Page 18 - Advanced concepts in orbital wall fractures
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Chapter 1
orbital rim and this is often used to fixate an implant for orbital wall reconstruction. The orbital process of the palatine bone is in fact the posterior ledge and usually remains intact after an orbital wall fracture, due to its position and thickness20. Together with the inferior orbital rim this is an important landmark, as it indicates the desired dorsal position of an implant and facilitates posterior support. It is located anterior to the superior orbital fissure, so the surgeon should be careful when approaching this area20. When visualisation of the posterior ledge is difficult, an alternative landmark is the posterior wall of the maxillary sinus21. The infraorbital nerve can also serve as a guide for the surgeon in both the depth and direction of the dissection along the orbital floor22. This structure is often involved in trauma and as such cannot be used as reliable guidance in most cases. The inferomedial strut can be additionally used as a landmark to identify the transition from the orbital floor to the medial wall. Several ligaments are attached to the inferomedial strut for globe support. This strut is often affected in complex fractures23. Apart from the identification of anatomical landmarks, the success of orbital reconstruction is influenced by the implant material.
A wide variety of implant materials are used to reconstruct an orbital wall fracture. The goal of orbital reconstruction is to restore the pretraumatised orbital anatomy and function, predominantly for the correction of enophthalmos and diplopia. Implant materials must have certain characteristics to achieve this. The ideal material has good stability and fixation, has an ideal architecture or contouring abilities to restore volume and shape, is biocompatible, facilitates drainage of fluids, has no donor site morbidity, is radiopaque, and is readily available at an acceptable price6. Titanium implants adhere to most of these demands and are widely used, either as preformed custom plates, patient-specific implants, or titanium meshes for intraoperative bending. Autologous bone grafts used to be the gold standard based on biocompatibility. The disadvantages are donor site morbidity, unpredictable resorption rate, and difficulty to shape the graft. An alloplastic material like titanium is now considered the gold standard, yet still a lot of research is performed to find the best suitable biomaterial for orbital reconstruction.































































































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