title: Unusual subacute diencephalic edema associated with a trapped fourth ventricle: resolution following foramen magnum decompression.
abstract: BACKGROUND
  A 4-year-old girl with a ventriculoperitoneal shunt presented to us with complaints of ataxia and altered consciousness. These symptoms were subacute at onset and progressive in nature.
  
  
  METHODS
  Radiological evaluation revealed a trapped fourth ventricle with brainstem compression, associated with abnormal diffuse diencephalic signal changes compatible with edema. The entrapment was managed by foramen magnum decompression, resulting in complete symptom resolution and improvement in the abnormal magnetic resonance findings.
  
  
  CONCLUSIONS
  While trapped fourth ventricle is a well-described entity, we could not find a similar reported case where such an acute clinical syndrome was associated with such a distinct radiological picture.
  
  
  CONCLUSIONS
  In this paper, we review the pre-morbid history, clinical syndrome, and imaging. We then discuss possible mechanisms, their implications on decision-making, and the preferred modes of treatment.
authors.affiliation: Department of Pediatric Neurosurgery, Dana Children's Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv University, Tel Aviv 64239, Israel.
authors.forename: Suhas
authors.initials: S
authors.lastname: Udayakumaran
authors.forename: Xiao
authors.initials: X
authors.lastname: Bo
authors.forename: Liat
authors.initials: L
authors.lastname: Ben Sira
authors.forename: Shlomi
authors.initials: S
authors.lastname: Constantini
mesh_terms: D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D001927:Brain Diseases / Q000150:complications / Q000473:pathology* / Q000601:surgery; D001929:Brain Edema / Q000209:etiology / Q000473:pathology* / Q000601:surgery; D002675:Child, Preschool; D019299:Decompression, Surgical; D005260:Female; D005500:Follow-Up Studies; D005539:Foramen Magnum / Q000473:pathology* / Q000601:surgery*; D020546:Fourth Ventricle / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome