title: Accessible laparoscopic instrument tracking ("InsTrac"): construct validity in a take-home box simulator.
abstract: BACKGROUND
  Objective performance feedback has potential to maximize the training benefit of laparoscopic simulators. Instrument movement metrics are, however, currently the preserve of complex and expensive systems. We aimed to develop and validate affordable, user-ready software that provides objective feedback by tracking instrument movement in a "take-home" laparoscopic simulator.
  
  
  METHODS
  Computer-vision processing tracks the movement of colored bands placed around the distal instrument shafts. The position of each instrument is logged from the simulator camera feed and movement metrics calculated in real time. Ten novices (junior doctors) and 13 general surgery trainees (StR) (training years 3-7) performed a standardized task (threading string through hoops) on the eoSim (eoSurgical™ Ltd., Edinburgh, Scotland, United Kingdom) take-home laparoscopic simulator. Statistical analysis was performed using unpaired t tests with Welch's correction.
  
  
  RESULTS
  The software was able to track the instrument tips reliably and effectively. Significant differences between the two groups were observed in time to complete task (StR versus novice, 2 minutes 33 seconds versus 9 minutes 53 seconds; P=.01), total distance traveled by instruments (3.29 m versus 11.38 m, respectively; P=.01), average instrument motion smoothness (0.15 mm/second(3) versus 0.06 mm/second(3), respectively; P<.01), and handedness (mean difference between dominant and nondominant hand) (0.55 m versus 2.43 m, respectively; P=.03). There was no significant difference seen in the distance between instrument tips, acceleration, speed of instruments, or time off-screen.
  
  
  CONCLUSIONS
  We have developed software that brings objective performance feedback to the portable laparoscopic box simulator. Construct validity has been demonstrated. Removing the need for additional motion-tracking hardware makes it affordable and accessible. It is user-ready and has the potential to enhance the training benefit of portable simulators both in the workplace and at home.
authors: 1 Royal Hospital for Sick Children , Edinburgh, Scotland, United Kingdom .
authors: Roland W
authors: RW
authors: Partridge
authors: Mark A
authors: MA
authors: Hughes
authors: Paul M
authors: PM
authors: Brennan
authors: Iain A M
authors: IA
authors: Hennessey
mesh_terms: D001185:Artificial Intelligence / Q000592:standards*; D003198:Computer Simulation / Q000592:standards*; D006801:Humans; D010535:Laparoscopy / Q000193:education* / Q000379:methods*; D012984:Software; D013647:Task Performance and Analysis; D006113:United Kingdom