Navigation-aided reconstruction of medial orbital wall and floor contour in cranio-maxillofacial reconstruction

The reconstruction of the anterio-posterior inclination of the medial aspect of the orbital floor, despite a wide 360 degrees exposure, including coronal and conjunctival incisions, is a challenging task in severe injuries of the orbit with massive comminution and complete displacement of the medial orbital wall and orbital floor. Out of a total of 20 patients with orbital fractures, five underwent a surgical intervention of repositioning the medial aspect of the orbital floor and especially the transition area between the orbital floor and medial orbital wall, using navigation-aided procedures. Using the mirroring tool of the Stryker-Leibinger STN-system, post-operative CTs indicated an average difference of the globe position of -4.9% between the operated side and the unaffected side, depending on the position of the medial aspect of the orbital floor. Navigation-aided procedures proved to be an essential precondition for achieving precise and predictable results in orbital reconstruction. In such cases, unlike those with an intact medial orbital wall remnant as a surgical target, bone grafts for reconstruction of the orbital floor cannot be implanted as onlay grafts.