title: Increasing chronic subdural hematoma after endoscopic III ventriculostomy.
abstract: OBJECTIVE
  Endoscopic III ventriculostomy (ETV) is an effective and a rather safe treatment for noncommunicating hydrocephalus secondary to aqueductal stenosis and other obstructive pathologies. Though not devoid of risk, ETV is increasingly replacing shunt operations, and it prevents related complications, including overdrainage.
  
  
  METHODS
  We report a rare case of a large chronic subdural hematoma (ChSDH) after ETV in a patient with aqueductal stenosis. Three weeks after he was shunted elsewhere, he presented to us with clinical symptoms of intracranial hypotension and overdrainage. ETV was performed and the shunt removed uneventfully. On routine postoperative MRI a few weeks later, a large ChSDH was noted, the patient being totally asymptomatic. Since the ChSDH grew significantly, causing a mass effect on the follow-up MRI, it was finally drained. Large and increasing ChSDHs have previously been reported secondary to overdrainage after shunt placement, but not after ETV.
  
  
  CONCLUSIONS
  We conclude that though rare, a ChSDH may evolve even after ETV, if there is a substantial decrease in previously elevated intracranial pressure.
authors.affiliation: Division of Pediatric Neurosurgery, Dana Children's Hospital, Tel-Aviv Sourasky Medical Center, Israel.
authors.forename: L
authors.initials: L
authors.lastname: Beni-Adani
authors.forename: V
authors.initials: V
authors.lastname: Siomin
authors.forename: Y
authors.initials: Y
authors.lastname: Segev
authors.forename: S
authors.initials: S
authors.lastname: Beni
authors.forename: S
authors.initials: S
authors.lastname: Constantini
mesh_terms: D000328:Adult; D004724:Endoscopy; D020200:Hematoma, Subdural, Chronic / Q000175:diagnosis* / Q000601:surgery; D006801:Humans; D006849:Hydrocephalus / Q000601:surgery*; D019585:Intracranial Hypotension / Q000175:diagnosis / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D011183:Postoperative Complications / Q000175:diagnosis* / Q000601:surgery; D012086:Reoperation; D014696:Ventriculostomy