title: Mono-stereo-autostereo:  the evolution of 3-dimensional neurosurgical planning.
abstract: BACKGROUND
  In the past decade, surgery planning has changed significantly. The main reason is the improvements in computer graphical rendering power and display technology, which turned the plain graphics of the mid-1990s into interactive stereoscopic objects.
  
  
  OBJECTIVE
  To report our experiences with 2 virtual reality systems used for planning neurosurgical operations.
  
  
  METHODS
  A series of 208 operations were planned with the Dextroscope (Bracco AMT, Singapore) requiring the use of liquid crystal display shutter glasses. The participating neurosurgeons answered a questionnaire after the planning procedure and postoperatively. In a second prospective series of 33 patients, we used an autostereoscopic monitor system (MD20-3-D; Setred SA, Sweden) to plan intracranial operations. A questionnaire regarding the value of surgery planning was answered preoperatively and postoperatively.
  
  
  RESULTS
  The Dextroscope could be integrated into daily surgical routine. Surgeons regarded their understanding of the pathoanatomical situation as improved, leading to enhanced intraoperative orientation and confidence compared with conventional planning. The autostereoscopic Setred system was regarded as helpful in establishing the surgical strategy and analyzing the pathoanatomical situation compared with conventional planning. Both systems were perceived as a backup in case of failure of the standard navigation system.
  
  
  CONCLUSIONS
  Improvement of display and interaction techniques adds to the realism of the planning process and enables precise structural understanding preoperatively. This minimizes intraoperative guesswork and exploratory dissection. Autostereoscopic display techniques will further increase the value and acceptance of 3-dimensional planning and intraoperative navigation.
authors.affiliation: Neurochirurgische Klinik, Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Mainz, Germany. Axel.Stadie@me.com
authors.forename: Axel T
authors.initials: AT
authors.lastname: Stadie
authors.forename: Ralf A
authors.initials: RA
authors.lastname: Kockro
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001039:Aphasia, Broca / Q000601:surgery; D001932:Brain Neoplasms / Q000601:surgery*; D002533:Cerebral Angiography / Q000295:instrumentation / Q000379:methods; D005139:Eyeglasses; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000295:instrumentation / Q000379:methods*; D050866:Liquid Crystals; D018810:Magnetic Resonance Angiography / Q000295:instrumentation / Q000379:methods; D008297:Male; D008875:Middle Aged; D038361:Neuronavigation / Q000295:instrumentation / Q000379:methods*; D019635:Neurosurgical Procedures / Q000295:instrumentation / Q000379:methods*; D010243:Paralysis / Q000601:surgery; D010291:Paresis / Q000601:surgery; D011300:Preoperative Care / Q000295:instrumentation / Q000379:methods*; D011446:Prospective Studies; D014584:User-Computer Interface