Optic neuropathy, a warning for cerebral venous sinus thrombosis and underlying dural arteriovenous fistulae.

Cerebral venous sinus thrombosis (CVST) typically presents as headache, papilledema, and seizures. A dural arteriovenous fistula (DAVF) is a rare intracranial vascular malformation, and common symptoms include headache, pulsatile tinnitus, and stroke. The occurrence of CVST as a complication of DAVF is infrequent. Moreover, optic neuropathy presenting as the initial symptom of CVST and secondary DAVF is also unusual. We present a case of a patient with optic neuropathy and persistent intracranial hypertension who underwent head magnetic resonance imaging, which indicated CVST. She received normative anticoagulant and dehydration therapy; however, a repeated lumbar puncture showed dramatically increased intracranial pressure. Further digital subtraction angiography revealed an intracranial DAVF. The patient was finally diagnosed with a DAVF and secondary CVST. This case indicates that intractable optic neuropathy could be an uncommon indicator for CVST and secondary DAVF. Early diagnosis and early treatment are essential for visual rehabilitation and prognosis improvement.