There are many different eye conditions that can impair vision. The effects and severity can also differ with each individual. You may for instance lose central vision or side vision, have patchy or blurred vision, see only light and dark or, rarely, have total loss of sight. Some individuals may have a combination of conditions.
The process may be gradual over many years or sudden; it may be linked to other illness or to injury; it may be inherited; it may vary from day to day; it may or may not be helped by treatment.
It is rare however for sight to fail completely and most people keep some useful vision. Ask your consultant to explain the implications for individual conditions. The Royal National Institute for the Blind (RNIB) produce a series of leaflets on the most common eye conditions, these are available from Bury Society for the blind, the library visual impairment service or RNIB.
Macular degeneration
The macula is that part at the back of the eye concerned with central vision. When the blood vessels there begin to deteriorate, permanent damage can result. Macular disease is caused usually by simply getting older but it can also be linked to diabetes, eye injury, or (rarely) can affect children. As side vision is unaffected there will always be some useful sight. For instance, a bus may be visible but not its number and destination. Activities that need close vision such as reading fine print, needle threading or recognising faces become very difficult if not impossible.
Laser may treat the rarer form of the condition but at present there is no treatment for the more common form.
However, by using appropriate magnifiers and other low vision aids, a lot can be done to make use of any remaining vision.
A very helpful small book, also on tape, called "Coping Again" by Margaret Ford is available from Bury Metro Libraries.
The macular disease society is a support group with a quarterly newsletter. Their address is:
Macular Disease Society,
PO Box 247,
Haywards Heath, RH17 5FF.
Telephone 0800 328 2849 (Freephone Number).
Diabetic retinopathy
This condition, which can eventually affect both insulin-dependent and tablet-treated diabetics, is a major cause of blindness among people of working age. It is characterised by leakage of the blood vessels in the back of the eye and the effects can vary from blurred or spotty vision to serious sight loss.
Laser treatment to seal the haemorrhages can be very helpful, especially if started in the early stages, and for this reason diabetic patients should have an eye examination every year. It has been suggested that the risk of blindness could be reduced by 50% given early treatment.
The British diabetic association issues a magazine in print or on tape and offers much practical advice. Their address is:
British Diabetic Association,
10 Queen Anne Street,
London, W1M 0BD.
Telephone 0207 323 1531.
Glaucoma
There are two kinds of glaucoma, chronic (open-angle) and acute (closed-angle). Both types are associated with raised pressure of the fluid inside the eye, (nothing to do with blood pressure), which damages the optic nerve.
The acute type is the less common and shows itself as a very painful condition, which needs immediate surgical treatment. There may be a build up period of blurred vision, headaches and seeing halos around lights, which should also be attended to promptly.
Chronic glaucoma develops very slowly and painlessly and because of this may not be diagnosed until sight is lost beyond recovery, leaving the patient with tunnel-vision only.
Regular eye-tests are therefore important for everyone, as this may be the only way of discovering that vision is deteriorating. Also as there is often a family history of glaucoma, close blood relatives of anyone with the condition should have their eyes examined annually (the test is free to them).
Glaucoma cannot be cured, nor can sight be restored once lost, but it can be controlled by a regular routine of eye drops, and surgery if necessary.
The international glaucoma association produces information and newsletters. Their address is:
International Glaucoma Association,
King's College Hospital,
Denmark Hill,
London, SE5 9RS.
Telephone 0207 737 3265.
Cataract
Cataract is a clouding of the lens of the eye that causes indistinct vision and poor colour vision, especially in bright sunshine and is the commonest treatable cause of blindness in the UK. Cataracts may occur in addition to other eye conditions such as macular degeneration and treatment for the cataract may not always result in a great improvement in your sight.
Treatment consists usually of replacing the damaged lens with an artificial one; you and the consultant will decide the best stage at which to operate.
Retinitis pigmentosa
This group of diseases is largely inherited and affects the light-sensitive cells in the back of the eye, causing night blindness and tunnel-vision. At present there is little treatment but genetic research is making good progress.
Support, advice and information may be obtained from:
The Retinitis Pigmentosa Society,
PO Box 350,
Buckingham, MK18 5EL.
Tel. 01280 860363.
