Complications of the Anophthalmic Socket

Abstract

The anophthalmic socket is subject to four major deformities: enophthalmos, exposure, eyelid malposition, and socket contraction. Enophthalmos occurs when there is a lack of soft tissue volume, creating a sunken or hollow appearance. Exposure occurs when a previously placed orbital implant erodes through the ocular surface. Eyelid malposition occurs largely as a consequence of wearing of a prosthesis. Socket contraction occurs when there is insufficient ocular surface area and fornix depth to accommodate a mobile prosthesis. Understanding these disfigurements and their treatments is the goal of this chapter. Anopththalmic enophthalmos is an acquired condition that occurs when there is a lack of orbit volume after removal of the eye. In a typical case 6 mL of volume is lost with removal of the eye. An orbital implant will replace 2 to 4 mL of volume, and a prosthesis will replace 1 to 2 mL of volume. This leaves a volume deficit of 1 to 3 mL. This typical volume deficit can be exacerbated by fat and muscle atrophy secondary to surgery or antecedent trauma. In cases of eyes removed secondary to orbital trauma, unrepaired orbital fractures expand the bony orbit, further exacerbating the lack of orbital soft tissue. After removal of the eye the orbital implant and the inadequate volume of orbital soft tissue tend to settle toward the orbital floor, creating more of a volume deficit in the superior orbit. The orbital fat is somewhat liquid and much of the preaponeurotic fat in the upper eyelid flows posterior and inferior, creating the hollow appearance in the superior fornix of the anophthalmic socket. This deformity is referred to as the superior sulcus deformity and is present in some degree in the majority of anophthalmic sockets. 24-1-1 Diagnosis. History-taking should direct the ophthalmologist toward the cause of the patient’s anophthalmos. If the eye was lost to trauma, the possibility of orbital fractures expanding the orbital volume and exacerbating the condition should be considered. If the socket was radiated, the possibility of radiation-induced orbital soft tissue atrophy should be considered.