Determining the best endovascular approach: a case report of transvenous coiling for direct carotid cavernous fistula

Abstract

Direct carotid-cavernous fistula (CCF) is an abnormal high-flow arteriovenous connection between the cavernous segment of the internal carotid artery (ICA) and the cavernous sinus (CS), most commonly resulting from trauma. The high-flow nature of the fistula leads to arterialized venous hypertension within the CS and retrograde cortical venous reflux, which clinically manifests as proptosis, chemosis, and ocular bruit. Transarterial embolization (TAE) is often the preferred treatment for direct CCF because it typically involves a single, direct arterial feeder. However, it carries the risk of distal embolization into the arterial or venous system. This case reported a traumatic direct CCF successfully managed via transvenous embolization (TVE). A 48-year old male presented with typical symptoms of CCF following trauma. Its angioarchitecture included a single feeding artery from the left C4 segment of the ICA, a fistulous point in the left posterior CS, and venous drainage via the left inferior petrosal sinus (IPS) with venous engorgement of the left superior ophthalmic vein (SOV). The transfemoral TVE approach via the IPS was selected because it provides the shortest and most direct route to the posterior CS. Embolization was performed via three detachable coils deployed at the fistula site, resulting in complete obliteration of the fistula. While TVE avoids the potential complications associated with distal arterial embolization, it does carry a risk of venous congestion and, in rare cases, technical rupture of pial veins. Nonetheless, in the treatment of direct CCF, TVE has demonstrated efficacy comparable to that of TAE in achieving significant flow reduction and, in many cases, complete obliteration of the fistula.