title: Bilateral abducent and facial nerve palsies following fourth ventricle shunting: two case reports.
abstract: METHODS
  Treatment of isolated fourth ventricle syndrome is difficult and there is no widely agreed method. Fourth ventriculo-peritoneal shunting is the most commonly utilized procedure for the management of this syndrome. Complications from shunting are common and are usually related to malfunction, infection, dislocation and overdrainage. We present two unusual cases in which both patients developed bilateral abducens and facial nerve palsies following shunting of an isolated fourth ventricle. Magnetic resonance imaging (MRI) in both cases revealed collapse of the fourth ventricles with downward displacement of the brain stem. In the first case the trans-tentorial pressure difference was equilibrated with the aid of a "Y" connector between the supratentorial and infratentorial shunts, with full recovery of the neurological deficits; in the second case this approach failed and following a complicated neurosurgical course successful endoscopic aqueductal stenting was performed.
  
  
  CONCLUSIONS
  Pathogenesis of cranial nerve palsies following fourth ventricle shunting and the rationale of treatment are discussed and the literature is reviewed.
authors.affiliation: Department of Neurosurgery, Second University Hospital of Naples, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Spennato
authors.forename: Donncha F
authors.initials: DF
authors.lastname: O'Brien
authors.forename: John P
authors.initials: JP
authors.lastname: Fraher
authors.forename: Conor L
authors.initials: CL
authors.lastname: Mallucci
mesh_terms: D020434:Abducens Nerve Diseases / Q000473:pathology / Q000601:surgery*; D000293:Adolescent; D002648:Child; D005155:Facial Nerve Diseases / Q000473:pathology / Q000601:surgery*; D005260:Female; D020546:Fourth Ventricle / Q000473:pathology / Q000601:surgery*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D016896:Treatment Outcome; D017287:Ventriculoperitoneal Shunt / Q000379:methods*