Alcohol embolization of carotid-cavernous indirect fistulae

Carotid-cavernous fistulae (CCFs) are abnormal communications between the carotid artery and cavernous sinus that may present with rapid visual deterioration and extraocular paresis as a result of increasing intraocular pressure requiring emergent treatment to preserve vision. We present a technique of balloon-assisted ethanol embolization of the cavernous carotid artery supply to indirect CCFs providing immediate reduction in intraocular pressure with symptomatic improvement.

We reviewed clinical and angiographic data and present a retrospective case series illustrating six patients who underwent endovascular embolization because of worsening visual acuity and extraocular motility disorder caused by CCFs. Cerebral angiography revealed significant blood supply from the cavernous carotid artery to these CCFs. We performed ethanol embolization of these branches with distal balloon protection.

Five of the six patients experienced immediate and sustained (mean follow-up, 21 mo) decreases in intraocular pressure, with significant symptom improvement. One patient experienced cavernous sinus thrombosis after conclusion of embolization, which caused a temporary worsening of symptoms that improved gradually over time.

Many surgical and endovascular options are available to treat indirect CCFs. Absolute ethanol is a liquid agent that causes immediate vessel sclerosis and occlusion, which makes it a dangerous but potent liquid embolic agent. With distal temporary balloon protection to prevent migration of ethanol, we achieved excellent clinical and angiographic results using absolute ethanol to embolize the cavernous carotid supply to indirect CCFs. This represents a safe and effective method of endovascular management of this complex vascular anomaly.