Dural Carotid Cavernous Fistula (Grand Rounds)
- 63-year-old male presented with a two-month history of left eye swelling
- Associated with pain and horizontal diplopia
- Also reports decreased vision for the past few months
- VAcc: 20/25-1; 20/50+1
- Pupils: Round and Reactive OU, no RAPD
- IOP: 10; 26
- EOM: Full OD; -3 abduction OS otherwise full EOM in all other directions OS
- Cavernous sinus thrombosis
- Carotid-cavernous fistula
- Cavernous sinus tumors
- Orbital tumors
- Thyroid orbitopathy
- Idiopathic Orbital Inflammation
- Orbital cellulitis
- A CT/CTA of the patient’s brain was performed, given high suspicion for a cavernous sinus lesion (Note: MRI was not performed since patient has a pacemaker).
- Cerebral angiogram was performed and showed a left carotid cavernous fistula fed by branches of the left external carotid artery and, to a lesser degree, the right external carotid artery and left internal carotid artery.
- Dural carotid cavernous fistula
- Direct carotid cavernous fistula – Arise most commonly secondary to a traumatic tear of internal carotid artery within the cavernous sinus. It can also rarely arise secondary to a spontaneous aneurysm rupture.
- Dural carotid cavernous fistula – Arise from connections between dural branches of the internal or external carotid arteries and the cavernous sinus. Pathophysiology is somewhat unknown. Two major hypotheses:
- Associated with occlusion of adjacent draining venous dural sinuses. This results in arterialization of venous blood flow and subsequent formation of an arteriovenous shunt.
- Arise from congenital arteriovenous shunts that are normal variants. Often in the setting of hypertension / atherosclerotic disease, these congenital shunts proliferate into a carotid cavernous fistula.
- The patient was started on Cosopt (dorzolamide hydrochloride-timolol maleate)for the elevated IOP in the left eye
- Neurosurgery was consulted for angiography and embolization of the left carotid cavernous fistula
Prognosis and Future Directions
- The overall prognosis for dural CCF is very good. There is very minimal increase in mortality rates and generally 20 to 50 percent of cases spontaneously resolve.
- Patients with mild ocular symptoms can be closely monitored with regular ophthalmology exams (checking visual acuity, IOP, EOM and dilated fundus exam).
- Patients with mild exposure keratopathy can be treated with aggressive lubrication.
- Patients experiencing diplopia can be treated with prism or occlusion therapy and IOP-lowering medications can be started if IOP is substantially elevated.
- The main indications for intervention with angiography are: visual deterioration, intolerable diplopia, elevated IOP despite maximal medical therapy, proliferative retinopathy, proptosis with untreatable corneal exposure and patients with cortical venous drainage.
- Transvenous embolization is typically used when intervention is necessary. In difficult cases, retrograde cannulation of superior or inferior ophthalmic vein can be performed to access the CCF for coiling.
- Successful closure is reported to occur in 80 to 100 percent of cases following embolization.
- Miller NR. Neurosurg Clin N Am. 2012 Jan;23(1):179-92.
- Barrow DL, Spector RH, Braun IF, et al. Classification and treatment of spontaneous carotid-cavernous sinus fistulas. J Neurosurg.1985 Feb;62(2):248-256.
- Miller NR. “Carotid-Cavernous Sinus Fistulas,” Walsh and Hoyt’s Clinical Neuro-Ophthalmology, 6th ed. (Baltimore: Lippincott, Williams & Wilkins, 2005) pp. 2263-2296.
- Ang M, Sng C, Milea D. Optical coherence tomography angiography in dural carotid-cavernous sinus fistula. BMC Ophthalmol. 2016 Jul 7;16:93.
- Debrun GM, Viñuela F, Fox AJ, et al. Indications for treatment and classification of 132 carotid-cavernous fistulas. Neurosurgery. 1988 Feb;22(2):285-9.
- Ishijima K, Kashiwagi K, Nakano K, et al. Ocular manifestations and prognosis of secondary glaucoma in patients with carotid-cavernous fistula. Jpn J Ophthalmol. 2003;47:603-8.
- Jonathan Kim, MD, Associate Professor of Clinical Ophthalmology, email@example.com
- Nadim Rayess, MD, PGY-2 Ophthalmology Resident, firstname.lastname@example.org