Computer-assisted three-dimensional planning in craniofacial surgery.

Three-dimensional surface reconstruction from computed tomographic (CT) data has been used to plan craniofacial operations. Cephalometric and anthropometric databases were integrated with three-dimensional CT reconstructions to quantitate the skeletal deformity and to assist in the design of the surgical procedure. Interactive techniques were developed to simulate osteotomies and skeletal movements in three dimensions on the computer-generated surface images. The ocular globes were referenced to position the orbital segments; i.e., the osteotomized segments were transposed into normal anatomic relationship with respect to the eyes. The measurements from the computer graphic simulation were used intraoperatively to establish the correct position of the skeletal segments.