title: Endoscopic treatment of isolated fourth ventricle:  clinical and radiological outcome.
abstract: BACKGROUND
  Treatment of an isolated fourth ventricle should be considered when clinical symptoms or a significant mass effect occur.
  
  
  OBJECTIVE
  To report clinical and radiographic outcomes after endoscopic transaqueductal or transcisternal stent placement into the fourth ventricle.
  
  
  METHODS
  In 19 patients (age, 34th week of gestation-20 years; median age, 17.5 months), 22 endoscopic procedures were performed. Either an aqueductoplasty or, in cases with a supratentorially extended fourth ventricular component, an interventricular fenestration was performed. In all patients, a stent connected to the cerebrospinal fluid--diverting shunt was placed through the fenestration. Surgical complications and radiological and clinical outcomes are reported.
  
  
  RESULTS
  All 19 patients had a mean follow-up of 26.9 ± 18.2 months. No persisting neurological complications were observed; 27.3% of patients experienced complete resolution of presenting symptoms, whereas 68.3% demonstrated partial resolution. Symptoms with short duration (< 4 weeks) resolved completely, whereas long-standing symptoms partially improved. Short-term shunt complications (n = 2; insufficient catheter placement and subdural hygroma) and a need for long-term stent revisions (n = 3; stent retraction and shunt revision for other causes) were observed. The mean fourth ventricular volume was reduced after surgery (44.2 ± 25.8 to 23.1 ± 21.9 mL; P < .01). Pontine diameter increased from 0.9 ± 0.3 to 1.2 ± 0.3 cm (P < .01) after surgery. Both effects were still demonstrated on later radiological follow-up of 24.4 ± 14.2 months (fourth ventricular size, 24.7 ± 28.1 mL; P < .01; pontine diameter, 1.3 ± 0.3 cm; P < .01).
  
  
  CONCLUSIONS
  The clinical and radiological outcomes after endoscopic aqueductoplasty and interventriculostomy in children with an isolated fourth ventricle indicate that this procedure is feasible, effective, and safe.
authors.affiliation: Department of Pediatric Neurosurgery, Charite University Hospital Berlin, Berlin, Germany. matthias.schulz@waikatodhb.health.nz
authors.forename: Matthias
authors.initials: M
authors.lastname: Schulz
authors.forename: Leonie
authors.initials: L
authors.lastname: Goelz
authors.forename: Birgit
authors.initials: B
authors.lastname: Spors
authors.forename: Hannes
authors.initials: H
authors.lastname: Haberl
authors.forename: Ulrich-Wilhelm
authors.initials: UW
authors.lastname: Thomale
mesh_terms: D002557:Cerebrospinal Fluid Shunts; D002648:Child; D002675:Child, Preschool; D005260:Female; D020546:Fourth Ventricle / Q000473:pathology / Q000601:surgery*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D008297:Male; D044583:Neuroendoscopy / Q000379:methods*; D014696:Ventriculostomy / Q000379:methods*; D055815:Young Adult