Eye Diseases - Temporal Arteritis
What is Giant Cell Arteritis?
Giant Cell Arteritis is a condition which affects the arteries. If left untreated it can cause serious sight loss.
How does Giant Cell Arteritis cause sight loss?
Arteries are blood vessels which take fresh blood to all the parts of the body. With Giant Cell Arteritis the medium sized blood vessels become swollen. The most common artery to swell is the temporal artery.
The temporal artery provides blood to the optic nerve. The danger to sight occurs because the artery can become so swollen that it is easily blocked. If this happens then the optic nerve is starved of blood and sight can be lost.
What causes Giant Cell Arteritis?
At the moment the exact cause of the disease is unknown.
It usually only affects people over the age of 55 and is most common in people over 75. Giant Cell Arteritis seems to affect more women than men.
Giant Cell Arteritis is sometimes related to other problems. Most commonly polymylagia rhuematica, this is a condition which causes pain in the shoulders and hip joints. Polymylagia rhuematica is also associated with problems of blood supply. Often people with polymylagia rhuematica go on to develop Giant Cell Arteritis. However Giant Cell Arteritis can often occur on its own without any other medical conditions.
How do I know that I have Giant Cell Arteritis?
Often the first sign of Giant Cell Arteritis is pain on chewing. Often people are able to chew for a while but eventually the pain, becomes so bad they have to stop. If this happens you should be seen at the hospital as soon as possible.
Sometimes first sign that someone has Giant Cell Arteritis is a headache. This headache is usually concentrated in the temple region of your head. Just above your eye and near to your hairline. Often it is tender to touch and things like combing your hair may be painful.
Sometimes the temporal artery swells and can be seen around your eye, this too is tender to touch. There are other symptoms such as fever, weight loss and generally feeling unwell.
If you develop pain on chewing or a new kind of headache especially in the temple area which is more often painful than not, you should see your GP.
How might it effect my sight?
Giant Cell Arteritis causes the artery walls to swell which means that the space the blood has to travel through becomes thinner. Sometimes the artery develops sticky patches which collect cells from the blood, making the tunnel even thinner. If left untreated, these sticky patches can interfere with the amount of blood passing through the arteries. This can cause the artery which brings blood to the optic nerve to swell, reducing the amount of fresh blood the optic nerve receives. Unfortunately this can cause the optic nerve to become damaged by the lack of fresh blood. This can have a serious affect on vision. It can cause people to lose all the sight in one eye.
Can Giant Cell Arteritis be treated?
Luckily Giant Cell Arteritis can be treated before it gets to this stage. If you go to your GP with a new headache in the front part of your head along with some of the other symptoms mentioned, they may well send you to the hospital. An ophthalmologist (eye specialist) can then confirm a diagnosis and prescribe a course of treatment that should prevent sight loss.
How does the ophthalmologist diagnose Giant Cell Arteritis?
As well as taking a history from you about how the condition is affecting you, the doctor may well perform a number of tests. They will take a blood sample to determine your ESR. ESR stands for erythorcyte sedimentation rate. This measures the consistency of your blood.
A normal rate is your age divided by two. So someone 60 years old ESR should be around 30, anything higher than 50 is considered a sign that there is some kind of swelling in the body which might mean Giant Cell Arteritis.
There is also another blood test called the CRP (C reactive protein) that is often performed. This test measures the level of a protein in the blood which is only present when there is acute swelling in the body. This means it is a good indication for swelling caused by Giant Cell Arteritis.
The ophthalmologist may well also perform a biopsy on your swollen temporal artery. This involves a small operation which can be performed as an outpatient. Using a local anaesthetic, the doctor removes a small part of your artery and examines it under a microscope. With this they can see whether Giant Cell Arteritis has affected your artery and confirm your diagnosis.
How is Giant Cell Arteritis treated?
If Giant Cell Arteritis is caught early it can be treated with steroid tablets. Steroids help to reduce swelling, this mean that the swelling in the arteries can be reduced. The blood can then flow freely to the optic nerve again. This prevents the loss of vision.
The steroid treatment is started at a high dose and is reviewed closely. Over a period of time, sometimes a long period, the dose of the steroids can be reduced so that eventually you can stop taking them or control the disease on a very low dose.
What if I have already lost sight in one eye?
Sometimes if the symptoms of Giant Cell Arteritis are missed then people can suddenly lose sight in one eye. If this happens most people go straight to casualty since it is obvious that something is wrong. There they will see an ophthalmologist who will prescribed high dose of steroids usually intravenously (through a drip) this means you have to stay in hospital.
The high dose steroids are an attempt to bring down the swelling in the hope that re-establishing the blood supply quickly can bring sight back. Usually however this sight loss is permanent and the steroids are being used to stop the Giant Cell Arteritis affecting the sight in the other eye.
Can Giant Cell Arteritis lead to blindness?
Giant Cell Arteritis is a condition that can seriously affect vision, although only about 25 per cent of cases will cause the sight loss described if left untreated.
It is better not to take any risk. Any new pain on chewing, persistent headache, symptoms such as the swelling of the artery or pain when touching the temples should be reported to your GP.
This means that you can get the steroid treatment promptly and not risk the loss of your sight.