Carotid cavernous fistula

Abstract

A carotid-cavernous sinus fistula is an abnormal communication between arteries and veins within the cavernous sinus. It is generally categorized into high-flow, direct CCF and low-flow, indirect CCF. CCF formation is caused by either trauma or spontaneously. CCF affects the structures within the cavernous sinus, including the internal carotid artery (ICA), abducens nerve (CN VI), oculomotor nerve (CN III), trochlear nerve (CN IV), ophthalmic branch of the trigeminal nerve (CN V1), and maxillary branch of the trigeminal nerve (CN V2). Accordingly, the clinical presentations of CCF may involve ophthalmologic or neurologic systems. The radiographic investigations include noninvasive imaging modalities such as CT scanning, MRI, CT/MR angiography, and invasive cerebral angiography, the gold standard for CCF diagnosis. The goal of treatment is to completely occlude the fistula while maintaining normal blood flow through the ICA. Treatment options for CCF closure include external compression of the ICA, endovascular interventions, radiosurgical interventions, and surgical interventions. Endovascular intervention has become the treatment of choice for most CCFs. It provided favorable outcomes with low rates of recurrence, morbidity, and mortality.