title: Postsurgical intracranial hypotension: diagnostic and prognostic imaging findings.
abstract: OBJECTIVE
  CSF loss with consecutive intracranial hypotension has been discussed as a possible pathogenetic mechanism in poor clinical outcome after uneventful neurosurgery and appears to be correlated to specific imaging findings. The purpose of this study was to describe the clinical and imaging findings of symptomatic intracranial hypotension likely induced by wound suction drainage.
  
  
  METHODS
  This is a review of previously published cases of patients in whom this condition developed after uneventful intracranial surgery. We performed an analysis of 3 more cases, of which 2 occurred after spinal surgery with accidental dural opening.
  
  
  RESULTS
  Sixteen patients who remained unconscious or did not become fully responsive after surgery showed symmetric bilateral thalamic/basal ganglia signal intensity changes on CT and MR imaging studies. Of these 16 patients, 4 died and 2 also had brain stem signal intensity changes. All patients had rapid and distinct intraoperative and postoperative CSF loss documented on CT and/or MR imaging studies by a transient increase of the sag ratio, defined as maximal anteroposterior midbrain diameter by maximal bipeduncular diameter.
  
  
  CONCLUSIONS
  The clinical course and typical MR imaging findings characterize the disease entity postsurgical intracranial hypotension. These findings also underline the potential danger of wound suction drainage in the case of possible CSF loss.
authors.affiliation: Department of Radiology, University of Bonn Medical Center, Bonn, Germany.
authors.forename: D R
authors.initials: DR
authors.lastname: Hadizadeh
authors.forename: A
authors.initials: A
authors.lastname: Kovács
authors.forename: H
authors.initials: H
authors.lastname: Tschampa
authors.forename: R
authors.initials: R
authors.lastname: Kristof
authors.forename: J
authors.initials: J
authors.lastname: Schramm
authors.forename: H
authors.initials: H
authors.lastname: Urbach
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction; D005260:Female; D006801:Humans; D019585:Intracranial Hypotension / Q000175:diagnosis* / Q000209:etiology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000009:adverse effects; D011379:Prognosis