Role of extensible physics engine in surgery simulations

Surgery simulations are of significant value in medical training as they provide a less costly mean of training new surgeons. The quality of a surgery simulation is defined by how realistic it is in a physical sense. These physics aspects however have little to do the high-level functionalities of the application. Most VR (virtual reality) applications use libraries called physics engine for enforcing physics laws in their virtual worlds. Although the concept of using physics engines is ideal for development of VR applications, in practice it does impose many limitations. For instance, there are many physical laws in the world, and one single physics engine cannot provide all of them. In addition, each physical law can be implemented differently; some are optimized for fast response, others are designed for maximum precision. Most existing physics engines are specialized for common applications such as gaming, robotic or flight simulations. In surgery applications, the requirements are different; therefore different physics laws are needed. In particular, laws are needed for simulating cutting and skin deformation. In addition, these laws must be enforced with a high precision level. We discuss how xPheve was used to develop a cataract eye surgery simulation. xPheve is a physics engine that allows extension and customization of the simulation physics through development and integration of reusable law components. This work discusses how xPheve can benefit the development of the surgery simulations.