A cataract is the development of haziness or opacity in the lens of the eye. Early changes in lens clarity may have no noticeable effect on the vision, whilst a 'mature' cataract will reduce the vision to a level of blindness. Cataracts are indeed the world's leading cause of blindness.
Causes of Cataract
In the UK the majority of patients with cataract are in the older age groups and the progressive changes in lens clarity can be assumed to be an age-related deterioration in the function of the cells forming the lens of the eye. Many factors can affect the formation of lens opacities - cataracts are even found in some infants and this is often linked to infection or metabolic disease. Diabetes is an important metabolic condition which can cause cataracts in adults. Diarrhoea, dehydration, malnutrition and high levels of ultra-violet and infra-red radiation may all play a part in causing cataracts to form at an earlier age in countries where these conditions are prevalent. Cataracts are also seen following trauma to the eye.
Treatment of Cataract
Cataract extraction is now generally carried out using the procedure of phako-emulsification.