Magnetically Anchored Cautery Dissector Improves Triangulation, Depth Perception, and Workload During Single-Site Laparoscopic Cholecystectomy

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This study evaluated operative outcomes and workload during single-site laparoscopy (SSL) using a magnetically anchored cautery dissector (MAGS) compared with a conventional laparoscopic hook cautery (LAP).


Each cautery was used to perform six SSL porcine cholecystectomies. For MAGS, the cautery device was inserted through the umbilical incision, magnetically coupled, and deployed; two graspers and a laparoscope were used. For LAP, two percutaneous retraction sutures, one grasper, a hook cautery dissector, and a laparoscope were used. Operative outcomes, surgeon ratings (scale, 1–5; 1 = superior), and workload (scale, 1–10; 1 = superior) were evaluated.


No significant differences were detected for operative outcomes and surgeon ratings, however, trends were detected favoring MAGS. Surgeon workload ratings were significantly better for MAGS (2.6 ± 0.2) vs. LAP (5.6 ± 1.1; p < 0.05). For MAGS, depth perception and triangulation were excellent and the safe handling protocol was followed with no complications. For LAP, the parallelism of instruments and lack of triangulation hindered depth perception, caused instrument conflicts, and resulted in two minor complications (one superficial liver laceration and one inadvertent burn to the diaphragm).


These data suggest that using the MAGS device for SSL cholecystectomy results in equivalent (or better) operative outcomes and less workload compared with LAP.

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We would like to acknowledge the generous contributions in research grants that were provided for this study by Ethicon Endo-Surgery, Inc. (Cincinnati, OH).


These devices are not approved by the Food and Drug Administration (FDA) for use in humans and are intended for research and experimental purposes only at this time.

Author information

Correspondence to Daniel J. Scott.

Additional information

For consideration in the Journal of Gastrointestinal Surgery

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Arain, N.A., Cadeddu, J.A., Hogg, D.C. et al. Magnetically Anchored Cautery Dissector Improves Triangulation, Depth Perception, and Workload During Single-Site Laparoscopic Cholecystectomy. J Gastrointest Surg 16, 1807–1813 (2012).

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  • Magnetic anchoring and guidance system (MAGS)
  • Magnetic instruments
  • Single-site laparoscopy (SSL)
  • Triangulation
  • Workload