Amblyopia (or lazy eye) occurs when vision in one of the eyes is reduced because the eye and the brain are not working together properly. Amblyopia is the most common cause of visual impairment in childhood. It affects about 2% of adolescents. Amblyopia usually develops before the age of 6 and can persist for life if untreated. It causes more vision loss than trauma and all other ocular diseases.
Astigmatism is a very common vision problem caused by an irregularly shaped cornea. Blurred vision at all distances is the most significant indicator of astigmatism and many people who have astigmatism also have myopia or hyperopia. It is often present at birth. Family history of the condition increases risk.
Strabismus is when eyes are turned in, turned out or not working as a team. It affects up to 5 percent of all children to some degree and can begin during infancy. Signs and symptoms include wandering eye, double vision, vision in only one eye and eyes that appear crossed.