Computer-navigated contouring of craniofacial fibrous dysplasia involving the orbit.

Virtual surgical planning and computer-aided surgery were used to treat a mono-ostotic fibrous dysplasia of the right zygoma. Mirroring of the contralateral zygoma sets the target for the contouring of the affected zygomatic bone. An optical system for computer-guided surgery was used. Instruments were calibrated and visualized in real time on screen. Achievement of the virtually set target for the orbitozygomatic anatomy was assessed during surgery. Postoperative computed tomography and clinical follow-up confirmed an excellent result with regard to facial symmetry and eye bulb position. The volume of the orbit was increased from 24.2 to 26.0 mL compared with a contralateral orbital volume of 25.7 mL. Computer-guided surgery may be a useful tool in the surgical reduction of craniofacial fibrous dysplasia.