Orbital drainage from cerebral arteriovenous malformations

OBJECTIVE: To describe the neuro-ophthalmic findings in patients with orbit al drainage from cerebral arteriovenous malformations (AVMs). METHODS: We reviewed the records of 100 consecutive adult patients with cer ebral AVMs who presented to our institution during a 4-year period. All pat ients with orbital drainage were identified, and their neuro-ophthalmic eva luations were reviewed. RESULTS: Three patients (3%) were identified with orbital drainage from a c erebral AVM. The first patient presented with typical chiasmal syndrome (re duced visual acuity, bitemporal hemianopia, and optic atrophy). Magnetic re sonance imaging demonstrated a large left temporal and parietal lobe AVM wi th compression of the chiasm between a large pituitary gland and a markedly enlarged carotid artery. The second patient presented with headaches and p ostural monocular transient visual obscurations. Examination revealed norma l visual function with minimal orbital congestion and asymmetrical disc ede ma, which was worse in the left eye. Magnetic resonance imaging revealed a large right parietal and occipital lobe AVM without mass effect or hemorrha ge and an enlarged left superior ophthalmic vein. The third patient had no visual symptoms and a normal neuro-ophthalmic examination; a right parietal lobe AVM was discovered during an examination for the cause of headaches. CONCLUSION: Orbital drainage from cerebral AVMs is rare. Manifestations may include anterior visual pathway compression, dilated conjunctival veins, o rbital congestion, and asymmetrical disc swelling.