title: An experimental comparison of 3-dimensional and 2-dimensional endoscopic systems in a model.
abstract: OBJECTIVE
  This study compares the effect of new electronic display systems using endoscopic instruments on intrathoracal maneuvering and targeting under standardized conditions. A 2-dimensional (2-D) vision system is compared with 2 stereoscopic 3-dimensional (3-D) video technologies, called "shutter glasses," and the head-mounted display (HMD) system.
  
  
  METHODS
  Fifteen participants with minor experience (<50 operations = beginners) and 15 participants with endoscopic experience (advanced) had to hit 12 electronically conducted wires in a thoracic spine model using 3 different systems (2-D video, 3-D shutter glasses, and 3-D HMD). The sequence was randomly alternated for each participant and repeated 3 times to eliminate the influence of training and concentration.
  
  
  RESULTS
  The execution time with the 2-D system (mean time, 95.5 seconds) was shorter than with the HMD (mean time, 107 seconds; P =.001) or the Shutter system (mean time, 101 seconds; P =.002). No significant difference was seen between the 3-D systems (P =.153). The overall look of the missed targets showed statistically no difference between the 3 systems (P =.191). None of the 3 systems showed a statistically significant correlation between execution time and number of missed targets. Regarding the total number of missed targets for advanced and beginner groups, the head-mounted display system in the advanced group showed higher but not statistically significantly higher accuracy.
  
  
  CONCLUSIONS
  Although the 3-D systems tested for endoscopic surgery did not accelerate the execution speed, the HMD system seems to increase the accuracy for endoscopically experienced surgeons.
authors.affiliation: Orthopedic Surgery Hospital, University of Heidelberg, Heidelberg, Germany. marc.thomsen@ok.uni-heidelberg.de
authors.forename: Marc N
authors.initials: MN
authors.lastname: Thomsen
authors.forename: Robert D
authors.initials: RD
authors.lastname: Lang
mesh_terms: D002983:Clinical Competence; D003626:Data Display; D003867:Depth Perception; D004724:Endoscopy; D004867:Equipment Design; D005139:Eyeglasses; D006801:Humans; D021621:Imaging, Three-Dimensional; D007858:Learning; D008328:Man-Machine Systems; D008953:Models, Anatomic; D009985:Orthopedics / Q000379:methods*; D010820:Physicians / Q000523:psychology; D011897:Random Allocation; D013904:Thoracic Vertebrae; D013997:Time Factors; D014584:User-Computer Interface; D020535:Video-Assisted Surgery / Q000295:instrumentation*