Indirect carotid-cavernous fistula of low-flow type: Color Doppler Imaging of retrobulbar vessels findings

Abstract

Background. Carotid-cavernous fistulas (CCF) of low-flow type are the results of development of communication between small arteries and veins of cavernous sinus. Aim. To assess the role of CDI of retrobulbar vessels in the study of two patients with CCF of low-flow type. Methods. We have used a sonographer with 9MHz linear probe. Results. The initial diagnosis was suspected clinically: both patients presented unilateral chemosis and orbital bruit. It was sustained by CDI of retrobulbar vessels: reversed flow in the superior ophthalmic vein, with a venous arterialisation and confirmed with complete selective digital subtraction angiography, which is essential for a correct diagnosis( early opacification of veins draining cavernous sinus, etc). Conclusions. CDI of retrobulbar vessels is a repetitive non-invasive technique, which is used for monitoring carotid-cavernous fistulas of low-flow type, because they are sometimes a self-limiting pathology (spontaneous venous thrombosis).