Carotid–cavernous sinus fistula with functional filtering bleb: A case report

We describe a rare case of carotid-cavernous sinus fistula (CCF) in a 91-year-old woman's right eye with a functional filtering bleb. Upon examination, best-corrected visual acuity was light perception and intraocular pressure (IOP) was 14 mmHg, and a shallow anterior chamber, a swollen filtering bleb, dilated episcleral veins, choroidal detachment, and ocular manifestations accompanied with CCF were observed. During the healing process post transcatheter arterial embolization (TAE), significant hypotony and prolonged choroidal detachment were observed. Generally, IOP elevation is known to be a common ocular manifestation in CCF cases. When CCF develops in an eye with a functional filtering bleb post trabeculectomy, no IOP elevation is observed because the aqueous humor drains from the bleb. Dilated episcleral veins and a shallow anterior chamber may be observed, and although significant hypotony can occur soon after TAE, closure of the CCF results in recovery of vision without ophthalmic intervention.