Carotid-cavernous fistula due to contralateral orbital trauma.

Direct carotid cavernous fistula is an abnormal arterio-venous connection from the carotid artery to the cavernous sinus (CS), resulting in high-pressure arterial blood entering the low-pressure venous CS. Most often, it occurs posttrauma and presents with ipsilateral orbital signs. In this report, we describe the case of a 54-year-old man, who presented with a late-onset right-sided red eye and diplopia following contralateral (left sided) orbital trauma (road traffic accident 7 months ago). Ocular examination revealed signs of Lateral rectus palsy, axial proptosis, and elevated intraocular pressure with dilated episcleral vessels in the right eye. Clinical findings were consistent with the diagnosis of right-sided direct CCF. To our surprise, digital subtraction angiogram revealed a left CCF with prominence of signs on the contralateral side. He underwent near-total endovascular coiling of the fistula, with initial aggravation of symptoms followed by near-total resolution.