title: Lack of causal association between spontaneous intracranial hypotension and cranial cerebrospinal fluid leaks.
abstract: OBJECTIVE
  Spontaneous intracranial hypotension is an important cause of headaches and an underlying spinal CSF leak can be demonstrated in most patients. Whether CSF leaks at the level of the skull base can cause spontaneous intracranial hypotension remains a matter of controversy. The authors' aim was to examine the frequency of skull base CSF leaks as the cause of spontaneous intracranial hypotension.
  
  
  METHODS
  Demographic, clinical, and radiological data were collected from a consecutive group of patients evaluated for spontaneous intracranial hypotension during a 9-year period.
  
  
  RESULTS
  Among 273 patients who met the diagnostic criteria for spontaneous intracranial hypotension and 42 who did not, not a single instance of CSF leak at the skull base was encountered. Clear nasal drainage was reported by 41 patients, but a diagnosis of CSF rhinorrhea could not be established. Four patients underwent exploratory surgery for presumed CSF rhinorrhea. In addition, the authors treated 3 patients who had a postoperative CSF leak at the skull base following the resection of a cerebellopontine angle tumor and developed orthostatic headaches; spinal imaging, however, demonstrated the presence of a spinal source of CSF leakage in all 3 patients.
  
  
  CONCLUSIONS
  There is no evidence for an association between spontaneous intracranial hypotension and CSF leaks at the level of the skull base. Moreover, the authors' study suggests that a spinal source for CSF leakage should even be suspected in patients with orthostatic headaches who have a documented skull base CSF leak.
authors.affiliation: Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA. schievinkw@cshs.org
authors.forename: Wouter I
authors.initials: WI
authors.lastname: Schievink
authors.forename: Marc S
authors.initials: MS
authors.lastname: Schwartz
authors.forename: M Marcel
authors.initials: MM
authors.lastname: Maya
authors.forename: Franklin G
authors.initials: FG
authors.lastname: Moser
authors.forename: Todd D
authors.initials: TD
authors.lastname: Rozen
mesh_terms: D015984:Causality; D002528:Cerebellar Neoplasms / Q000601:surgery; D002530:Cerebellopontine Angle / Q000601:surgery; D065634:Cerebrospinal Fluid Leak; D002559:Cerebrospinal Fluid Rhinorrhea / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D003937:Diagnosis, Differential; D005260:Female; D006261:Headache / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D019585:Intracranial Hypotension / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009192:Myelography; D009464:Neuroma, Acoustic / Q000601:surgery; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology; D019291:Skull Base; D014057:Tomography, X-Ray Computed