Management of Secondary Orbital Deformities

Abstract

SUMMARY Prevention is the best treatment for secondary deformities. In general, failure to understand the pathophysiology of orbital injury is the cause of incomplete correction. In order to perform secondary procedures, one must understand the primary management and the deviations that result in the need for secondary treatment. Orbital fractures must be separated into at least two major categories. The zygoma fracture is the most common, results from a lateral to medial blow against the cheekbone, and is the usual cause of enophthalmos. Proper treatment requires reduction in three planes, examination of the anterior maxillary buttress through a buccal incision, and fixation with at least two rigid plates. Failure to properly reduce this fracture or displacement due to masseteric muscle pull produces deformity of the lateral canthus, lower eyelid, and cheek prominence. The extent of the fracture is best diagnosed on CT scan for both primary and secondary treatment. When incomplete reduction has led to secondary deformity, the primary treatment is reosteotomy of the zygoma and replacement in a more medial position. The purpose of this secondary procedure is to correct not only the volume discrepancy within the orbit but the lack of cheek prominence and the associated lateral canthal deformity. The blow-out fracture results when the force to the orbit is transferred around its circumference. In this circumstance, rather than bones breaking at sutural attachments, energy is transmitted into the interior of the orbit. Fractures then occur along the orbital floor and, in 50% of patients, along the medial wall.6 These are best diagnosed on preoperative CT scan. Prevention of enophthalmos requires exploration of both the posterior extent of the orbital floor fracture and the medial wall fracture. Late treatment is performed by volume augmentation behind the axis of the globe along the lateral wall, posterior orbital floor, and medial wall in the region of the lamina papyracea. The emphasis in secondary treatment is on the enophthalmos, with the secondary superior sulcus syndrome and facial asymmetry. Primary treatment of either fracture type, as well as the more complex, comminuted fractures, should restore an acceptable appearance in the majority of patients. Although secondary treatment of enophthalmos is also successful, management of the associated soft tissue injuries can be much more difficult. Individuals electing to treat orbital fractures should be expert at managing not only bony fracture but the associated soft tissues, including the upper eyelid, medial canthus, and lacrimal system. Although secondary orbital re-construction is more difficult than primary, attention to the same principles and an understanding of the pathophysiology of orbital deformity can produce consistent results at present, rather than as the exception of previous decades. Incomplete treatment of primary orbital fractures consistently produces secondary enophthalmos. Inadequate treatment of more complex orbital injuries produces enophthalmos, soft tissue deformity, and orbital cripples. Knowledge of the volume implications of orbital fracture, the different fracture patterns, and current methods of treatment has made excellent results the rule at present.