Pilot Evaluation Study of a Virtual Paracentesis Simulator for Skill Training and Assessment: The Beneficial Effect of Haptic Display

Effective, real time training of health-care professionals in invasive procedures is a challenging task. Furthermore, assessing in practice the acquisition of the dexterity and skills required to safely perform such operations is particularly difficult to perform objectively and reliably. The development of virtual reality (VR) simulators offers great potential towards these objectives, and can help bypass some of the difficulties associated with classical surgical training and assessment procedures. In this context, we have developed a prototype VR simulator platform for training in a class of invasive procedures, such as accessing central vessels. This paper focuses more particularly on a pilot study treating the specific application case of subclavian vein paracentesis. The simulation incorporates 3D models of all the human anatomy structures involved in this procedure, where collision detection and response algorithms are implemented to simulate most of the potential complications in accordance to the situations encountered in real clinical practice. Furthermore, haptic display is integrated using a typical force feedback device providing the user with a sense of touch during the simulated operations. Our main objective in this study was to obtain quantitative evaluation results regarding the effect of haptic display on performance. Two user groups participated in the study: (I) novice users and (II) experienced surgeons. The system automatically provides quantitative assessment scores of users’ performance, applying a set of objective measures that also involve optimality of needle insertion path and indicators of maneuvering errors. Training and skill assessment performance of the system is evaluated in a twofold manner, regarding respectively: (a) the learning curve of novice users, and (b) the correlation of the system-generated scores with the actual surgical experience of the user. These performance indicators are assessed with respect to the activation of haptic display and to whether this has any beneficial effect (or not). The experimental findings of this first pilot study provide quantitative evidence about the significance of haptic display, not only as a means to enhance the realism of the surgical simulation, but especially as an irreplaceable component for achieving objective and reliable skill assessment. Further larger-scale and long-term clinical studies are needed to validate the effectiveness of such platforms for actual training and dexterity enhancement, particularly when more complex sensorimotor skills are involved.