Previous Projects

A mass-spring adaptive deformable model for surgical simulation

This project addressed the problem of graphically modelling and animating at interactive frame rates the realistic behaviour of deformable materials that can undergo structural modifications. The methodology was applied to the interactive simulation of minimally-invasive surgery. Based on a volumetric mass-spring system, three-dimensional volumes were modelled using a mesh of tetrahedral elements and physically deformed under the effect of external and internal forces. Unlike traditional surface representations, a correct deformation behaviour of the system was achieved by modelling its interior, and therefore implicitly connecting its opposite sides. In order to optimally distribute the computational workload, the system adapts the resolution of tetrahedra by dynamically re-tessellating the mesh in and around the regions of interest. The parameters are assigned so that the system stays self-consistent despite changes of resolution. System stability and real-time simulation are guaranteed by dynamically adapting and controlling the numerical integration. This technique overcomes limitations of previous methods that made it dificult to modify the topology of the mesh on-line. Applications were presented to demonstrate that this method can be used to achieve real time soft tissue deformation in surgical simulation and allows the simulation of surgical procedures entailing the modification of tissue structure.

WebSET – Web-based Standard Educational Tools

Medical education has traditionally relied on direct patient contact and dedicated instructors. Learners have little opportunity to learn and practice clinical skills without jeopardizing patient safety. Over the past decade rapid and significant advances in computing technology have offered a number of alternatives to this conventional model of learning. Learning opportunities have been shown to be enhanced by Computer Assisted learning (CAL) and virtual reality. There have been a number of studies emphasizing the role of multimedia based training. In contrast to the instructional and interactive nature of multi-media packages, VR technology makes the learning process more ‘hands-on’ and permits the acquisition of skills essential for the successful performance of a procedure. VR has the potential to address many of the inherent problems associated with a patient based approach to learning. VR simulators have been developed for endoscopy and laparoscopic surgery which help the novice to acquire and practice skills unique to these. Further progress has resulted in the integration of CAL and VR to the World Wide Web. The WebSET project is a significant step in a similar direction. The educational tool was developed with the objective of making re-usable multimedia material consisting of high quality courseware, self-assessment exercises and video clips with VR simulation available on the Internet. The project used advanced Web-based technologies to implement innovative cost-effective learning tools that could be run on any workstation platform including a standard desktop PC of average specifications. This technology goes a step further than the philosophy of ‘medical education on demand’ and makes learning available ‘anytime and anywhere’. The tool is easily accessible to students either on an institutional server or while they are at home. It brings an interactive ‘virtual classroom’ into the homes of medical students.