Idiopathic intracranial hypertension (IIH)

Idiopathic intracranial hypertension (also known as pseudotumour cerebri and formerly benign intracranial hypertension) is a condition classically seen in young, overweight females.

Risk factors

• obesity
• female sex
• pregnancy
• drugs
  • combined oral contraceptive pill
  • steroids
  • tetracyclines
  • retinoids (isotretinoin, tretinoin) / vitamin A
  • lithium

Features

• headache
• blurred vision
• papilloedema (usually present)
• enlarged blind spot
• sixth nerve palsy may be present

Management

• weight loss
  • whilst diet and exercise are important, medications such as semaglitide and topiramate may be considered by specialists. Topiramate is particularly beneficial as it also inhibits carbonic anhydrase
• carbonic anhydrase inhibitors e.g. acetazolamide
• topiramate is also used, and has the added benefit of causing weight loss in most patients
• repeated lumbar puncture may be used as a temporary measure but is not suitable for longer-term management
• surgery: optic nerve sheath decompression and fenestration may be needed to prevent damage to the optic nerve. A lumboperitoneal or ventriculoperitoneal shunt may also be performed to reduce intracranial pressure