Abstract 461: Variations in Embolization Strategies for Carotid Cavernous Fistulas: A Case Series
Authors: Krothapalli N. , Fowler J. , Patel S. , Bruno C. , Ollenschleger M. , Sussman E. , Mehta T. 
Published: January 2025

Introduction
Carotid cavernous fistulas (CCFs) are pathological shunts between the carotid artery and cavernous sinus. They are a devastating cause of visual loss, periocular disfigurement and orbital symptoms. Endovascular treatment has become the mainstay of treatment for CCFs, with prompt intervention preventing complications and further symptom progression.

Methods
A review of our CCF database was conducted, identifying five relevant cases. We highlight a variety of direct or indirect CCFs treated with various materials and embolization strategies with subsequent clinical improvement.

Results
CASE 1: A 38‐year‐old man with a history of cranial fractures and left epidural hematoma from recent motor vehicle accident presented with left eye redness, retro‐orbital pain, and intermittent diplopia. A cerebral angiogram revealed bilateral petrous‐cavernous dissections of internal carotid arteries (ICAs) resulting in Type A direct CCFs. He underwent endovascular reconstruction with two overlapping Pipeline stents followed by transvenous coil embolization of bilateral cavernous sinus and superior ophthalmic veins. Further coil embolization and an additional stent were necessary. Subsequent angiograms showed gradual improvement with resolution of eye symptoms one year later.
CASE 2: A 66‐year‐old woman with hyperlipidemia experienced acute eye vision loss and swelling in her left eye following pulsatile tinnitus. Angiography identified a Type B left CCF supplied by bilateral meningohypophyseal trunk branches with retrograde venous drainage. An occluded inferior petrosal sinus (IPS) was catheterized to reach the fistulous point and transvenous coil embolization was performed. Post‐treatment, her exophthalmos improved and follow‐up angiogram confirmed cure of the fistula.
CASE 3: A 77‐year‐old woman with history of hypertension and prior heparin‐induced thrombocytopenia presented with left facial twitching and droop, with concern for new onset seizures. During hospitalization, she developed right frontotemporal intraparenchymal hemorrhage. Angiogram was notable for Type D indirect right CCF contributing to significant cortical venous reflux. Treatment involved advancing a microcatheter through an occluded right IPS to reach the fistulous point before Onyx embolization. Follow‐up angiogram at 4 months confirmed angiographic cure.
CASE 4: A 59‐year‐old woman with a history of tobacco use and childhood encephalitis presented with right eye chemosis and swelling. Angiography revealed a right Type D indirect fistula with retrograde drainage into the superior and inferior ophthalmic vein. She was treated with Onyx embolization via transvenous approach using the right IPS with complete obliteration of shunting. Post‐operatively, her periorbital swelling improved.
CASE 5: A 28‐year‐old woman with history of left subclavian pseudoaneurysm presented with progressive left‐sided visual issues, elevated intraocular pressure, and conjunctival injection. Angiography revealed a left Type A direct CCF with venous drainage via an enlarged superior ophthalmic vein into a hypertrophied angular and facial vein. She underwent embolization with Pipeline stents extending across the cavernous ICA and coil embolization. Post‐treatment, her vision and pressure improved significantly.

Conclusion
Our case series illustrates various embolization strategies for treating CCFs. We highlight the importance of timely intervention, utility of newer flow‐diverting stents, significance of navigating occluded IPS, and exploring alternative access routes to the cavernous sinus. Mastery of endovascular techniques and adaptability to technical challenges are crucial for enhancing patient outcomes.