Idiopathic intracranial hypertension

Revision as of 03:16, 4 March 2020 by Hour (talk | contribs) (Evaluation)

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

Differential Diagnosis

Headache

Common

Killers

Maimers

Others

Aseptic Meningitis

Evaluation

  • Ocular exam including pupillary examination, ocular motility, assessment for dyschromatopsia (color plates). Also obtain systemic vitals such as blood pressure and temperature
  • CT (negative or slit-like ventricles).
  • Typically, MRI and MR venogram of the orbit and brain to rule out secondary causes of intracranial pressure such as cerebral venous sinus thrombosis. If normal, the patient may need LP to determine opening pressure and r/o other causes of optic nerve edema.
  • Consider ocular ultrasound (simple, non-invasive) to assess optic nerve diameter. Source: https://www.ncbi.nlm.nih.gov/pubmed/27168453
  • 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
    • Recognize that in rare cases, LP's can cause reactive meningeal enhancement (which is why some practitioners delay LP until after MRI). This practice might not be supported in cases where LP is necessary. Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5727706/
  • Outpatient visual field testing is the most important method for following these patients (Humphrey VF's)

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