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

Work-Up

1. CT scan (negative)
2. LP (Opening pressure >25)
3. MR venogram (to r/o cerebral venous sinus thrombosis)

Clinical Features

1. Headache
2. Nausea and Vomiting
3. Vision blurring

Diagnosis

1. Young, obese women
2. Headache (worse in AM / with manuvers increasing ICP)
3. Papilledema (optic atrophy/vision loss)
   1. can be visualized with ultrasound
4. Neuro Exam frequently normal

Differential Diagnosis

• Aneurysm rupture and Subarachnoid Hemorrhage
• Brain tumor
• Encephalitis
• Head Injury
• Hydrocephalus (increased CSF)
• Hypertensive brain hemorrhage
• Intraventricular hemorrhage
• Cerebral venous sinus thrombosis
• Meningitis
• Subdural Hematoma
• Status epilepticus
• Stroke

Treatment

1. Repeat LPs (decrease CSF pressure)
2. Acetazolamide 500mg BID
3. Weight loss
4. CSF Shunt
5. Optic nerve sheath fenestration

Disposition

• Admit for:
  • Severe pain
  • Focal findings
  • Vision changes
• Otherwise, discharge w/ ophtho f/u for formal visual field monitoring

Source

Tintinalli