title: Optimization of ventricular catheter placement via posterior approaches: a virtual reality simulation study.
abstract: BACKGROUND
  This study aimed to evaluate 2 commonly used posterior approach entry points for ventricular cannulation and the ideal trajectories using 3-dimensional virtual reality technology.
  
  
  METHODS
  Magnetic resonance imaging data of 10 patients without gross ventricular dilatation or distortion were retrieved and reconstructed. A stereoscopic 3-dimensional preoperative planning system was used to designate the entry points. Various trajectories were simulated. The ideal trajectory was determined as the one that provided direct entry into the atrium or body of the lateral ventricle en route to the ipsilateral frontal horn.
  
  
  RESULTS
  Magnetic resonance imaging data sets from 10 patients were used. For the entry point 6 cm above and 4 cm lateral to the inion (Frazier's point), ideal cannulation was achieved for all 10 patients when the selected target was 4 cm above the contralateral medial canthus. When the contralateral medial canthus was targeted, 5 patients had successful outcomes. There were only 3 satisfactory outcomes each when the ipsilateral medial canthus and glabella were targeted. The target 2 cm above the glabella yielded 2 satisfactory outcomes. The entry point 3 cm above and 2 cm lateral to the inion (Dandy's point) had 10 satisfactory outcomes when the target point was 2 cm above the glabella. All the other target points, namely, ipsilateral medial canthus, contralateral medial canthus, 4 cm above the contralateral medial canthus and glabella yielded poor results.
  
  
  CONCLUSIONS
  For satisfactory placement when entering via Frazier's point, the best trajectory target would be 4 cm above the contralateral medial canthus. When entering via Dandy's point, the best target would be 2 cm above the glabella.
authors.affiliation: Department of Neurosurgery, National Neuroscience Institute, 308433, Singapore. chengkiang.lee@gmail.com
authors.forename: Cheng Kiang
authors.initials: CK
authors.lastname: Lee
authors.forename: Lee Lian
authors.initials: LL
authors.lastname: Tay
authors.forename: Wai Hoe
authors.initials: WH
authors.lastname: Ng
authors.forename: Ivan
authors.initials: I
authors.lastname: Ng
authors.forename: Beng Ti
authors.initials: BT
authors.lastname: Ang
mesh_terms: D002404:Catheterization / Q000379:methods* / Q000592:standards; D002408:Catheters, Indwelling / Q000592:standards; D002552:Cerebral Ventricles / Q000033:anatomy & histology / Q000601:surgery*; D003399:Craniotomy / Q000379:methods; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007431:Intraoperative Complications / Q000517:prevention & control; D020547:Lateral Ventricles / Q000033:anatomy & histology / Q000601:surgery; D008279:Magnetic Resonance Imaging / Q000379:methods; D038361:Neuronavigation / Q000379:methods*; D011183:Postoperative Complications / Q000517:prevention & control; D011300:Preoperative Care / Q000379:methods*; D012886:Skull / Q000033:anatomy & histology / Q000601:surgery; D014584:User-Computer Interface; D014696:Ventriculostomy / Q000379:methods*