Evaluation of Shape and Volume Restoration of Orbit after Reduction of Orbitozygomatic Fractures

Abstract Background The appearance of the Orbitozygomatic complex (OZC) fracture terminology is contributed to the fact that a fracture in the lateral side of the midface is not strict to anatomical boundaries, however, it involves the zygoma, maxilla and orbital structures. Orbitozygomatic complex fractures are one of the most commonly encountered injuries of the craniofacial skeleton. The solid zygomatic bone acts as a part of the vertical and horizontal facial buttress, along with the malar eminence, which plays a key role in the determination of facial morphology. It forms a significant portion of the floor and lateral wall of the orbit thus it acts as one of the most common contributors to the orbital integrity, restoration of orbital volume is essential to prevent enophthalmos. Objective Evaluate restoration of orbital shape, volume and globe position in the anterior-posterior plane after reduction of zygomatico-orbital fractures. Methods This Prospective observational study was done from March 2023 to August 2023 at plastic, burn and maxillofacial department in El Demerdash Hospital, Ain Shams University. Eighteen (18) adult patients, complaining of post traumatic orbito-zygomatic fractures requiring operative intervention, were included in this study. Evaluations of orbital shape and differences between orbital volume measurements (damaged orbits compared to intact orbits before and after surgery), orbital volume calculated from area marked by delineating bony landmarks of the orbit interconnected by freehand cursor manually on a series of CT slices in the axial plane, the CT images were exported to the CMF orbital analysis software (adw4.7), where the volume was calculated automatically, Depth: measured from orbital rim to the orbital apex, from outer optic foramen to the middle point of a line passing through lateral and medial orbital rims; width: Maximal horizontal distance from lateral to medial rim and height: measured from superior to inferior margin at their maximum distance perpendicular to orbital width. Results The mean volume of the affected orbit throughout our study showed significant decrease from 24.81 ± 2.04 cm3 before the operation to 23.38 ± 2.22 cm3 after the surgical intervention (P < 0.001), indicating a highly significant difference, where volume has significantly increased on fractured side preoperative in comparison to the sound side (P = 0.016) indicating significant effect of trauma on increasing orbital volume from normal, while no statistical difference was noted (P = 0.75) between orbital volume of fractured side postoperatively 23.38 ± 2.22 cm3 and the sound side 23.24 ± 1.64 cm3, indicating proper reduction and restoration of orbital volume to near normal postoperatively, increased depth (45.46 ± 3.26), width (38 ± 2.94) and height (35.7 ± 2.98) of fractured side preoperatively; this increase was statistically significant, While Depth and width showed more increase than height; values were more statistically significant and return to near normal postoperatively (42.96 ± 2.68), (36 ± 2.88) and (34.23 ± 3.45) respectively; this decrease was still significant statistically except for height where it was non-significant, indicating better restoration of height than depth and width attributed to its lesser increase from the first place, as values of sound side weree (41.64 ± 2.25), (34.56 ± 3.25) and (34.51± 3.52) respectively. Conclusion Our study suggests that the surgical reduction of orbitozygomatic fractures has a significant role in restoration of the orbital shape, volume, and globe positioning in the anterior-posterior plane. And that enophthalmos occurrence is greatly influenced by increase of the bony orbital volume, also it’s affected by other factors for further research. Orbital dimensions were affected by trauma and restored to near normal after reduction but showed no major shape changes of the conical orbit.