Refractive error is a very common eye disorder. It occurs when the eye cannot clearly focus the images from the outside world. The result of refractive errors is blurred vision, which is sometimes so severe that it causes visual impairment.
The four most common refractive errors are:
myopia (nearsightedness): difficulty in seeing distant objects clearly;
hyperopia (farsightedness): difficulty in seeing close objects clearly;
astigmatism: distorted vision resulting from an irregularly curved cornea (the transparent front part of the eye that covers the iris and pupil);
presbyopia: difficulty in focusing on close objects, for example books. It differs from the other disorders in that it is linked to ageing and occurs almost universally.
“640 million people worldwide live with visual impairment due to uncorrected refractive error."
Refractive errors cannot be prevented, but they can be diagnosed by an eye examination and treated with corrective glasses, contact lenses or refractive surgery.
Every year, Vision Aid Overseas utilises the skills of hundreds of optical volunteers who are able to treat thousands of patients by giving them an eye test and correctly prescribed glasses.