Superior ophthalmic vein cutdown and craniotomy for sylvian vein access in the treatment of a bilateral spontaneous indirect carotid-cavernous fistula

The authors discuss the first reported case of bilateral spontaneous indirect carotid-cavernous fistula (CCF) treated by a hybrid open-endovascular approach bilaterally. A 74-year-old man presented to the emergency department following 1 month of progressive right-eye proptosis with increased intraocular pressure. Cerebral angiography confirmed bilateral indirect type D CCF. Attempts to access the cavernous sinus through the petrosal sinuses were unsuccessful. The right-sided CCF was successfully treated via surgical exposure of the superior ophthalmic vein for endovascular deployment of coils and liquid embolic agent. The left-sided CCF was similarly treated after gaining cavernous sinus access via craniotomy to catheterize the left sylvian vein. The video can be found here: https://stream.cadmore.media/r10.3171/2025.7.FOCVID25103