In this section, you will learn about the most common eye conditions. Knowing how sight loss affects different people with different conditions is important to understanding the challenges that blind and partially sighted people face.
For more information on different eye conditions please click here https://www.fightforsight.org.uk/about-the-eye/a-z-eye-conditions/
Albinism is a comparatively rare genetically inherited group of conditions which results in a reduction or complete lack of pigment (colour) in the skin, hair and eyes of people with the condition. This can result in pale skin which burns easily in the sun, virtually white hair, very severe short-sight and photophobia (a severe sensitivity to light).
Age-related macular degeneration (AMD) is an eye condition that affects a tiny part of the retina at the back of your eye, which is called the macula. AMD causes problems with your central vision, but does not lead to total loss of sight and is not painful. AMD affects the vision you use when you’re looking directly at something, for example when you’re reading, looking at photos or watching television. AMD may make this central vision distorted or blurry and, over a period of time, it may cause a blank patch in the centre of your vision.
Cataracts are a very common eye condition. As we get older the lens inside our eye gradually changes and becomes less transparent (clear). A lens that has turned misty, or cloudy, is said to have a cataract. Over time a cataract can get worse, gradually making your vision mistier. A straightforward operation can usually remove the misty lens and replace it with an artificial lens to enable you to see more clearly again.
This information is about cataracts in adults. Some children develop cataracts, called congenital cataracts, before or just after birth but these are usually dealt with in a different way to cataracts in adults.
Charles Bonnet syndrome (CBS) is a common condition among people who have lost their sight. It causes people who have lost a lot of vision to see things that aren’t really there, known as visual hallucinations.
CBS can be distressing, but the hallucinations are usually not permanent. People who have CBS may have lost a lot of their vision from an eye condition, such as age-related macular degeneration, cataracts or diabetic retinopathy. Many of these conditions are more common in older people so many people who have CBS are older. However, anyone of any age, including children, may develop this condition as any eye condition that causes sight loss can trigger CBS. There are thought to be more than 100,000 cases of CBS in the UK. Some research suggests that up to 60% of individuals who are experiencing serious sight loss may develop it.
Diabetes can affect your eye in a number of ways: The most serious eye condition associated with diabetes involves the network of blood vessels supplying the retina. This condition is called Diabetic Retinopathy.
The unusual changes in blood sugar levels resulting from diabetes can affect the lens inside the eye, especially when diabetes is uncontrolled. This can result in blurring of vision which comes and goes over the day, depending on your blood sugar levels.
A longer term effect of diabetes is that the lens of your eye can go cloudy, this is called a cataract.
Not everyone who has diabetes develops an eye complication. Of those that do, many have a very mild form of retinopathy which may never progress to a sight threatening condition.
The most serious complication of diabetes for the eye is the development of diabetic retinopathy. Diabetes affects the tiny blood vessels of the eye and if they become blocked or leak then the retina and possibly your vision will be affected. The extent of these changes determines what type of diabetic retinopathy you have. Forty per cent of people with type 1 diabetes and twenty per cent with type 2 diabetes will develop some sort of diabetic retinopathy.
Background Diabetic Retinopathy
This is the most common type of diabetic retinopathy and many people who have had diabetes for some time will have this early type. The blood vessels in the retina are only very mildly affected, they may bulge slightly (micro aneurysm) and may leak blood (haemorrhages) or fluid (exudates). As long as the macula is not affected, vision is normal and you will not be aware that anything is wrong. Your retinal screening test will keep a close check on these early changes and ensure that any signs of progression to more serious stages of retinopathy are detected early.
Glaucoma is the name given to a group of eye conditions which cause optic nerve damage and can affect your vision. Glaucoma damages the optic nerve at the point where it leaves your eye; this damage may be caused by raised eye pressure. In most cases, high pressure and weakness in the optic nerve are both involved to a varying extent. (Eye pressure is not connected to your blood pressure). Your eye needs a certain amount of pressure to keep the eyeball in shape so that it works properly. However, if the optic nerve comes under too much pressure then it can be damaged.
Nystagmus is a continuous uncontrolled to and fro movement of the eyes. The movements may be in any direction. This means that the eyes will look like they are moving from side to side or up and down or even in circles. Most people with Nystagmus have reduced vision.
Retinitis pigmentosa is the name given to a diverse group of inherited eye disorders. These eye conditions affect a part of your eye called the retina. RP causes permanent changes to your vision but how quickly this happens and how it changes differs between people. These changes may include difficulty with vision in dim light or the dark and the loss of your side or peripheral vision. If you have RP, sight loss is gradual but progresses over a period of many years.