The indication and application of computer-assisted navigation in oral and maxillofacial surgery-Shanghai's experience based on 104 cases.

OBJECTIVE: To explore the indication and application of computer-assisted navigation in oral and maxillofacial surgery.

PATIENTS AND METHODS: One hundred and four patients including 34 zygomatic-orbital-maxillary fractures, 27 unilateral TMJ ankylosis, 29 craniofacial fibrous dysplasia, 9 mandibular angle hypertrophia, 3 cartilage/bone tumours of jaw and 2 cases with facial foreign bodies were enrolled in this study. CT scans were performed and data was saved in DICOM (digital imaging and communications in medicine) format. The osteotomy lines, amount and range of resection, the reduction position of bony segments and the reconstruction morphology was determined and displayed by preoperative simulation with mirroring and superimposing procedures. All operations were performed under the guidance of navigation system. The accuracy of navigation was evaluated by comparing the postoperative CT 3-D model with preoperative surgical planning.

RESULTS: Through registration, an accurate match between the intraoperative anatomy and the CT images was achieved. The systematic error checked by computer was within 1 mm. All operations were performed successfully with the guidance of real-time navigation. The mean error between virtual simulation and surgical results was 1.46 ± 0.24 mm. All patients healed uneventfully and function and profile was improved significantly.

CONCLUSIONS: With the opportunity to perform preoperative planning, surgical simulation and postoperative prediction, computer-assisted navigation shows great value in improving the accuracy of maxillofacial surgery, reducing operation risk and postsurgical morbidity, and restoring facial symmetry. It is regarded as a valuable technique in these potentially complicated procedures.