title: Quantitative ventricular neuroendoscopy performed on the third ventriculostomy: anatomic study.
abstract: BACKGROUND
  One of the key elements for a successful endoscopic intervention in the ventricular system is the ability to recognize the anatomic structures and use them as a reference.
  
  
  OBJECTIVE
  To measure the choroid plexus with endoscopy in the interventricular foramen, together with the structures on the third ventricle floor, and to compare these variables.
  
  
  METHODS
  An observational prospective study was carried out on 37 brains of cadavers for which the cause of death was assessed at the Death Check Unit of the University of São Paulo in April 2008. This study was done on adults of both sexes with a rigid neuroendoscope. Endoscopic images were recorded, submitted for correction of distortion, and then measured.
  
  
  RESULTS
  The measurements of the choroid plexus in the interventricular foramen, laterolateral distance of mammillary bodies, distance from the infundibular recess to the mammillary bodies, and area of the triangle in the tuber cinereum were 1.71 ± 0.77 mm, 2.23 ± 0.74 mm, 3.22 ± 0.82 mm, and 3.69 ± 2.09 mm, respectively. The ventricle floor was opaque in 84% of cases. The internal distance of mammillary bodies was absent in 89%. Associations between the translucent floor of the third ventricle and laterolateral distance of mammillary bodies, internal distance of mammillary bodies, and age were identified.
  
  
  CONCLUSIONS
  Before this research, there was no record of the measurements of the choroid plexus in the interventricular foramen. The remaining variables of the present study show a greater number in normal brains compared with others.
authors.affiliation: Department of Neurology, Division of Neurosurgery, Hospital das Clínicas, University of São Paulo, São Paulo, SP, Brazil. alicia21221@hotmail.com
authors.forename: Alicia Del Carmen Becerra
authors.initials: Adel C
authors.lastname: Romero
authors.forename: Paulo Henrique Pires de
authors.initials: PH
authors.lastname: Aguiar
authors.forename: Tiago Bonini
authors.initials: TB
authors.lastname: Borchartt
authors.forename: Aura
authors.initials: A
authors.lastname: Conci
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D002831:Choroid Plexus / Q000033:anatomy & histology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D044583:Neuroendoscopy; D020542:Third Ventricle / Q000033:anatomy & histology* / Q000601:surgery*; D014696:Ventriculostomy / Q000379:methods*