Glaucoma is the name given to a group of eye conditions where the optic nerve is damaged at the point where it leaves the eye. The optic nerve carries images from the retina, the light sensitive membrane attached to the inner surface of the eye, to the brain.
There are four main types:
Chronic glaucoma (slow onset)
Acute glaucoma (sudden onset)
Secondary glaucoma (caused by another eye condition)
Congenital or developmental glaucoma (a condition in babies caused by malformation of the eye)
The risk of glaucoma increases with age and if left untreated it can cause blindness.
Chronic glaucoma often has no symptoms and the eye may seem normal. This isn't painful and at first your vision may be unaffected.
Common symptoms of Glaucoma are:
Hazy or blurred vision
The appearance of rainbow-colored circles around bright lights
Severe eye and head pain
Nausea or vomiting (accompanying severe eye pain)
Sudden sight loss
A cataract is a clouding of the lens in your eye and can develop in one or both eyes. The lens is normally clear and sits behind the iris – the coloured part of the eye. The lens helps focus light to produce a sharp image on to the retina at the back of the eye and changes shape to allow you to see close objects. A cataract acts like a frosted glass coating that scatters light, causing blurring and lack of clarity.
Cataracts are painless and usually cause a gradual worsening of sight.
The main symptoms are:
Blurring
Dazzled by lights
Double vision
Changes in color vision
You should have your eyes checked regularly - at least every two years. However, those suffering from Glaucoma or diabetes may need their eyes tested and checked more regularly. If you start to suffer from headaches, double vision or blurred vision, or experience any abnormality in your vision an immediate eye test is advisable.
Spots or floaters are small, semi-transparent or cloudy particles within the vitreous. They appear as specks of various shapes and sizes, threadlike strands or cobwebs. They move as your eyes move and seem to dart away when you try to look at them directly. They can result from deterioration of the vitreous fluid due to aging or from certain eye diseases or injuries. Most spots are not harmful and rarely limit vision. But, spots can be indications of more serious problems.
Diabetic eye disease refers to a group of eye problems that people with diabetes may face as a complication of this disease. All can cause severe vision loss or even blindness.
Diabetic eye disease includes:
Diabetic retinopathy: Damage to the blood vessels in the retina.
Cataract: Clouding of the lens of the eye.
Glaucoma: Increase in fluid pressure inside the eye that leads to optic nerve damage and loss of vision.
Diabetic retinopathy. This disease is a leading cause of blindness in American adults. 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 vision loss or blindness.
There are often no symptoms in the early stages of diabetic retinopathy. There is no pain and vision may not change until the disease becomes severe. 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 edema. If new vessels have grown on the surface of the retina, they can bleed into the eye, blocking vision. Even in more advanced cases, the disease may progress a long way without symptoms. This symptomless progression is why regular eye examinations for people with diabetes are so important.
Anyone with diabetes. The longer someone has diabetes, the more likely he or she will get diabetic retinopathy. Between 40-45 percent of those with diagnosed diabetes have some degree of diabetic retinopathy.
If you have diabetes, you should have your eyes examined at least once a year. Your eyes should be dilated during the exam, which means eye drops are used to enlarge your pupils. This dilation allows the eye care professional to see more of the inside of your eyes to check for signs of the disease.