Long-term clinical outcome of spontaneous carotid cavernous sinus fistulae supplied by dural branches of the internal carotid artery

We report the long-term clinical outcome of spontaneous carotid cavernous sinus fistulae (CCF) originally supplied by branches arising from the internal carotid artery (Barrow's type B), or type-D lesion that became type B after particulate embolization. A total of 55 patients was included in this study. Their angiography revealed that cortical drainage was absent, and that the arteries supplying the fistulae originated in the dural branches of the internal carotid artery. Thirty-two patients had type-D lesions, which became type-B lesions after obliteration of the external carotid supply by endovascular treatment. The other 23 patients had type-B lesions documented by angiography, and had no embolization. The follow-up period ranged from 8 to 144.5 months. Clinical cure was achieved in 39 patients (70.9%), improvement in eight patients (14.5%), the lesion remained stable in four patients (7.3%), and was aggravated in four patients (7.3%). The number of drainage veins is the only radiographic factor that could predict the outcome. Those patients with single draining veins had a better chance of complete remission. The outcome between the group with original type D lesions after embolization and the group with original type B revealed no statistically significant difference. The time-course to complete cure was significantly shorter in the group with embolization of the external carotid supply. In the four patients whose symptoms were aggravated, embolization was performed, and the result was excellent. The clinical outcome of type-B CCF, or type D converted to type B, is good. Previous external carotid artery embolization can significantly shorten the time to complete cure. Aggressive treatment should be reserved for those who have aggravated symptoms.