This presentation describes the principles of pure enophthalmos repair. Pure enophthalmos is defined as enophthalmos resulting from an isolated disruption of the internal orbit. The primary goal of surgery then is to restore the normal shape and volume of the orbital cavity. Procedure begins with an intraoperative traction and duction test. Traction test assesses the mobility of orbital soft tissues, while the duction test assesses passive mobility of individual extraocular muscles. The second step is to mobilize and retrieve intraorbital soft tissues. This can be extremely difficult to do because these prolapsed soft tissues have become adherent to the interorbital nerve, the fracture segments, and sinus mucosa within the maxillary sinus or ethmoid air cells. It's important to remember that these prolapsed soft tissues can balloon well beyond the margins of the defect, and this makes surgery particularly challenging. Mobilization of prolapsed soft tissues can be facilitated by simply making the defect larger, and I do this using a neurosurgical instrument called a cloward. Intraoperatively, we expose the lateral shelf superiosteally and then the medial shelf. We then can cross the malleable retractors to identify and demonstrate the prolapsed soft tissues between. If these are impossible to retrieve, we then employ the cloward to make the defect larger. As the bony shelves are removed, this greatly simplifies the section and retrieval of all the prolapsed contents with identification of the infraorbital nerve as seen below. Identification of the posterior shelf of the defect is technically challenging, and there are some additional measures that are sometimes required to access this posterior shelf. One of those measures is a transantral approach, which provides an ancillary access to the orbital floor. To an upper buccal sulcus incision, the anterior wall of the antrum can be removed, and the orbital defect can be visualized or palpated. As demonstrated in this model, the prolapsed soft tissue contents can be readily seen, and digital manipulation can even reduce these prolapsed contents to facilitate intraorbital dissection. In very large defects or in the presence of very significant adhesions, the Tessier marginotomy provides an extremely effective ancillary measure. An osteotomy is performed above the infraorbital nerve, segment is removed, and this provides direct visualization of the margins of the defect, the prolapsed tissues, as well as the orbital cavity. Interoperably, the inferior rim is osteotomized and removed to provide access. The white arrow demonstrates adhesions between the prolapsed orbital contents and the infraorbital nerve. The same white arrow now shows those adhesions having been dissected free, skeletonizing the infraorbital nerve, and on your right, you see the completed reconstruction. The final maneuver is to obliterate the intraorbital defect with an implant that restores orbital volume and shape. This implant must obliterate the entire defect and must rest on all circumferential bony margins of the defect. Clinical example showing pure left enophthalmos repair, restores global position effectively, as well as ocular projection. Thank you.

enophthalmos

orbital surgery

cloward instrument

transantral approach

orbital implant