Background: We present a rare case of a left-sided carotid cavernous fistula (CCF) that presented 15 months post initial trauma with right-sided ophthalmic signs and symptoms. Highlighted is a contralateral endovascular approach to treating this traumatic CCF. Methods: Described is a case of a left-sided CCF caused by a self-inflicted gun shot wound to the head that was initially treated conservatively by neurosurgery and opthomology. The patient presented 15 months later with headache, acute right-sided periorbital swelling, severe right eye and facial pain. Results: Angiography confirmed the presence of a left-sided CCF with preferential drainage into the right cavernous sinus and right superior ophthalmic vein. The left internal carotid artery (ICA) was shown to be narrow and irregular. Multiple attempts to navigate the micro catheter through the vessel were unsuccessful. Instead, the fistula was embolized using a contralateral approach through the right internal carotid artery and across the anterior communicating artery. Imaging post-operatively confirmed successful occlusion of the CCF. Conclusions: This case is a rare example of a left-sided ICA occlusion secondary to trauma presenting 15 months after the initial injury with right-sided ophthalmic signs and symptoms. It is also one of only a few in the literature that describe successful treatment of traumatic CCF through a contralateral approach.