Circulating anticoagulant phenomenon manifesting as isolated intracranial hypertension.
A 28 years old male developed headache and bilateral papilloedema. Cerebrospinal fluid revealed increased opening pressure, but was otherwise unremarkable. Magnetic Resonance (MRI) imaging of the brain was normal; MRI of the neck disclosed thrombosis of the right internal jugular vein. Russel viper venom test revealed the presence of a circulating anticoagulant.