1. Ying Li, Ken Brodlie and Nicholas Phillips * School of Computer Studies, University of Leeds, UK http://www.scs.leeds.ac.uk/vis/ ying / Web-based VR Training Simulator for Percutaneous Rhizotomy January 29, 2000 * Department of Neurosurgery, Leeds General Infirmary, UK

2. Contents Motivation Surgical procedure The simulator Conclusions

3. Motivation The limitation of current VR training systems The advantages of web based VR environment It is possible Dedicated, expensive equipment Accessible, scalable, low cost

4. The Surgical Procedure - Percutaneous Rhizotomy Lesion Generator Insert needle electrode at correct position & orientation on face Locate & puncture foramen ovale to access and burn ganglion nerve

5. Highly skilled operation Why is Simulation Useful Risky Awkward to train new staff Especially to locate foramen ovale Patient awake for part of the procedure Dissection of carotid artery will affect blood supply to brain

6. A simple web-based simulator Our Simulator Aims to be an adjunct to training of neurosurgeons Shorten period of training Understanding of procedure and risks involved

7. VRML world extended with Java EAI to provide simulation The Simulator - Architecture Client-based system Download self-contained simulation to client Web Server Browser download Single download, no dependency on network

8. Extend reality by multiple views The Simulator - Virtual World From the eye of the surgeon From the eye of the needle electrode Eye of the surgeonEye of the needle Java EAI

9. Virtual planes Place landmarks The Simulator - Simulating The Surgical Practice

10. The Simulator - Manipulating The Tools Controller Rotate and translate according to rules of surgical procedure Three VRML worlds co-ordinated through Java EAI

11. The Simulator - Hitting The Target Collision detection between Only collision with viewer objects not supported in VRML Solution: Detect collision with eye of the needle electrode

12. Success

13. Oops….

14. Client-based WWW surgical training system is fast, cheap, … Collision detection between needle and multiple complex objects is efficient Conclusion Various surgical tasks have been simulated Complexity versus ease of use ?