An uncommon but very serious entity that leads to three distinct types of presentations:
Headache
Seizures
Stroke
Caused by thrombosis of one of the intracerebral venous sinuses (most commonly the transverse sinus) The major risk factor is hypercoagulable disease. May be the underlying cause of a majority of cases of idiopathic intracranial hypertension.
When to suspect:
Headache with negative CT, negative LP, but high opening pressure
In any patient with new onset idiopathic intracranial hypertension (i.e. pseudotumor cerebri). Can't be formally diagnosed without a negative MRI.
Stroke syndrome that doesn't quite fit. May see bilateral infarcts in the posterior regions. These are actually venous infarcts secondary to the sinus thrombosis.
Diagnosis:
Just like a lot of other things in medicine, "If you don't think about it, you can't diagnose it."
1 in 3 head CT scans will be normal
MRI with MRV (venous phase) is the diagnostic standard
