Carotid-cavernous fistula

Carotid-cavernous fistula
Classification and external resources

Oblique section through the cavernous sinus.
DiseasesDB 2152
eMedicine oph/204 radio/134
MeSH D020216

A carotid-cavernous fistula (CCF) results from an abnormal communication between the arterial and venous systems within the cavernous sinus in the skull. It is a type of arteriovenous fistula. As arterial blood under high pressure enters the cavernous sinus, the normal venous return to the cavernous sinus is impeded and this causes engorgement of the draining veins, manifesting most dramatically as a sudden engorgement and redness of the eye of the same side.

Contents

Causes

Carotid cavernous fistulae may form following closed or penetrating head trauma, surgical damage, rupture of an intracavernous aneurysm etc. or in association with connective tissue disorders, vascular diseases and dural fistulas.

Classification

Many types of classification have been proposed for CCF, based on the anatomy, pathophysiology and aetiology. They may be divided into low-flow or high-flow, traumatic or spontaneous and direct or indirect. One of the most popular classifications divides CCF into four varieties depending on the type of arterial supply.

Type Description
A Fistulous supply from the internal carotid artery
B Supply from the dural branches of internal carotid artery
C Supply from the dural branches of external carotid artery
D Combined forms

Symptoms and presentation

While CCF is not a lethal disease, its symptoms can be disabling and include bruit (a humming sound within the skull due to high blood flow through the arteriovenous fistula), progressive visual loss, and pulsatile proptosis or progressive bulging of the eye due to dilatation of the veins draining the eye. Pain is the symptoms that patients often find the most difficult to tolerate.

Patients usually present with sudden or insidious onset of redness in one eye, associated with progressive proptosis or bulging.

They may have a history of similar episodes in the past.

Diagnosis

This is based on MRI scan with MRA/MRV, CT angiogram and a cerebral DSA.

Treatment

Best treated by balloon embolisation via a catheter in the internal carotid artery

External links