Objective
To develop a virtual Reality (VR) simulator to teach the various mechanisms through which injury can occur when using electrosurgery during minimally invasive surgery.
Description and Methods
Inadvertent thermal injuries do occasionally occur when using electrosurgical devices. The 3 main mechanisms responsible are insulation failure, direct coupling and capacitive coupling. A force feedback enabled VR simulator was built to highlight the above three mechanisms to train residents and surgeons in safe usage of electrosurgery. The simulator consists of three textured rigid objects (two spheres and one cube in this case). A virtual grasper and a foot activated monopolar electrosurgical tool was used to interact with the virtual models. Two PHANToM Omni™ devices were used to manipulate the tools and provide force feedback to the users. When the user performs electrosurgery by cauterizing the surface of the three virtual objects, real-time spark, smoke and charring effects provided enhancement.
The VR electrosurgery simulator consists of four modules (Figure 1). The first is the ‘no failure’ module in which the users can interact with the models and perform electrosurgery. In the ‘insulation failure’ module, a small insulation defect was created in the tool and represented as a colored sphere. When the defect is in close proximity to the rigid objects, the surface closest to the defect is burnt illustrating the insulation failure effect. In the ‘direct coupling’ module, whenever the electrosurgery tool comes in contact with the grasper with its tip in close proximity to the rigid objects, the surface of the closest object is burnt. In the ‘capacitive coupling’ module, as the user cauterizes the surface of the rigid objects, the proximity of the cannula to the upper surface where the virtual trocar is inserted was calculated and smoke effect was created when the distance was very small to illustrate the discharge of energy through capacitive coupling.
Results
This VR simulator was piloted by electrosurgical experts at a recent meeting. Overall, the experts agreed that the simulator has great potential for teaching electrosurgery and its potential complications.
Conclusions and Future Directions
Electrosurgery is the most commonly used surgical technique in MIS. Patient injury can occur during electrosurgery due to improper use of tools, techniques and defects. In this work, for the first time, an interactive VR simulator was developed to illustrate three major mechanisms through which injuries can occur while performing electrosurgery.
We plan to perform more rigorous validation studies of the simulator at the Beth Isarel Deconness Medical Center in Boston.
