A computer-assisted three-dimensional virtual osteotomy system for orthogna
thic surgery (CAVOS) is presented. The virtual reality workbench is used fo
r surgical planning. The surgeon immerses in a virtual reality environment
with stereo eyewear, holds a virtual "scalpel" (3D Mouse) and operates on a
"real" patient (3D visualization) to obtain pre-surgical prediction (3D bo
ny segment movements). Virtual surgery on a computer-generated 3D head mode
l is simulated and can be visualized from any arbitrary viewing point in a
personal computer system.