Astigmatism is one of the most common eye conditions – most people have it to degree. It is often mistakenly referred to as ‘stigmatism’.

Astigmatism occurs when the cornea or lens are shaped more like a rugby ball – more curved in one direction than the other. And light is not focused on one point on the back of the eye. For instance, vertical lines may be clearer than two horizontal or vice versa.

This means that the image at the back of your eye is not as sharply focused and vision may be blurred. Corneal astigmatism is when the cornea is a distorted shape and lenticular astigmatism occurs when the lens is distorted.

To focus images, the eye has two parts – the cornea and the lens. The cornea is the curved ‘window’ at the front of the eye. When the cornea and the lens inside the eye area are a regular symmetrical shape all incoming light is sent the same way to make a sharply focused image onto one single point on the retina at the back of the eye. The retina is the light-sensitive area at the back of the eye, like the film in a camera. If light is only focused on one part of the eye, vision will be clear.

Most people with astigmatism are born with the condition, although it can develop throughout life. A condition called keratoconus can also change the shape of the cornea with age and this can cause astigmatism. Rarely, astigmatism can be as a result of an injury or eye disease. Usually a person with astigmatism will have other visual problems, such as long or short sightedness.

Those people with a small degree of astigmatism may not experience any problems. Those whose astigmatism is more significant may experience any or all of the following:

* Blurring and distortion of near or far-away objects
* Headaches when trying to focus
* Senstivity to light
* Tired and dry eyes

In some cases, astigmatism is present at birth as the size and shape of the eye is developed in the womb. It may be due to environmental and genetic factors, but the exact cause is not always known. Sometimes an astigmatism can develop after an eye injury, surgery or eye disease. Astigmatism is not caused by factors such as reading in poor light, squinting or watching too much television.

Although astigmatism is extremely common and afffects most people to some degree, many may not need any corrective action. Most people who wear glasses or contact lenses may have some degree of astigmatism. Treatments include corrective spectacle lenses, special contact lenses or surgery.

People with astigmatism cannot see horizontal or vertical lines clearly at the same time. This is what makes objects appear blurry or out of focus.

For those who have astigmatism, an optometrist, ophthalmic surgeon or eye specialist should carry out a full eye examination to assess the full scale of the problem. Options for correction can be discussed in full. Corrective glasses, special contact lenses or surgery are all options. A regular eye test is vital to maintaining healthy eyes. We should each aim to have our eyes tested every two years at least.

US class action over cataract eye operations

London: A group of elderly people left fighting for their sight following failed cataract surgery is taking leading American lens companies to court in a bid to win millions in compensation.

OAPS from across the UK suffered years of misery after major problems with the lenses used in operations to clear their cataracts.

Within months of their original surgery victims like Joan Steel, 78, from Morecambe, Lancashire, and Thomas Allcott, 70, of Tamworth in the West Midlands were struggling to see again.

And many of the elderly men and women were forced to go through second operations in a desperate bid to improve their vision.

Some even suffered further eye conditions caused by the trauma of trying to rectify their sight.

More than 300,000 cataract operations are carried out in the UK every year.

Bad packaging is thought to have contaminated lenses used in their surgery

Legal firm Birchall Blackburn represent 179 people worldwide who are taking on the American lens manufacturers in a bid to win compensation.

Eight elderly people in Britain – including Mrs Steel and Mr Allcott – face a court showdown with one specific Florida-based company, Medical Development Research, who supplied lens type SC60B-OUV which was used in their failed surgery.

But the numbers both globally and in the UK are rising all the time as more people become aware what has caused the problems with their sight.

Up to 50,000 people could have been affected by the alleged contaminated lenses worldwide. In Britain the figure could be as high as 2,400 people.

Mr Allcott, a jeweller for 50 years in Birmingham’s jewellery quarter said: “Trying to sort out my sight has taken four years of my life – but even now my vision is not the same.

“The operation on my left eye was simple enough but within months of the lens going in my vision was cloudy.

“Initially I was told my vision wouldn’t get any worse, but that was no good to me. As a jeweller I need my sight.

“I had a second operation to improve my sight which involved making an incision and replacing the lens and there was always the chance it could go wrong.

“Fortunately it went well – but I still had to spend the next two years with stitches in my eyes which was frustrating.

“I have also developed another condition which I believe is down to the surgery I have had on my eye and as a result the vision in my left eye is slightly bent.”

Mrs Steel underwent her first eye operation in 1998 and was soon suffering from cloudy vision.

Despite under going corrective laser surgery and a second operation the grandmother of two has been left with poor vision. One eye is still too painful to touch.

“I expected my vision to be improved,” she said. “Instead I have been through years of problems.

“I need help getting around now and I have hurt my legs from falling over repeatedly.”

Mr Allcott added: “I decided to fight for compensation because the last few years have been very tough.”

Duncan Stackhouse of Birchall Blackburn, said: “We still really don’t have any idea how many people have been affected by these defective lenses – the clients we are representing could just be the tip of the iceberg.

“Taking on the manufacturer through the American courts is a brave step for them to take.

“All our clients are at the stage in their lives when they should be relaxing and enjoying themselves – unfortunately, because of what has happened, they have not been able to do that.

“They should not have to sweep their suffering under the carpet and struggle on – they have every right to fight for some recompense.”