Zygomatic surface marker-assisted surgical navigation: a new computer-assisted navigation method for accurate treatment of delayed zygomatic fractures.
OBJECTIVE
To describe a new method of zygomatic surface marker navigation to treat delayed unilateral zygomatic fractures.


METHODS
The computed tomography (CT) data for 6 patients were obtained before surgery and imported into the surgical planning software. After 3-dimensional (3D) construction and segmentation, 3D cylindrical-shaped objects in stereolithographic format were placed in position and merged with the data from the fractured segments to mark the area for surface reduction. Data from the unaffected side were used to guide the reduction data for the segments with markers. During surgery, the surface markers were marked by drilling holes in the fractured bones in a process guided by the surgical navigation plan established before osteotomy. The segments were then reduced to the predetermined places using the positions of the hole markers as guides. 3D image comparisons and axial CT measurements were used to evaluate navigation accuracy and bone symmetry.


RESULTS
Six patients with unilateral delayed zygomatic fractures were treated using this approach. The mean deviation between the postoperative 3D images and the reduction navigation plan for the 6 patients was +1.24 mm and -1.4 mm. The mean width deviation between the affected and unaffected sides was 1.28 mm, and the mean eminence deviation was 1.22 mm. All patients were followed up for at least 3 months and experienced no obvious complications.


CONCLUSIONS
Zygomatic surface marker-assisted surgical navigation can simplify the navigation planning for surgery and avoid the complex protocols needed to create the surgical templates. The navigation accuracy was acceptable, and all 6 patients obtained good facial symmetry.
Attending, Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, China.
Yang
Y
He
Yi
Y
Zhang
Jin-gang
JG
An
Xi
X
Gong
Zhi-qiang
ZQ
Feng
Chuan-bin
CB
Guo
D000328:Adult; D015415:Biomarkers; D057210:Delayed Diagnosis; D061827:Dimensional Measurement Accuracy; D005260:Female; D005592:Fracture Fixation; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D008953:Models, Anatomic; D025321:Surgery, Computer-Assisted / Q000295:instrumentation / Q000379:methods; D036542:Tomography, Spiral Computed; D015051:Zygomatic Fractures / Q000000981:diagnostic imaging / Q000601:surgery*
D015415:Biomarkers