We asked you about this 27 year old female who presented with a 3-day headache. After looking at her lumbar puncture results, the diagnosis is….
a. Benign Intracranial Hypertension
The pressure is very high! The CT was normal essentially excluding raised intracranial pressure secondary to an obstructive hydrocephalus (e.g. meningioma obstructing the 4th ventricle draining CSF). The red cells are high in the first sample of CSF but as further CSF is tapped off, this clears. This supports a slightly “traumatic” tap. Xanthochromia testing in the sample is negative, providing no evidence of a prior bleed into the CSF which has then been broken down into xanthochromia.
To diagnose a S.A.H. you have to have either blood or altered blood in the CSF. As a rule of thumb you should have “no” red cells in the CSF if its not a traumatic tap and there is no other pathological processes.
The diagnosis is BIH. This is reasonably common in young people and is not benign: untreated it can threaten sight. Treatment is via means to reduce CSF pressure e.g. repeated lumbar punctures.
