OBJECTIVETo study a reliable CT measuring method for quantitative diagnosis of unilateral zygomatic complex fracture and operation guiding.

METHODS20 zygomatic complex fracture patients needed operation were collected, three dimensional CT images of all patients were measured and analyzed by Mimics software before operation. Standard anatomy points of bilateral zygomatic complex and adjacent bone were selected, then the distance of two same selected points and the angles of three same selected points were measured by Mimics software. Compared to uninjured side, the different value of the distance and the angle of injured side zygomatic complex were acquired, zygomatic complex fractures were operated based on the different value. All patients were examined by three dimensional CT postoperatively, and the different value of the distance and the angle of both side were measured using same method to pre-operation. Therapy effects were analyzed based on the data of different value of the distance and the angle.

RESULTS1) The displacement of zygoma of most patients was backward and inward. The different value of the distance between uninjured and injured side was less than 2 mm, and the different value of the angle was less than 1 degrees. All patients reached the three-dimensional symmetric, surgical results were satisfactory in recovery of occlusion and mouth opening. 2) The zygomatic arch protrusion angle was about 138.50 degrees +/- 1.15 degrees, zygomatic prominent angle was about 132.72 degrees +/- 0.89 degrees. The two data were normal distribution.

CONCLUSIONThree dimensional CT measurements of zygomatic complex can be achieved for the quantitative measurement of spatial displacement, and have directive significance for the reduction of the zygomatic complex fractures.