This week is eye week!
An obese 20 year old woman presents to your clinic with a headache. She describes it as pulsatile and awakens her at night. The pain is worse with eye movement. There is some nausea, vomiting, transient visual disturbances such as visual loss and double vision, and tinnitus. You do a neurologic exam on her and find that she cannot abduct her eyes and she has decreased visual acuity. The opthalmic exam is significant for this finding:
The rest of the neurologic exam is normal. A lumbar puncture is performed and pressure is >250 mmH2O (increased) but otherwise CSF is normal. Neuroimaging does not show a hydrocephalus; ventricles look normal.
Challenge: What does this young woman have?
Image is shown under fair use.