Orbital Arteriovenous Fistula around the Optic Nerve Treated by Transvenous Embolization

Intraorbital arteriovenous fistula (AVF) is a very rare disease; therefore an optimal treatment strategy has not yet been established. Here we describe the use of high-resolution cone-beam computed tomography (CBCT) and selective angiography to visualize the detailed anatomy of orbital vessels. The information provided by the intraoperative imaging led to a change in treatment strategy and eventually to successful transvenous coil embolization. A 55-year-old man presented with a 4 months history of right exophthalmos, chemosis and diplopia. Magnetic resonance (MR) imaging demonstrated a dilated superior orbital vein. Cerebral angiography showed an intraorbital AVF fed by the branch of the ophthalmic artery and drainage to the superior orbital vein (SOV) and inferior orbital vein (IOV). Superselective angiography and high-resolution CBCT with diluted contrast medium clarified that feeders of the AVF came from the first segment of the ophthalmic artery, and the shunt located surrounding an optic nerve sheath. Transvenous embolization via IOV with coils occluded the AVF. Detailed analysis of intraorbital vessels using high-resolution CBCT and selective angiography led to successful treatment by transvenous coil embolization.