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Abstract Laparoscopic surgery has a notably high learning curve, hindering typical approaches to training. Due to unique challenges that are not present in open surgery (the hinge effect, small field of view (FoV), lack of depth perception, and small workspace), a surgical resident may be delayed in participating in laparoscopic surgery until later in residency. Having a narrow window to complete highly specialized training can lead to graduates feeling under-prepared for solo practice. Additionally, delayed introduction may expose trainees to fewer than 200 laparoscopic cases. Therefore, there is a need for surgical residents to increase both their caseload and training window without compromising patient safety. This project aims to develop and test a proof-of-concept prototype that uses granular jamming technology to controllably vary the force required to move a laparoscopic tool. By increasing tool resistance, the device helps prevents accidental injury to important nearby anatomical structures such as urinary tract, vasculature, and/or bowel. Increasing the safety of laparoscopic surgery would allow residents to begin their training earlier, gaining exposure and confidence. A device to adjust tool resistance has benefits to the experienced surgeon as well – surgeries require continuous tool adjustment and tension, resulting in fatigue. Increasing tool resistance can assist surgeons in situations requiring continuous tension and can also provide safety against sudden movements. This investigational device was prototyped using SolidWorks CAD software, then 3D printed and assessed with a laparoscopic box trainer.
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Training with a Visual-Haptic Simulator for Trocar Insertion
Trocar insertion is a critical first step of all minimally invasive surgery; however, it also carries a high risk for errors. Studies suggest that entry errors are the most common complication in laparoscopic surgery with 4% of errors leading to patient fatality. Surgeon error due to excessive force is often the cause for entry errors; however, adequate training has been shown to reduce the risk of these surgical errors. In practice, institutions lack widespread and relatively inexpensive means to train surgeons for trocar entry that does not involve patient risk. In our prior work, we presented a simple Stewart platform haptic device with a numerical model to simulate key force characteristics of trocar insertion. Evaluation in our first study was limited to device characterization. In this paper, we present a more robust haptic mechanism with higher fidelity linear actuators, an increased workspace, and tissue visualization to accompany haptic cues. We also present a novel upper module that allows for a sudden drop of the trocar after the final puncture event to create a more realistic simulation. We performed a user study with eight novices to investigate how well the device and visualization train users in the trocar insertion procedure. By the end of the experiment, subjects using the device had a normalized error reduction of roughly 85% on average, relative to themselves. This device shows potential for widespread training of trocar insertion, possibly leading to fewer complications and deaths following the procedure. Finally, our upper module also represents an innovative addition for traditional admittance-type haptic device designs, not typically capable of accurately representing motion in free space.
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- Award ID(s):
- 2109635
- PAR ID:
- 10550500
- Publisher / Repository:
- Journal of Medical Robotics Research
- Date Published:
- Journal Name:
- Journal of Medical Robotics Research
- ISSN:
- 2424-905X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1142/S2424905X24400075
