title: Virtual interactive presence and augmented reality (VIPAR) for remote surgical assistance.
abstract: BACKGROUND
  Surgery is a highly technical field that combines continuous decision-making with the coordination of spatiovisual tasks.
  
  
  OBJECTIVE
  We designed a virtual interactive presence and augmented reality (VIPAR) platform that allows a remote surgeon to deliver real-time virtual assistance to a local surgeon, over a standard Internet connection.
  
  
  METHODS
  The VIPAR system consisted of a "local" and a "remote" station, each situated over a surgical field and a blue screen, respectively. Each station was equipped with a digital viewpiece, composed of 2 cameras for stereoscopic capture, and a high-definition viewer displaying a virtual field. The virtual field was created by digitally compositing selected elements within the remote field into the local field. The viewpieces were controlled by workstations mutually connected by the Internet, allowing virtual remote interaction in real time. Digital renderings derived from volumetric MRI were added to the virtual field to augment the surgeon's reality. For demonstration, a fixed-formalin cadaver head and neck were obtained, and a carotid endarterectomy (CEA) and pterional craniotomy were performed under the VIPAR system.
  
  
  RESULTS
  The VIPAR system allowed for real-time, virtual interaction between a local (resident) and remote (attending) surgeon. In both carotid and pterional dissections, major anatomic structures were visualized and identified. Virtual interaction permitted remote instruction for the local surgeon, and MRI augmentation provided spatial guidance to both surgeons. Camera resolution, color contrast, time lag, and depth perception were identified as technical issues requiring further optimization.
  
  
  CONCLUSIONS
  Virtual interactive presence and augmented reality provide a novel platform for remote surgical assistance, with multiple applications in surgical training and remote expert assistance.
authors.affiliation: Division of Neurosurgery, Department of Surgery, University of Alabama-Birmingham, Alabama 35294-3410, USA.
authors.forename: Mahesh B
authors.initials: MB
authors.lastname: Shenai
authors.forename: Marcus
authors.initials: M
authors.lastname: Dillavou
authors.forename: Corey
authors.initials: C
authors.lastname: Shum
authors.forename: Douglas
authors.initials: D
authors.lastname: Ross
authors.forename: Richard S
authors.initials: RS
authors.lastname: Tubbs
authors.forename: Alan
authors.initials: A
authors.lastname: Shih
authors.forename: Barton L
authors.initials: BL
authors.lastname: Guthrie
mesh_terms: D002102:Cadaver; D003198:Computer Simulation; D003399:Craniotomy / Q000193:education / Q000295:instrumentation* / Q000379:methods*; D016894:Endarterectomy, Carotid / Q000193:education / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D012371:Robotics / Q000193:education / Q000295:instrumentation / Q000379:methods*; D012984:Software; D013238:Stereotaxic Techniques; D014584:User-Computer Interface