Anterior ischemic optic neuropathy after transvenous coiling of dural arteriovenous fistulas: A case report

Abstract Background A dural arteriovenous fistula (dAVF) is defined as an abnormal arteriovenous direct connection in the dura mater, with the cavernous sinus (CS) being one of the most common locations. Transarterial or transvenous embolization remains the first-line treatment for most dAVF, although these procedures are associated with rare sight-threatening ophthalmic complications. We report a case of nonarteritic anterior ischemic optic neuropathy (nAION) following successful treatment of dAVF with a coil embolization. Case presentation A 76-year-old woman complained of conjunctival hyperemia in both eyes 1 month prior to visiting our hospital. She was diagnosed with bilateral dAVF based on magnetic resonance angiography (MRA). On ophthalmic examination, her best-corrected visual acuity (BCVA) was 0.8 in the right eye and 0.7 in the left. Intraocular pressure was 27 mmHg in the right and 24 mmHg in the left. Extraocular movements were limited in all directions. Slit lamp examination disclosed red eyes with dilated corkscrew vessels. Funduscopic examination revealed normal findings in both eyes except a partial chorioretinal atrophy in the left eye. Goldmann perimetry revealed an inferior nasal defect corresponding to the chorioretinal atrophy in the left eye and normal visual field in the right eye. Transvenous coil embolization of the right CS was performed. The dAVF was completely embolized and there was no intraoperative complication. Follow-up brain MRA showed no evidence of residual dural fistula. Ten days after embolization, she developed double vision and visual disturbance in the right eye. Her right BCVA was 0.8. Fundus examination revealed pallor papilledema and splinter hemorrhages at the optic disc edge in her right eye. Fluorescein angiography showed hypofluorescence around the optic disc and a nasal lesion in the early phase. Goldman perimetry revealed lower altitudinal hemianopsia in the right eye. From these findings, nAION was diagnosed. During hospitalization, her right BCVA decreased to 0.08. Ten months later, funduscopy revealed right temporal optic disc pallor without edema, and her right visual acuity remained at 0.08. Conclusions We report a case of nAION after embolization of dAVF located in CS. This complication should be considered after embolization for dAVF.