Lions Eye Health Programme
Contents:
> Glaucoma
> Age-related Macular Degeneration (AMD)
Glaucoma
Glaucoma is the name given to a group of eye conditions in which the nerve of sight sustains characteristic damage to the visual field which, if not detected and treated will lead to tunnel vision and eventual blindness. The most common form of the condition is open angle glaucoma.
Open Angle Glaucoma
A watery fluid is naturally produced in the front part of the eye which drains away through a mesh-work of tissues. This fluid nourishes the eye and it's circulation is essential for the health of the eye. However, in glaucoma the drainage system becomes less efficient with the result that the pressure within the eye gradually rises damaging the nerve of sight. It is this pressure which must be controlled in order to prevent permanent damage to the field of vision.
In this country about 2% of people over the age of forty have glaucoma, it is a leading cause of preventable blindness. Although anyone can develop glaucoma, some groups of people are at higher risk than others. These high risk groups include:
- People with a family history of glaucoma
- People of African-Caribbean origin
- People who have diabetes
- People who are very short sighted
At first there are no symptoms, vision appears to be normal, there is no pain or sensation of pressure. As the disease progresses the side vision gradually fails but a person may still be able to read without spectacles. However, the aim of glaucoma screening is to detect the condition before there is any noticeable loss of vision, to prevent its onset.
Glaucoma is usually detected during routine eye test for spectacles, however, it is most important to ensure the optometrist (optician) carries out all three glaucoma tests. Only one test, ophthalmoscopy, (which is an examination of the back of the eye using a special type of torch) is a mandatory part of the sight test. If glaucoma is to be detected at the earliest possible stage then tonometry (a measurement of pressure within the eye) is necessary. Together these tests increase the glaucoma detection rate by four times when compared with ophthalmoscopy alone.
Although angle glaucoma cannot be cured, it can usually be controlled. The most common treatments are:
Medications: these are usually in the form of eye drops. For most people with glaucoma regular use of these eye drops will successfully control the intraocular pressure. However , if a person does not respond well to medical treatment, the eye specialist may alter the medical therapy or suggest laser treatment or surgery to reduce the pressure to an acceptable level.
Laser: during laser treatment a strong beam of light is focused on the drainage area of the eye, this can increase the outflow of fluid from the eye. However, in time the effect of laser treatment tends to wear off and it is likely that glaucoma medication will have to be continued.
Surgery: during an operation the surgeon creates a 'trap door' safety valve to allow excess aqueous fluid to drain more freely thereby reducing the pressure. This is the second most common operation carried out in eye departments in this country and has a high success rate. In some cases medical therapy can be discontinued following surgery although careful monitoring of the intraocular pressure and visual field will still be required for life.
Research
There is an enormous amount of research currently under-way both in this country and overseas including investigation of improved detection techniques, new surgical techniques, and the genetics of glaucoma.
What can you do to protect your vision?
Studies have shown that early detection and treatment of glaucoma, before it causes noticeable visual loss, is the best way to control the disease. If you fall into one of the risk categories for the disease, make sure you have your eyes examined every two years and remember to ask for all three glaucoma tests: Ophthalmoscopy, Tonometry and Perimetry.
For further information on all aspects of glaucoma contact:
International Glaucoma Association
Woodcote House
15 Highpoint Business Village
Henwood
Ashford
Kent TN24 8DH
Tel: 01233 648179
Website: www.glaucoma-association.com
Diabetic Retinopathy
This disease is a leading cause of blindness among people of working age in Britain. It is caused by changes in the blood vessels of the retina. In some people with diabetic retinopathy, retinal blood vessels may swell and leak fluid. In other people, abnormal new blood vessels grow on the surface of the retina. These changes may result in visual loss or blindness.
Who is most likely to get Diabetic Retinopathy?
Anyone with diabetes. The longer someone has diabetes, the more likely he or she will get diabetic Retinopathy. Over half of all people with diabetes will develop some degree of Retinopathy during their lifetime.
What are its symptoms?
Often there are none in the early stages of the disease. Vision may not change until the disease becomes severe. Nor is there any pain.
Blurred vision may occur when the macula - the part of the retina that provides sharp, central vision - swells from the leaking fluid. This condition is called Macular Oedema. If new vessels have grown on the surface of the retina, they can bleed into the eye, blocking vision. But, even in more advanced cases, the disease may progress a long way without symptoms. That is why regular eye examinations for people with diabetes are so important.
How is it detected?
If you have diabetes, you should have your eyes examined at least once a year. Your eyes should be dilated during the examination. That means eye-drops are used to enlarge your pupils. This allows the eye care professional to see more of the inside of your eyes to check for signs of disease.
Can Diabetic Retinopathy be treated?
Yes. Your eye care professional may suggest laser treatment in which a strong light beam is aimed onto the retina to shrink the abnormal vessels. Laser treatment has been proved to reduce the risk of severe visual loss from diabetic Retinoptahy in 80%-90% of people.
If you have a Macular Oedema, laser surgery may also be used. In this case the laser beam is used to seal the leaking blood vessels.
However, laser surgery often cannot restore vision that has already been lost. That is why finding diabetic Reinopathy early is the best way to prevent visual loss.
How common are the other diabetic diseases?
If you have diabetes, you are also at risk of other diabetic eye diseases. Studies show that you are twice as likely to get a cataract as a person who does not have the disease. Also, cataracts develop at an earlier age in people with diabetes. Cataracts can usually be treated by surgery.
Glaucoma may also become a problem. A person with diabetes is nearly twice as likely to get glaucoma as another adult. And, as with diabetic Retinopathy, the longer you have had diabetes, the greater your risk of getting Gluacoma.
What research is begin done?
Much research is being done to learn more about diabetic eye disease. Diabetes UK is supporting a number of research studies in the laboratory and with patients Retinopathy and how it can be better treated. This research should provide better ways to detect and treat diabetic eye disease and prevent blindness in more people with diabetes.
What can you do to protect your vision?
Finding and treating the disease early, before it causes visual loss or blindness, is the best way to control diabetic eye disease. So, if you have diabetes, make sure you get a dilated eye examination at least once a year.
For further information on all aspects of diabetes contact:
Diabetes UK
Macleod House
10 Parkway
London NW1 7AA
Tel 020 7424 1000
Website: www.diabetes.org.uk
Age-Related Macular Degeneration (AMD)
Age Related Macular Degeneration is a major cause of vision loss in people over 60. Cells in the macula at the back of the retina breakdown causing loss of sight in the central part of the field of vision; some peripheral vision remains, but the loss of detailed vision causes severe upsets in the quality of life - such as recognising people, reading, watching television and driving.
What types of AMD are there?
Dry AMD is the more common form of the disease, about 60% of cases. It is caused by slow decay and disintegration of the cells of macula. Sadly there is currently no treatment for Dry AMD.
Wet AMD is the other type, accountable for 40% of cases - called Wet because of the leakage of blood vessels on the retina causing scarring and damage to the macula. Some forms of Wet AMD can be treated if detected early.
How many people in the UK might have AMD?
Macular degeneration is the leading cause of severe sight loss among people over 60 in the UK.
It is estimated that macular degeneration affects up to 500,000 people in the UK.
What are the risk factors for AMD?
Although the cause of macular disease is not fully understood, scientists believe that a combination of factors may predispose someone to the disease.
Age is the main risk factor - as you grow older your risk of developing AMD increases
Diet and nutrition - a low intake of antioxidants, a high fat diet or excessive alcohol may increase the risk of developing the disease
Smoking - is a major risk factor and can lead to eye damage
Women - are more prone to the condition than men. A woman over 70 has double the chance of developing AMD compared to a man of the same age
Genetics - may be significant and it is believed that people with a family history of AMD have an increased change of developing the condition themselves.
How is AMD detected - what are the symptons?
If you suspect something is wrong and straight lines look wavy, there is a bit of missing or blurred vision, you should visit an Optometrist who is qualified to examine your eyes thoroughly. The Optometrist can now refer you direct to the eye clinic. Ask him for an 'Amsler Grid' for home use so you can keep a check on your sight, if you think you may be vulnerable.
Can AMD be treated?
You need to establish if you have the 'Dry' form or the 'Wet'.
There is no treatment for Dry but there is the possibility that diet supplementation may slow progression down. The more severe form, Wet AMD may be suitable for laser treatment including pho dynamic therapy (PDT). Other new treatments are under development.
Living with AMD
AMD patients retain peripheral vision and do not go completely blind. A range of low vision aids is available to maximise remaining vision. The RNIB and local associations for the blind display and sell magnifiers and other aids to living. Hi tech CCTV readers are extremely helpful. Social Services arrange low vision assessments for people registered partially sighted.
What research is being done?
Research continues into many areas of AMD including nutrition, genetics, cell therapy, pharmacological and laser treatments and development of low vision equipment.
For more information contact:
The Macular Disease Society
13A Bridge Street
Andover
Hampshire SP10 1BE
Tel: 01264 350551
Website: www.maculardisease.org
Low Vision
Being diagnosed as having sight defects that cannot be rectified and that have left you with low vision must be one of the most traumatic times for anyone. Sight is so important to live a normal life and any form of low vision will make living more difficult.
However there are nearly 2 million people in the UK nowadays who have low vision and the majority of these live reasonable lives with the aid that is available.
Help comes in two forms:
Firstly, there are the local societies that cover most of the country. They vary a great deal in both scale and scope of the support they can offer.
Many are simply run and manned by volunteers, but some local societies are much bigger and offer far greater support.
In many cases the volunteers have low vision themselves and are a good example of what can be achieved. They often try to be on hand when Low Vision is first diagnosed.
The societies are a good source of lay advice and, if they do not have the answers, will know where to go to obtain them.
The second type of help is the physical one. Nowadays thanks in many instances of computer developments, there are aids to do most tasks in one form or another. They help with reading and needlework, playing games and cards and with everyday tasks such as telling the time, cutting nails and making telephone calls, etc.
When you know you have Low Vision that cannot be corrected your first action should be to contact your local society for the visually impaired, if they have not already contacted you. If you cannot find a local contact easily then ring NALSVI. Depending on your condition it is likely that your local Social Services should be in a position to offer advice and supply aids to help keep you independent, although they vary a great deal from one county to another. The degree of help may depend on your personal circumstances and the degree of your visual impairment.
For more information contact:
NALSVI
PO Box 823
Doncaster
S Yorkshire DN1 9QA
Tel: 01302 571888
Website: www.nalsvi.cswebsites.org
or
RNIB - Low Vision
58-72 John Bright Street
Birmingham B1 1BN
Tel: 0845 766 9999
Website: www.rnib.org.uk
