Orbital Cyst after Repair of Blow-out Fracture

ABSTRACT

When blow-out fracture repair is performed, many implants including Silastic, Supramid, Porous polyethylene and others have been used to pervent reherniation of orbital tissue. Complications associated with implants include implant extrusion, orbital infection, fistula formation, implant migration, extraocular muscle entrapment, globe elevation, protosis and orbital cyst formation. The latter was known as a rare late complication of blow-out fracture repair. We report two cases of orbital cyst which developed after blow-out fracture repair with alloplastic implants. These patients developed diplopia and unliateral proptosis 7 and 10 years after repair of blow-out fracture, respectively. In these cases, orbital CT scan revealed retrobulbar cyst-like structures surrounding the orbital implant. At sufgery, a fibrous capsule surrounded the previously inserted orbital implants and was filled with dark brown mucoid material in both cases. These cysts were lined by squamous epithelium with cholesterol cleft and hemosiderin laden macrophage collection. Proptosis and diplopia were resolved after surgical removal of the cyst. These cases illustrate that it is important for us to be aware of the complication of late cyst formation around alloplastic implants after repair of blow-out fracture.