Pseudotumor cerebri from cranial venous obstruction.

Dural sinus hypertension from cerebral venous outflow impairment is a cause of pseudotumor cerebri. The authors documented six such patients: two with unilateral neck dissection, one with surgical ligation of the dominant sigmoid sinus, two with thrombosed central intravenous catheterization, and one with dural sinus thrombosis. The site of cerebral venous outflow obstruction was variable and identified in three patients with computed tomography, conventional magnetic resonance imaging, magnetic resonance angiography, and/or angiography. Magnetic resonance angiography used in two patients characterized the venous flow pattern and identified the site of obstruction, confirming magnetic resonance angiography as an effective noninvasive blood flow technique in diagnosing and following these patients. Three patients were treated successfully with medical therapy and one patient with optic nerve fenestration. The two patients with thrombosed central venous catheters had serious systemic illnesses and suffered permanent visual loss.