In later years I looked at the figures for those presenting at the NOOR Eye Institute in Kabul in one year. The needs are very great. In the early 1970s the World Health Organisation realised that there were more than 70 definitions of blindness in UN member states. The following figures are estimates. So much could be said about these different causes of blindness.
Cataract requires skilled surgeons to provide operative care, now with intraocular lens implants.
Glaucoma is often difficult to diagnose in the early stages. Trachoma, the most important infective cause, has decreasing prevalence worldwide, as hygiene and public awareness improves. Vitamin A deficiency in children may lead to corneal scarring in those who survive. There is an epidemic of diabetes around the world and the sight-saving laser involves considerable costs. It is estimated that around 45 million people are blind in the world by WHO definition and a further 135 million are visually impaired.