Cavernous carotid fistula

A cavernous-carotid fistula is an abnormal connection between the cavernous sinus in the brain and the carotid artery. The cavernous sinus is a venous system located in the brain in the center of the head directly behind the orbits and nasal sinuses. The internal carotid arteries are close by as well as some of the cranial nerves, which control movement of the eyes and sensation of the face. When a fistula occurs it can cause a swelling in the veins where the venous and arterial blood flows connect. This swelling is caused by the pressure differences within each system. A fistula may occur spontaneously, or may be the result of trauma to the head.


A cavernous carotid fistula can cause compression of the nerves and other structures within area leading to the symptoms. Symptoms include eye pain, swelling or redness in the eye, outward bulging in the eye (proptosis), double or blurry vision (diplopia), dilated pupils, or deviation of the eye.

Diagnosis and treatment

Imaging includes a CT scan, an MRI scan. Sometimes an angiogram is done. Twenty to fifty percent of CC fistulas self-thrombose, meaning they occlude themselves. If symptoms are present, then the fistula is treated with an angiogram with embolization of the fistula by placing coils, glue, and/or a vascular plug.

Lindsey Parker PA-C and Justin F. Fraser MD 

Stroke and cerebrovascular disorders »

Page last updated: 1/25/2016 3:00:02 PM