS CSF leaks present within a multiinstitutional case series was performed. Data regarding demographics, body mass index (BMI), radiologic evaluation of intracranial hypertension, and direct intracranial pressure measurements (when available) were collected.
  
  
  RESULTS
  Data evaluation identified 77 LRS CSF leaks in 59 patients (mean age 52 years). Obesity was present in 83% of individuals (mean BMI 36) and 81% were females. Radiologic evidence of intracranial hypertension (eg, empty sella, dilated optic nerve sheaths, and scalloped/attenuated bone) was present on 96% of preoperative computed tomography (CT) and/or magnetic resonance imaging (MRI) scans. Opening or postsurgical lumbar drain or ventriculostomy pressure measurements were elevated in 95% of patients (mean 27.7; range, 9-50 cmH2 O).
  
  
  CONCLUSIONS
  This study provides objective evidence that LRS CSF leaks are secondary to erosions from intracranial hypertension and refutes the myth regarding a congenital origin from Sternberg's canal.
authors.affiliation: Department of Surgery, Division of Otolaryngology, Medical University of South Carolina, Charleston, SC.
authors.forename: Elisa
authors.initials: E
authors.lastname: Illing
authors.forename: Rodney J
authors.initials: RJ
authors.lastname: Schlosser
authors.forename: James N
authors.initials: JN
authors.lastname: Palmer
authors.forename: Joel
authors.initials: J
authors.lastname: Curé
authors.forename: Nyssa
authors.initials: N
authors.lastname: Fox
authors.forename: Bradford A
authors.initials: BA
authors.lastname: Woodworth
mesh_terms: D065634:Cerebrospinal Fluid Leak; D002559:Cerebrospinal Fluid Rhinorrhea / Q000175:diagnosis* / Q000209:etiology; D003937:Diagnosis, Differential; D004724:Endoscopy; D005260:Female; D006801:Humans; D019586:Intracranial Hypertension / Q000150:complications / Q000175:diagnosis* / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009421:Nervous System Malformations / Q000150:complications / Q000175:diagnosis*; D011183:Postoperative Complications / Q000175:diagnosis*; D011877:Radionuclide Imaging; D019291:Skull Base / Q000601:surgery; D013101:Sphenoid Sinus / Q000000981:diagnostic imaging / Q000473:pathology*; D014057:Tomography, X-Ray Computed
keywords: CSF leak; Sternberg's canal; endoscopic surgery; intracranial hypertension; lateral craniopharyngeal canal; lateral recess; sphenoid sinus; spontaneous