Realtime transfer of live video images in parallel with three-dimensional modelling of the surgical field in computer-assisted telesurgery.
We have carried out three-dimensional, computer-assisted, functional endoscopic sinus telesurgery. Surgeons at different locations up to 300 km apart could not only see and transfer video images but also transfer three-dimensional computer models and manipulate them in realtime during surgery. Two different approaches were used. In the first telesurgery procedure we used M-JPEG compression and transmitted the data using fibre optic connections (ATM OC-3) at a bandwidth of 155 Mbit/s. In the second telesurgery procedure video images were transmitted over four E1 digital lines, amounting to about 8 Mbit/s of bandwidth, with better compression standards, such as MPEG1 and 2. We found that MPEG2 video compression produced the best picture quality for the operating field and endoscopic cameras. For conferencing and consultation between two or more connected sites during the surgery, we used JPEG and MPEG1 video compression with audio. The main feature of our three-dimensional telesurgery was the use of three-dimensional modelling of the operative field. This is important for emergency surgical interventions. We do not advocate that inexperienced surgeons operate on patients, not even with the guidance of a remote surgeon. However, three-dimensional telesurgery may become very valuable for experienced surgeons in the future.