Hx: 35 yo female complains of a severe headache. It is frontal, bilateral, and radiates to her whole head. It has been worsening for days and not responding to meds. She has a history of migraines and pseudotumor cerebri (idiopathic intracranial hypertension). She tried her midrin and over the counter meds for the headache without relief. Pain is constant and severe and now associated with episodes of blindness that are increasing in frequency and duration. Near total vision loss, both eyes, begins in the peripheral vision, not positional, and intermittent. Nausea is associated with the headache, but there is no fever, neck pain, or vomiting. Records show numerous visits for headaches with several CT scans of the head in the past year, all normal.
PMhx: migraines, pseudotumor cerebri, depression, polycystic ovary syndrome
SocHx: No tobacco or drugs. Occasional etoh .
Meds: Midrin prn, celexa, metformin, acetazolamide (stopped over a month ago)
Exam:
• Vital signs: pulse 90, BP 160/90, RR 12, temp 98.6, O2sat 100% RA
• General: obese female in moderate distress due to headache
• Head: normal
• Eyes: pupils equal, EOM normal, vision normal, moderate photophobia
• ENT: normal
• Resp: clear, normal
• Cardiovascular: regular rate and rhythm, normal pulses, no murmurs
• Abdomen: soft, non-tender, obese
• Extremities: normal
• Neuro: cranial nerves intact, sensation and motor normal all extremities
ED Course:
• An attempt at fundoscopic examination is made but the patient is intolerant of the exam due to photophobia.
• IV pain medication is given
• A drop of cyclogyl is placed in each eye.
• A short while after, another attempt at fundoscopic examination is made demonstrating bilateral sever papilledema.
• The patient is consented for lumbar puncture which is performed with an opening pressure exceeding 40cm H2O (>400mm H2O) in the lateral decubitus position with legs extended.
• A total of 40ml of cerebrospinal fluid is removed before normal pressure is achieved.
• The patient has almost immediate resolution of her headache with no further episodes of blindness.
• CSF analysis is normal.
• The patient is discharged home with a prescription for her acetazolamide and instructed to follow up with her neurologist.
Discussion:
Psuedotumor Cerebri, also known as idiopathic intracranial hypertension, is a condition of increased intracranial pressure without the presence of any structural lesions or cerebrospinal fluid abnormalities. Although it was previously named “benign intracranial hypertension” the name was misleading. The condition is serious and can lead to severe headaches and permanent blindness if not treated.
The classic presentation is an obese woman of childbearing age with papilledema and complaints of severe headache. However, symptoms can include:
• headache (92%)
• transient visual changes (72%)
• intracranial noises (60%)
• sustained vision loss (26%)
• back pain (53%)
• double vision due to sixth nerve palsy
One study noted no correlation between pseudo tumor cerberi and iron deficiency anemia, thyroid disease, pregnancy, antibiotic use, or oral contraceptive use.
Differential diagnosis should include:
• structural causes of elevated intracranial pressure (masses)
• cerebral venous thrombosis
• obstructive hydrocephalus
• choroid plexus papilloma (increases CSF production)
• malignant hypertension
Multiple small observational studies have demonstrated the benefits of weight loss in this population, with as little as 6% weight loss being more effective than other therapies. In addition, carbonic anhydrase inhibitors, like acetazolamide, reduce the rate of CSF production but typically result in only modest improvement in symptoms. Topiramate also inhibits carbonic anhydrase and is known to have additional benefits in migraine control, and to a lesser degree in weight loss. Surgical therapies include CSF shunts and optic nerve sheath fenestration. These are reserved for patient who has failed optimal medical therapy.