People with IIH




Idiopathic intracranial hypertension (IIH), also known as benign intracranial hypertension or pseudotumour cerebri, is a condition with an unknown cause or causes. The condition is associated with raised fluid pressure around the brain. The fluid that cushions the brain is called cerebrospinal fluid (CSF).

It can cause disabling daily headaches and visual loss, which can be permanent. The raised brain pressure can press the nerves supplying the eye (also known as papilloedema) and this can affect vision.

The most common symptoms of IIH include:

  • Headaches
  • Visual obscurations
  • Pulsatile tinnitus
  • Back pain
  • Dizziness
  • Neck pain
Less common symptoms that are sometimes reported include:
  • Blurred vision
  • Memory problems
  • Nerve pain
  • Double vision
Read the consensus guidelines on IIH management here: https://jnnp.bmj.com

How is IIH diagnosed?

To diagnose IIH you may see a neurologist and an ophthalmologist. Doctors need to talk to you about what you have been experiencing and perform a physical examination. It is important that other conditions are ruled out before diagnosing IIH.

It is essential that other conditions such as venous sinus thrombosis (blood clot in brain), anaemia (lack of red blood cells) and certain drugs such as some antibiotics or vitamin A containing drugs are ruled out, as they require different treatment.

To be diagnosed with IIH you will need brain scans and a lumbar puncture (LP), sometimes called a spinal tap. It is vital that lumbar puncture reading is performed with you relaxed and lying on your side for the reading to be accurate. For more information, see the IIH UK Information on Lumbar Puncture Leaflet.

For doctors to be able to diagnose IIH all the following 5 things need to be present:

  1. Papilloedema (swelling of the eye nerves).
  2. Normal neurological examination (sixth nerve palsy causing doublevision is allowed).
  3. Normal brain imaging. This is usually with computerized tomography (CT) or magnetic resonance imaging (MRI) scans. They should alsoinclude a scan of the veins of the brain to exclude venous sinusthrombosis.
  4. Normal brain fluid (CSF) analysis.
  5. Elevated lumbar puncture opening pressure above 25cm (for some people a pressure above 25cm may be normal for them)

(For the criteria for IIH without papiloedema, see the IIHWOP leaflet)


How is it treated

The majority of people with will have medical (drugs) treatment for IIH and headaches. Less than 1 out of 10 people with IIH will have surgical treatment. 9 out 10 people with IIH are overweight and weight loss has been found to be the most effective treatment. For further information on weight loss see the IIHUK Weight and IIH leaflet.

Medical treatments for IIH have been assessed by a medical review body (the Cochrane review) and they have suggested that more trials are required to understand what are the best drug and surgical treatments for IIH. Acetazolamide (DiamoxTM) is often prescribed for IIH, for further information on acetazolamide see the IIHUK acetazolamide drug information leaflet.

There are two main types of surgery:

  1. Shunt surgery – one end of a flexible tube is put into the fluid filled space in your brain (ventricle) or your spine (lumbar) and the other end in another part of your body, such as your abdominal cavity (peritoneum).
  2. Optic nerve sheath fenestration – a small window is created in the layer (sheath) around your eye nerve to allow the fluid to drain away.

For further information on surgery in IIH see the IIHUK shunt surgery in IIH leaflet and optic nerve sheath fenestration leaflet.

How do you treat headaches caused by IIH?

There are no drugs specially designed for IIH headaches. There is evidence that weight loss improves headaches in IIH (Newborg 1974; Kuppersmith 1998; Johnson 1998; Sinclair 2010).

Your health care professional may use medications to help with the headaches. For further information on headaches see the IIHUK Headache in IIH leaflet.

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