psuedomotor cerebri

Also referred to as idiopathic intracranial hypertension (IIH), is a form of communicating hydrocephalus. the pressure at the ventricles and subarachnoid space is equilibrated with the lumbar cistern.

It's safe to do a lumbar puncture in there patients and the results will yield a high opening pressure (>20mm H2O).

Criteria for Dx includes:

• increased ICP at an alert patient
• absence of neuro signs except for CN6 abnormality
• normal CSF findings, except for increased opening pressure
• absence of ventricular abnormality (MRI will show an empty sella and slit like ventricles)

Symptoms include loss of vision, pulsatile tinnitus, and CN6 palsy.

Treatment is with acetazolamide.

Vitamin A (isotretinoin is usually prescribed for acne) and OCP use can cause IIH (think obese females on isotretinoin/ OCP).