Surgical Endoscopy

, Volume 29, Issue 12, pp 3655–3665 | Cite as

Randomized control trial for evaluation of a hands-free pointer for surgical instruction during laparoscopic cholecystectomy

  • Ana Luisa Trejos
  • Karen Siroen
  • Christopher D. W. Ward
  • Shahan Hossain
  • Michael D. Naish
  • Rajni V. Patel
  • Christopher M. Schlachta



Training surgeons in minimally invasive surgery (MIS) requires surgical residents to operate under the direction of a consultant. The inability of the instructing surgeon to point at the laparoscopic monitor without releasing the instruments remains a barrier to effective instruction. The wireless hands-free surgical pointer (WHaSP) has been developed to aid instruction during MIS.


The objective of this study was to evaluate the effectiveness and likeability of the WHaSP as an instructional tool compared with the conventional methods. Data were successfully collected during 103 laparoscopic cholecystectomy procedures, which had been randomized to use or not use the WHaSP as a teaching tool. Audio and video from the surgeries were recorded and analyzed. Instructing surgeons, operating surgeons, and camera assistants provided feedback through a post-operative questionnaire that used a five-level Likert scale. The questionnaire results were analyzed using a Mann–Whitney U test.


There were no negative effects on surgery completion time or instruction practice due to the use of the WHaSP. The number of times an instructor surgeon pointed to the laparoscopic screen with their hand was significantly reduced when the WHaSP was utilized (p < 0.001). The questionnaires showed that WHaSP users found it to be comfortable, easy to use, and easy to control. Compared to when the WHaSP was not used, users found that communication was more effective (p = 0.002), locations were easier to communicate (p < 0.001), and instructions were easier to follow (p = 0.005).


The WHaSP system was successfully used in surgery. It integrated seamlessly into existing equipment within the operating room and did not affect flow. The positive outcomes of utilizing the WHaSP were improved communication in the OR, improved efficiency and safety of the surgery, easy to use, and comfortable to wear. The surgeons showed a preference for utilizing the WHaSP if given a choice.


Medical mechatronic systems Hands-free pointing Surgical instruction Instructing technology 



The authors would like to thank all of the vast number of surgeons and trainees who willingly participated in the trials, and the nurses and other support staff in the ORs at the London Health Sciences Centre University Hospital, Victoria Hospital, and St. Joseph’s Health Care. The authors also recognize the support from J.W. Gillies from Stryker for assisting with the integration of the WHaSP with the equipment in the OR and Dr. Nawar Alkhamesi for his assistance during the early stages of the evaluation. This work was supported in part by grants from the Western Innovation Fund and the C4 Consortium (R.V. Patel), in part by the Physicians Services Incorporated (PSI) Foundation (C.M. Schlachta), in part by the Natural Sciences and Engineering Research Council (NSERC) of Canada under Grant I2IPJ403191-10, and in part by infrastructure grants from the Canada Foundation for Innovation awarded to the London Health Sciences Centre [Canadian Surgical Technologies and Advanced Robotics (CSTAR)], and to the University of Western Ontario (UWO) (R. V. Patel).


Christopher M. Schlachta, Rajni V. Patel, Ana Luisa Trejos, and Michael D. Naish are inventors and have a patent application for the WHaSP. The results presented in this article are not part of the patent application. Christopher M. Schlachta, Rajni V. Patel, Ana Luisa Trejos, Michael D. Naish and Christopher D.W. Ward are planning to incorporate a company for the purpose of licensing the WHaSP system. They have no other conflicts of interest and no financial ties to disclose. Karen Siroen, and Shahan Hossain have no conflicts of interest or financial ties to disclose.


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Ana Luisa Trejos
    • 1
    • 2
  • Karen Siroen
    • 2
  • Christopher D. W. Ward
    • 2
  • Shahan Hossain
    • 3
  • Michael D. Naish
    • 2
    • 4
  • Rajni V. Patel
    • 2
    • 5
  • Christopher M. Schlachta
    • 2
    • 3
  1. 1.Department of Electrical and Computer EngineeringUniversity of Western OntarioLondonCanada
  2. 2.Canadian Surgical Technologies and Advanced RoboticsLawson Health Research InstituteLondonCanada
  3. 3.Department of Surgery, Schulich School of Medicine and DentistryThe University of Western OntarioLondonCanada
  4. 4.Department of Mechanical and Materials Engineering and Department of Electrical and Computer EngineeringThe University of Western OntarioLondonCanada
  5. 5.Department of Electrical and Computer Engineering and Department of SurgeryUniversity of Western OntarioLondonCanada

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