BLINDNESS AFTER REDUCTION OF FACIAL FRACTURES

Blindness in patients suffering maxillofacial trauma is usually caused by optic nerve or optic canal injuries. It is, however, an uncommon c omplication of facial trauma, with a reported incidence of only 2 to 5 percent.(1-6) Blindness may also follow surgical repair of facial fra ctures. Many mechanisms, such as intraoperative direct nerve injury,(7 ) retinal arteriolar occlusion associated with orbital edema,(8-11) or delayed presentation of indirect optic nerve injury sustained at the time of the initial trauma,(12) have been implicated in causing this b lindness. In this article, four cases of visual loss after surgical re pair of facial trauma are reported. In a review of the University of M aryland Shock Trauma experience with facial trauma over 11 years, we d iscovered that 2987 of the 29,474 admitted patients (10.1 percent) sus tained facial fractures, and that 1338 of these fractures (44.8 percen t) involved one or both of the orbits. One thousand two hundred forty of these patients underwent operative repair of their facial fractures . Three patients experienced postoperative complications that resulted in blindness, a total incidence of only 0.242 percent. Postoperative ophthalmic complications seem to be primarily mediated by indirect inj ury to the optic nerve and its surrounding structures. The most freque nt cause of postoperative visual loss is an increase in intraorbital p ressure in the optic canal. When our data were added to the summarized cases, blindness was attributable to intraorbital hemorrhage in 13 of 27 cases (48 percent). In addition, 5 cases in our review attribute t he visual loss to unspecified mechanisms of increased intraorbital pre ssure, bringing the total cases of visual loss caused by intraorbital pressure or hemorrhage to 18 of 27 cases, or 67 percent. Within the re stricted confines of the optic canal, even small changes in pressure p otentially may cause ischemic optic nerve injury.