Pseudotumor Cerebri Syndrome Related to a Dural Arteriovenous Fistula After Vascular Trauma

Case Presentation

YB, aged early 40s, who had a body mass index of 28 kg/m², sustained a right cervical-thoracic stabbing injury during an assault, which was treated emergently with right jugular vein ligation, inferior vena cava filter placement, and administration of more than 40 units of red blood cells. Approximately 1 year later, YB developed transient visual obscurations, morning headaches, pulse-synchronous tinnitus, and transient binocular horizontal diplopia.

Diagnostic Process

Neuro-ophthalmologic examination revealed bilateral grade 4 papilledema (Figure 1), and MRI showed optic disc enhancement without an intracranial mass, hydrocephalus, or cerebral venous sinus stenosis (CVST). Transient improvement in symptoms was obtained with acetazolamide treatment, but persistent optic disc edema and increased headache and visual obscurations 3 months after presentation prompted optic nerve sheath fenestration in the right eye. Lumbar puncture opening pressure was 43 cm H₂O with normal cerebrospinal fluid constituents. One month later, increased headaches and transient confusion developed, leading to admission to hospital for further testing. A cerebral angiogram revealed a dural arteriovenous fistula (AVF) (Figure 2) involving the right sigmoid sinus, severe venous hypertension with left transverse sinus stenosis outflow obstruction, and the right jugular vein ligation described previously.

Case Resolution

A series of 4 angiograms and embolizations (with main feeders originating from the tentorial branch of the right internal carotid artery and posterior meningeal branch from the right vertebral artery) using ethylene vinyl alcohol copolymer (Onyx; Micro Therapeutics, Irvine, CA) improved the fistula, optic disc edema, and symptoms, including headache, diplopia and transient visual obscurations. Optical coherence tomography testing provided evidence of this improvement; retinal nerve fiber layer thickness decreased from 436 to 126 μm in the right eye and 403 to 149 μm in the left eye.

Discussion

Pseudotumor cerebri is a syndrome of increased intracranial pressure without hydrocephalus, structural origin, or abnormal spinal fluid constituents. Typical symptoms include headache, papilledema with potential vision loss, transient visual obscurations, and abducens nerve palsy. Whereas the syndrome often results from idiopathic intracranial hypertension, it also may arise as a secondary complication of cerebral venous abnormalities. We present a case of secondary pseudotumor cerebri caused by dural AVF development after jugular vein ligation.

The pseudotumor cerebri syndrome can result from many primary pathophysiologies, with the most common proximal etiologies related to cerebral venous dysfunction. Increased cerebral venous pressure produces intracranial hypertension, papilledema, headache, pulsatile tinnitus, abducens neuropathy, and transient visual obscurations. Cerebral venous hypertension may result from venous occlusive disease and can occur after dominant jugular vein occlusion, although this typically occurs within weeks of the inciting event. YB’s intracranial hypertension symptoms occurred 1 year after right internal jugular vein ligation, related to the complex dural AVF fueling persistent intracranial hypertension. The dural AVF likely added to venous hypertension from the occluded jugular vein because of the arterial to venous shunting; this shunting presumably increased 1 year after the jugular injury, accounting for the increased intracranial pressure. Micieli et al¹ reported a similar case of an individual presenting with papilledema attributable to CVST who redeveloped papilledema 1 year later related to dural AVF development, with a comparable time course to YB’s, highlighting the potential timeline of dural AVF formation.

Dural AVFs represent pathologic anastomoses between meningeal arteries and dural venous sinuses, and they have a complex relationship with CVST. In a large series of dural AVFs in 69 individuals, 39% were associated with adjacent CVST.² Nonetheless, dural AVF development after cerebral venous thrombosis likely is rare; in a series of 112 participants with cerebral venous thrombosis, none subsequently developed a dural AVF.³ The origin of these dural AVFs remains unknown, with hypotheses including neovascular factors after cerebral venous thrombosis or injury, filling of potential dural AVF vessels related to venous hypertension, or both. The clinician should be aware of these tardive AVFs in people presenting with pseudotumor cerebri after cerebral venous occlusive disease.