Saturday 29 March 2014

When the lights begin to fade

When Dame Judi Dench announced she was no longer able to read scripts because of an eye condition, thousands of people understood what she was going through.
The James Bond actress, who turns 80 this year, first revealed her eyesight was deteriorating in 2012. Since then, she’s said her loss of vision means she has to learn scripts on a tape recorder, or ask someone to read them to her.
‘I can’t read anymore,’ she said. ‘I can’t paint like I used to. I try to watch movies but it’s quite difficult.’
Dench suffers from age-related macular degeneration (AMD), a painless condition that generally leads to the loss of central vision (directly in front of you). It doesn’t affect your peripheral vision so doesn’t cause complete blindness.
Although there is no cure, it can be controlled and pioneering treatments might help some people.
In public eye: British actress Judi Dench suffers from the condition
In public eye: British actress Judi Dench suffers from the condition
AMD is one of the leading causes of sight loss, with one in every ten people over 65 estimated to have the condition to some degree. It tends to be more common in women than men and in those over 50.
The condition comes on with advancing age but can develop in those as young as 40, says Andy Luff, ophthalmic surgeon at Optegra Eye Hospitals in the UK.
‘It is progressive damage that affects a part of the retina at the back of your eye called the macula,’ he says.
‘This is responsible for fine-detailed vision used for reading, watching TV and recognising people’s faces. It usually affects both eyes but the speed at which it affects each can vary.’
There are two types of the condition: wet and dry. According to Luff, almost all patients start with dry. ‘This is simply wear and tear of the cells of the eye wall upon which the macula sits,’ he says.
‘This usually develops slowly over a number of years. The main symptom is blurring of central vision, usually first experienced as difficulty with reading in poor light.’
Luff says one in ten of those who suffer from dry AMD will go on to develop the wet version. If untreated, this can cause more damage.
‘This is when new blood vessels start growing in the wrong place, causing swelling and bleeding,’ he says. ‘This causes the macula to stop working. No one knows exactly what triggers these vessels to grow but we understand that in AMD the eye produces an excess of the chemical VEGF, which controls blood vessel growth.
‘This chemical causes abnormal vessels to grow, which then leak water. Your central vision is damaged by the presence of this excess fluid.’
Luff says the effects can be limited by monthly injections of anti-VEGF drugs.
If this doesn’t work, there is a relatively new and not widely known therapy called Oraya X-Ray. This is a low-energy X-ray designed to stop the abnormal blood vessels growing, and reduce inflammation and scarring.
‘Only a few patients have had this treatment commercially and it is not yet common medical practice,’ says Luff. ‘However, extensive studies have shown a real benefit in reducing the number of anti-VEGF injections required. And in a small percentage of patients it offers a cure from further leakage.’
Until about ten years ago, there was no treatment for the dry condition but Luff has been involved in a pioneering new surgery for those with a less severe form.
This involves replacing the lens of the eye with two implants that work like a lower power telescope, a gadget known as an intraocular lens for visually impaired people. He now advises on this as well as the latest treatment for severe dry AMD, which involves having a higher-powered, single telescopic implant lens inserted into the eye – known as an implantable miniature telescope.
‘Opticians can provide patients with magnifiers for near and telescopic glasses for distance,’ he says, ‘but these are bulky and difficult to use. However, these telescopic systems improve a patient’s ability to recognise faces, read large print and see something on the TV.’

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