Carotid-cavernous sinus fistula after external ethmoid-sphenoid surgery. Clinical course and management.

The occurrence of a carotid-cavernous sinus fistula following transethmoidal-sphenoid sinus surgery is unusual. The etiology of this complication is related to the variations in anatomic position of the carotid artery and in the thickness of bone overlying the artery in the lateral sinus wall. In the case reported herein, the clinical course was complicated by the development of cranial nerve palsies and ocular ischemia. The patient's symptoms worsened following an attempted to close the fistula with a microcatheter balloon and isobutyl-cyanoacrylate embolization. Dramatic improvement in the patient's condition was obtained by subsequent occlusion of the carotid artery on the side of the fistula with a microcatheter balloon.