A cataract is a clouding of part of the eye called the lens. Vision becomes blurred or dim because light cannot pass through the clouded lens to the back of the eye.Cataracts can form at any age, but most often in older people. In younger people they can result from injury, certain drugs, long-standing inflammation or illnesses such as diabetes. They can be treated through surgery.
Glaucoma is characterised by raised pressure inside the eye, which can damage the optic nerve, reducing the field of vision and the ability to see clearly. Early detection is vital, as lost vision cannot be regained, but treatment can prevent furthervision loss.
Hypertension or high blood pressure leads to many changes in the blood vessels of the body. These same changes in blood vessels affect the eyes in many ways. It can cause painless but severe loss of vision in the eye. Many of the ocular conditions caused by hypertension may not have any symptoms in the initial stages. Therefore it is important to have a periodic eye check-up to detect these.
Diabetes can affect the eye in a number of ways. These usually involve the fine network of blood vessels in the retina. Although vision may be good, changes can be taking place to the retina that need treatment. And because most sight loss in diabetes is preventable, early diagnosis is vital. Have an eye examination every year! Do not wait until the vision has deteriorated to have an eye test.
At the centre of the retina is the macula, a small area about the size of a pinhead. This is the most specialised part of the retinaand it is vital as it enables you to see fine detail and read small print. Sometimes the delicate cells of the macula become damaged and stop working. We do not know why this is, although it tends to happen as people get older (~60+). This is called age-related macular degeneration (ARMD). As more people delay retirement and continue working, central vision loss due to ARMD must be borne in mind.