A. C. F Colchester, R. L. Evans, J. Zhao, D. J. Hawkes, C. Studholme, D. L. G. Hill, P. Roberts, M. Stephens, N. Maitland, A. J. Strong, M. J. Gleeson, D. G. Thomas, and T. C. S. Cox
In order to approach his target safely and accurately a surgeon needs to relate information derived from preoperative images to the live patient in theatre, and he also needs to integrate intra-operative imaging information (video, ultrasound etc) to update his surgical plan. We are developing a novel frameless stereotactic system (P'/$LAN) which uses v~ible landmarks, for registering data obtained pre-operatively (the pre-operative patient representation or POPR) to data obtained from stereo video imaging in theatre (the intra-operative patient representation or IOPR). An important component of the system is a hand-held pointing device (locater), without mechanical electrical linkages, which can be tracked by the stereo video system.