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

Abstract

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.

Keywords: Optic neuropathy; cerebral venous sinus thrombosis; digital subtraction angiography, magnetic resonance imaging; dural arteriovenous fistula; intracranial hypertension; papilledema.

Figure 1.

Head magnetic resonance imaging (MRI) (a and b), diffusion weighted imaging (c), and MRI with gadolinium enhancement (d) results were normal, while magnetic resonance venography displayed cerebral venous sinus thrombosis in the left sigmoid sinus, rear of the superior sagittal sinus, and internal jugular vein (e and f, black arrows). Optic nerve MRI with gadolinium enhancement revealed hyperintensities on T2-weighted images and enhancement at the bilateral optic nerve sheath and optic disc in the orbits (g–i, white arrows).

Figure 2.

Advanced neuroimaging evaluation with digital subtraction angiography. The dural arteriovenous fistula was situated in the left lateral sinus (a, external carotid artery, venous phase). The bilateral occipital arteries branched from the posterior cerebral artery (b–d, external carotid artery, arterial phase, white arrows).

Figure 3.

The venous sinuses were shown previously during the arterial phase of cerebral angiography (a) internal carotid artery, arterial phase, white arrowhead). The arteriovenous malformation was located in the left posterior cranial fossa and was supplied by the anterior choroidal artery (b) internal carotid artery, arterial phase, white arrowhead), and venous drainage occurred via the transverse sinus and sigmoid sinus (b internal carotid artery, arterial phase, black arrowhead). The malformation was an accessory vascularization secondary to the dural arteriovenous fistula (DAVF) and participated in shunting superfluous blood flow volume. The dominant feeding arteries of the DAVF were the left posterior inferior cerebellar artery and the left posterior cerebral artery (c and d vertebral artery, arterial phase, white arrowhead).