Idiopathic intracranial hypertension

Background

  • Also known as pseudotumor cerebri/benign intracranial hypertension (BIH)
  • Cause is idiopathic, but believed be due to impaired CSF absorption at arachnoid villi
  • Associated with OCPs, vitamin A, tetracycline and thyroid disorders

Clinical Features

  • Headache
    • Tend to be worse at night or first thing in the morning
    • Frequently starts as dull occipital pain, may become diffuse and throbbing
  • Nausea and Vomiting
  • Vision blurring
  • Irregular menses or amenorrhea

Differential Diagnosis

Evaluation

  • Young, obese women
  • Headache (worse in AM / with manuvers increasing ICP)
  • Papilledema (optic atrophy/vision loss)
  • Neuro Exam frequently normal
    • May have cranial nerve palsies in severe, most often CN 6

Work-Up

  • CT scan (negative or slit-like ventricles)
  • LP (Opening pressure >25)
    • CSF lab studies by lumbar puncture are negative
    • No special CSF studies need to be sent, unless differential includes etiologies for infection, hemorrhage, etc
  • CT or MR venogram (to rule out cerebral venous sinus thrombosis)

Management

  • Repeat LPs (decrease CSF pressure) - large volume LPs on the order of 30-40 cc of CSF
  • Acetazolamide 500mg BID (decrease CSF production)
  • Furosemide 20mg PO BID, give potassium supp as needed
  • Weight loss
  • CSF Shunt
  • Optic nerve sheath fenestration

Disposition

  • Admit for:
    • Severe pain
    • Focal findings
    • Vision changes
  • Otherwise, discharge with ophtho follow up for formal visual field monitoring

External Links

See Also

References