Purpose:
To report a case of spontaneous direct carotid-cavernous fistula causing abrupt loss of vision.
Case report:
A 50-year-old woman with systemic hypertension but no history of ocular disease developed sudden proptosis, frozen eye, subconjunctival hemorrhage and loss of vision in her left eye over 2 hours. Imaging studies revealed a direct carotid-cavernous fistula. Management for high intraocular pressure was promptly initiated and the patient was referred to a neurosurgery service, but she refused any surgical intervention. Ultimately, she accepted to undergo manual carotid artery compression which resulted in significant reduction in the proptosis, but she lost all vision permanently.
Conclusion:
Direct carotid-cavernous fistula can occur spontaneously and should be taken into account in patients with signs suggestive of direct carotid-cavernous sinus fistula even without history of trauma or connective tissue disorder.