Unilateral Abducens Nerve Palsy due to Bilateral Dural Carotid Cavernous Fistula

Dural carotid-cavernous fistula (CCF) is characterized by arteriovenous communications between the meningeal branches of the internal or external carotid arteries and the cavernous sinus. Although the triad of chemosis, proptosis, and ocular bruit has been regarded as a classic sign of CCF, dural CCF often lacks these features. Dural CCF is a rare cause of ophthalmoplegia, and so it may be overlooked when the classic symptoms are absent. We report herein a case of bilateral dural CCF that presented as unilateral isolated abducens nerve palsy.