Traumatic optic neuropathy accompanying orbital grease gun injury

We report a case of traumatic optic neuropathy accompanying a grease gun injury to the orbit. A 48-year-old man with a grease gun injury visited our clinic with decreased visual acuity, proptosis and limited extraocular movement (EOM). Orbital CT revealed a crescent mass of fat in the medial intraconal space. The grease was exuded from a lacerated conjunctival wound. The visual evoked potential (VEP) test demonstrated a decreased response in the left eye. Proptosis and EOM were improved after surgical removal of the grease. Systemic high-dose corticosteroid therapy was administered for suspected traumatic optic neuropathy, after which VEP nearly recovered, while visual acuity was slightly improved. A second surgery for traumatic cataract did not further improve visual acuity.