title: Measurements of burr-hole localization for endoscopic procedures in the third ventricle in children.
abstract: OBJECTIVE
  In a retrospective study, we measured the localization for the burr hole for neuroendoscopic procedures in the third ventricle, which are determined by anatomical landmarks like the foramen of Monro (FM) and the respective targets.
  
  
  METHODS
  In 48 children, thin-sliced T2-weighted magnetic resonance images were analyzed within an imaging software tool to determine the trajectory between the FM to the floor of the third ventricle (F3V) or the entrance of the sylvian aqueduct (SA). The crossing point at the skull convexity defined the entry points. Coordinates are given relative to nasion and midline. A mean virtual entry point to reach both targets was compared to the burr-hole localization used in the respective surgeries. The tissue shift at the FM was quantified for the trajectories.
  
  
  RESULTS
  The entry point to reach the F3V or the SA measured 119.7+/-26.4 mm (to nasion)-20.5+/-11.5 mm (to midline) and 57.4+/-26.5-18.8+/-8.3 mm, respectively. The virtual mean entry point to reach both targets was located at 86.5+/-25.3-20.9+/-9.8 mm. There was a statistical difference in the entry point localization relative to nasion of the virtual mean trajectory compared with the burr-hole localization used in these patients. The tissue shift at the level of the FM using the mean virtual trajectory was significantly lower than by using the actual burr hole to the SA.
  
  
  CONCLUSIONS
  Planning an optimal burr-hole localization is important in neuroendoscopic procedures in children, especially where the target is located around the sylvian aqueduct.
authors.affiliation: Selbständiger Arbeitsbereich für Pädiatrische Neurochirurgie, Charité, Campus Virchow Klinikum, Universitätsmedizin zu Berlin, Augustenburger Platz 1, 13353 Berlin, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Knaus
authors.forename: A
authors.initials: A
authors.lastname: Abbushi
authors.forename: K T
authors.initials: KT
authors.lastname: Hoffmann
authors.forename: K
authors.initials: K
authors.lastname: Schwarz
authors.forename: H
authors.initials: H
authors.lastname: Haberl
authors.forename: U W
authors.initials: UW
authors.lastname: Thomale
mesh_terms: D000293:Adolescent; D002535:Cerebral Aqueduct / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D006849:Hydrocephalus / Q000175:diagnosis / Q000601:surgery*; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D008297:Male; D044583:Neuroendoscopy; D019635:Neurosurgical Procedures / Q000379:methods*; D012189:Retrospective Studies; D012886:Skull / Q000473:pathology* / Q000601:surgery; D013238:Stereotaxic Techniques; D020542:Third Ventricle / Q000473:pathology* / Q000601:surgery