Découverte d'une fistule durale du sinus sigmoïde cliniquement caverneuse avec des signes ophtalmologiques controlatéraux : à propos d'un cas

We report the case of an 87-year-old patient who developed a dural arteriovenous fistula of the sigmoid sinus with progressive exophthalmia in the opposite eye. The patient had a unilateral decrease in visual acuity; the vessels of the conjunctiva were dilated, and a progressive central retinal vein occlusion occurred in the left eye. A dural carotid cavernous fistula of the right sigmoid sinus was diagnosed with an angiography exam and was successfully treated with embolization of the arteriovenous shunt using Onyx®. A central partial facial nerve paralysis occurred after embolization and spontaneously resolved in 6 months. Six months after the treatment, visual acuity improved to 7/10 and the exophthalmia and central retinal vein occlusion signs regressed. Dural arteriovenous fistulae are abnormal shunts between a collateral vessel of the carotid artery and the cavernous sinus; the unilateral pulsating exophthalmia is the most frequent associated symptom. Cerebral MRI is useful to analyze indirect signs of the arteriovenous shunt showing an abnormal dilatation of the veins, but angiography of the carotid artery is essential to confirm the diagnosis. Furthermore, it allows treatment of the fistula at the same time, the main complication being the embolization of normal vessels close to the abnormal shunt. The clinical expression of the dural arteriovenous fistula on the opposite eye is infrequent and is related to the presence of complex septae within the cavernous sinus, resulting in a bilateral drainage of the cerebral venous system. The early diagnosis and management of the disease is necessary to improve the visual prognosis.