title: Description of endoscopic ventricular anatomy in myelomeningocele.
abstract: OBJECTIVE
  The purpose of this work is to present our endoscopic neuroanatomical findings of a series of myelomeningocele and hydrocephalus patients, treated with endoscopic third ventricular cisternostomy (ETVC), in order to describe ventricular configuration abnormalities in this group of patients, in which this neurosurgical procedure has limited performance.
  
  
  METHODS
  We checked the videos of 10 endoscopic third ventricular cisternostomies of myelomeningocele patients taken during 24 months as from December 1998. A previous guideline is designed to record anatomic variables in the lateral ventricles, IIIrd ventricle, and basal cisterns. The topic is analyzed in view of the necropsy and imaging background data.
  
  
  RESULTS
  The ETVC of lateral ventricles showed: absence of septum (9/10); absence of anteroseptal vein (8/10); absence of choroid plexus and thalamostriate vein (0/10); absence of fornix (1/10): small foramen of Monro (4/10). The ETVC of the IIIrd ventricle showed: impossibility of recognizing any mammillary bodies (4/10); presence of septations (5/10); presence of atypical veins in the floor (6/10); translucent floor (5/10); floor umbilications (5/10); absence of infundibulum (4/10); arachnoid adherences (7/10); and visual contact of basilar artery (4/10).
  
  
  CONCLUSIONS
  There are categorical structural alterations in the ventricular system of myelomeningocele patients that are well correlated with previous necropsy and imaging reports. The ventricular system of dysraphic children presents severe anatomic alterations, which alter the reference points of the classical endoscopic third ventricular cisternostomy.
authors.affiliation: Servicio de Neurocirugia del Hospital Van Buren Hospital, Universidad de Valparaiso, Valparaiso, Chile. apavez@ucn.cl
authors.forename: A
authors.initials: A
authors.lastname: Pavez
authors.forename: C
authors.initials: C
authors.lastname: Salazar
authors.forename: R
authors.initials: R
authors.lastname: Rivera
authors.forename: J
authors.initials: J
authors.lastname: Contreras
authors.forename: A
authors.initials: A
authors.lastname: Orellana
authors.forename: C
authors.initials: C
authors.lastname: Guzman
authors.forename: O
authors.initials: O
authors.lastname: Iribarren
authors.forename: H
authors.initials: H
authors.lastname: Hernandez
authors.forename: J
authors.initials: J
authors.lastname: Elzo
authors.forename: D
authors.initials: D
authors.lastname: Moraga
mesh_terms: D002946:Cisterna Magna / Q000098:blood supply / Q000473:pathology* / Q000601:surgery; D006801:Humans; D006849:Hydrocephalus / Q000150:complications / Q000473:pathology* / Q000601:surgery; D020547:Lateral Ventricles / Q000098:blood supply / Q000473:pathology* / Q000601:surgery; D008591:Meningomyelocele / Q000150:complications / Q000473:pathology* / Q000601:surgery; D044583:Neuroendoscopy; D020542:Third Ventricle / Q000098:blood supply / Q000473:pathology* / Q000601:surgery; D014696:Ventriculostomy; D014741:Video Recording