Bilateral carotid-cavernous sinus fistula: Case reports and review of the literature

Carotid-cavernous fistula (CCF) is an abnormal vascular connection between the carotid artery and the cavernous sinus. There are various classifications based on haemodynamic, aetiology or anatomically. Haemodynamic classification is based on whether the fistula is high or low flow. Etiologically, it can be secondary to trauma or can develop spontaneously due to pre-existing aneurysm or medical conditions predisposing to arterial wall defects. Bilateral CCFs are very rare. We present two cases of bilateral CCF – one secondary to trauma and other occurred spontaneously. Both the patients presented with the signs of raised intraocular pressure – decreased vision, chemosis, proptosis and ophthalmoplegia. Magnetic resonance imaging and digital subtraction angiography confirmed a bilateral CCF. Both the patients underwent two settings of endovascular embolisation procedures, and complete embolisation of bilateral CCF was achieved. Available literature is unclear about the aetiology of bilateral CCF, technique of endovascular embolisation and the prognosis of bilateral CCF. In our both the cases, we were able to achieve complete embolisation in two settings.