title: Human vs robotic organ retraction during laparoscopic Nissen fundoplication.
abstract: BACKGROUND
  Advances in technique and instrumentation have enabled surgeons to perform an increasing number of complicated procedures through laparoscopy. However, these efforts have often been compromised by the exertion of excessive force when anatomical structures are retracted to create a clear view of the anatomy. Here, we present a comparative study of human and robotic performance in force-controlled organ retraction during laparoscopic Nissen fundoplication (LNF).
  
  
  METHODS
  Six female pigs (20-25 kg) were anesthetized, intubated, and placed on mechanical ventilation; pneumoperitoneum (13 mmHg CO2) was established. A force-sensing retractor (FSR) was constructed to record the forces applied in retracting the stomach during dissection of the esophageal hiatus. The FSR was calibrated using known forces and then operated by either human alone or robot under human guidance using the FSR data. The esophageal hiatus was visualized and dissected, and LNF was completed.
  
  
  RESULTS
  Less force was needed for robotic (74.3 +/- 10.5 g; mean +/- standard deviation) than for human (108.9 +/- 34.3 g) retraction (p = 0.007) to obtain an optimal view of the esophageal hiatus. No significant differences were observed for retraction setup time (robot, 14.3 +/- 0.8 min; human, 13.7 +/- 9.9 min; mean +/- SD) or hiatal dissection time (robot, 14.0 +/- 3.0 min; human, 14.0 +/- 6.1 min; mean +/- SD).
  
  
  CONCLUSIONS
  These preliminary results illustrate our continuing effort to develop and evaluate an automated surgical assistant for laparoscopy. As more personnel-intensive advanced laparoscopic procedures are performed, robotic retraction is likely to offer a superior alternative to human retraction; it minimizes the forces exerted on the organs while maintaining excellent anatomical view.
authors.affiliation: Department of Surgery, Johns Hopkins University School of Medicine, Blalock 665, 600 North Wolfe Street, Baltimore, MD 21287, USA.
authors.forename: B K
authors.initials: BK
authors.lastname: Poulose
authors.forename: M F
authors.initials: MF
authors.lastname: Kutka
authors.forename: M
authors.initials: M
authors.lastname: Mendoza-Sagaon
authors.forename: A C
authors.initials: AC
authors.lastname: Barnes
authors.forename: C
authors.initials: C
authors.lastname: Yang
authors.forename: R H
authors.initials: RH
authors.lastname: Taylor
authors.forename: M A
authors.initials: MA
authors.lastname: Talamini
mesh_terms: D000818:Animals; D004867:Equipment Design; D005260:Female; D018662:Fundoplication / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D020706:Laparoscopes; D012371:Robotics; D013552:Swine