Orbital Arteriovenous Fistula Coexistent with an Arteriovenous Hemangioma: A Rare Occurrence and Review of Literature.

BACKGROUND

Orbital arteriovenous fistula (AVF) is a rare entity with only 17 cases reported so far. An arteriovenous hemangioma is a distinct entity of an angioma that most frequently affects the skin. However, to our knowledge, there has not been a case arising in the orbit.

CASE DESCRIPTION

A previously healthy, 73-year-old man had progressive proptosis for 1 month. At presentation, the patient showed considerable proptosis, hyperemia in the lower eyelid, chemosis, and total ophthalmoplegia on the right side. Computed tomography and magnetic resonance imaging revealed a round retro-orbital mass, 23 mm in maximal dimension, and lying in the inferomedial aspect of the orbit with an irregular-shaped lesion in the orbital apex. Cerebral angiography detected an orbital AVF fed by the ipsilateral maxillary and ophthalmic arteries and draining into the inferior ophthalmic vein. Stain of the retro-orbital mass was not identified. A transvenous coil embolization via the facial and superior ophthalmic veins achieved complete isolation of the AVF with satisfactory outcome. Two months later, the orbital mass, well circumscribed and lacking perilesional hemosiderin deposition, was microsurgically resected via a lateral orbitotomy. Histological diagnosis was consistent with an arteriovenous hemangioma.

CONCLUSIONS

An AVF and arteriovenous hemangioma may simultaneously develop in the same orbit. In patients with symptomatic orbital AVF and coexisting other orbital pathology, strategies should be carefully planned before setting about the treatment.