title: Comparative effectiveness and safety of image guidance systems in neurosurgery: a preclinical randomized study.
abstract: OBJECTIVE
  Over the last decade, image guidance systems have been widely adopted in neurosurgery. Nonetheless, the evidence supporting the use of these systems in surgery remains limited. The aim of this study was to compare simultaneously the effectiveness and safety of various image guidance systems against that of standard surgery.
  
  
  METHODS
  In this preclinical, randomized study, 50 novice surgeons were allocated to one of the following groups: 1) no image guidance, 2) triplanar display, 3) always-on solid overlay, 4) always-on wire mesh overlay, and 5) on-demand inverse realism overlay. Each participant was asked to identify a basilar tip aneurysm in a validated model head. The primary outcomes were time to task completion (in seconds) and tool path length (in mm). The secondary outcomes were recognition of an unexpected finding (i.e., a surgical clip) and subjective depth perception using a Likert scale.
  
  
  RESULTS
  The time to task completion and tool path length were significantly lower when using any form of image guidance compared with no image guidance (p < 0.001 and p = 0.003, respectively). The tool path distance was also lower in groups using augmented reality compared with triplanar display (p = 0.010). Always-on solid overlay resulted in the greatest inattentional blindness (20% recognition of unexpected finding). Wire mesh and on-demand overlays mitigated, but did not negate, inattentional blindness and were comparable to triplanar display (40% recognition of unexpected finding in all groups). Wire mesh and inverse realism overlays also resulted in better subjective depth perception than always-on solid overlay (p = 0.031 and p = 0.008, respectively).
  
  
  CONCLUSIONS
  New augmented reality platforms may improve performance in less-experienced surgeons. However, all image display modalities, including existing triplanar displays, carry a risk of inattentional blindness.
authors.affiliation: The Hamlyn Centre for Robotic Surgery, Institute of Global Health Innovation, and.|Department of Neurosurgery, Imperial College Healthcare NHS Trust, London, United Kingdom.
authors.forename: Hani J
authors.initials: HJ
authors.lastname: Marcus
authors.affiliation: The Hamlyn Centre for Robotic Surgery, Institute of Global Health Innovation, and.
authors.forename: Philip
authors.initials: P
authors.lastname: Pratt
authors.affiliation: The Hamlyn Centre for Robotic Surgery, Institute of Global Health Innovation, and.
authors.forename: Archie
authors.initials: A
authors.lastname: Hughes-Hallett
authors.affiliation: The Hamlyn Centre for Robotic Surgery, Institute of Global Health Innovation, and.
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Cundy
authors.affiliation: Faculty of Medicine, Imperial College London, United Kingdom; and.
authors.forename: Adam P
authors.initials: AP
authors.lastname: Marcus
authors.affiliation: The Hamlyn Centre for Robotic Surgery, Institute of Global Health Innovation, and.
authors.forename: Guang-Zhong
authors.initials: GZ
authors.lastname: Yang
authors.affiliation: The Hamlyn Centre for Robotic Surgery, Institute of Global Health Innovation, and.
authors.forename: Ara
authors.initials: A
authors.lastname: Darzi
authors.affiliation: Department of Neurosurgery, Imperial College Healthcare NHS Trust, London, United Kingdom.
authors.forename: Dipankar
authors.initials: D
authors.lastname: Nandi
mesh_terms: D001921:Brain / Q000601:surgery*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000295:instrumentation / Q000379:methods*; D019635:Neurosurgical Procedures / Q000295:instrumentation / Q000379:methods*; D025321:Surgery, Computer-Assisted / Q000295:instrumentation / Q000379:methods*
keywords: MARTYN = Modelled Anatomical Replica for Training Young Neurosurgeons; augmented reality; diagnostic and operative techniques; image guidance; minimally invasive surgery; neurosurgery