COMPUTER-AIDED NAVIGATION IN SECONDARY RECONSTRUCTION OF POSTTRAUMATIC DEFORMITIES OF THE ZYGOMA

Augmented reality technology was used in 5 patients for secondary reco nstruction of post-traumatic unilateral deformities of the zygomaticom axillary complex. Three electromagnetic sensors interfaced to a comput er-aided navigation system (ARTMA Biomedical Inc.) were utilized. The computer navigation procedure was planned by drawing graphic lines on the CT scan at the level of the zygomatic arch, representing the outer surface of the zygoma. The desired position of the displaced zygoma w as planned by mirroring from the healthy side, using a virtual mid-sag ittal plane. These virtual graphics were presented intraoperatively on a TV monitor and also on the surgeon's see-through head-mounted displ ay. Correct reduction was assumed when the virtual line representing t he position of the zygoma before the osteotomy reached the virtual lin e defined preoperatively as the desired position. The advantages of th e technique presented are that a complete exposure of the zygomatic bo ne is no longer necessary, and coronal and subciliary incisions may be avoided unless enophthalmos correction has to be carried out, which w as in fact necessary in 2 patients. The results of zygomatic reconstru ction have been satisfactory in all 5 patients.