Chronic Carotid Cavernous Fistula - A Case Report.

Introduction/Background: Carotid cavernous fistula (CCF) is an abnormal communication, traumatic or spontaneous in origin, between the carotid arterial system and the cavernous sinus, resulting in short-circuiting of arterial blood into this intracranial venous system. Patients will often present with ocular signs and symptoms such as conjunctival chemosis, proptosis, pulsating exophthalmos, diplopia, ophthalmoplegia, orbital pain, audible bruits and decreased visual acuity, which can be attributed to secondary glaucoma, ischemic optic neuropathy or chorioretinal dysfunction. Treatment is usually accomplished through trans-arterial or trans-venous embolization. Methods: Case report of a single patient presenting with ocular manifestations from a chronic carotid cavernous fistula. Results: We report the case of a 92 year old female patient presenting with gradually decreasing visual acuity on her left eye (LE). She had a chronic history of red eye interpreted as allergic conjuntivitis. On examination, best corrected visual acuity LE was 3/10 (Snellen); biomicroscopy revealed exuberant conjunctival vascular tortuosity on a 'medusa head' pattern and conjunctival chemosis. On gonioscopy, grade IV Schaffer open angle was observed on all quadrants but blood was present on Schlemm's cannal. On fundus exam, papillary and macular edema were present, as well as exuberant retinal arterial and venous tortuosity and engorgement. Suspecting a low debit arterial-venous fistula, the patient underwent orbital and cranial MRI scan which showed increased extraocular muscle thickness, superior ophthalmic vein dilation and left side cavernous sinus dilation, confirming the diagnosis. She was referred to a neuroradiology consult but her advanced age was deemed contraindicate to invasive intervention. Conclusions: CCV is a rare clinical entity often presenting with ocular manifestations. A high index of suspicion for its characteristic signs and symptoms is of indisputable importance in both establishing an early diagnosis and designing a suitable treatment plan. Acknowledgements: No financial interests to declare. [ABSTRACT FROM AUTHOR]