2.7% of children in the US are born with or develop strabismus (crossed eyes) in the early years of life. (The incidence rates are similar in much of the developed world.) While the condition only rarely leads to blindness, it can have long-term impacts on ocular health. Left untreated, one eye will eventually become dominant over the other, heightening the concern over injury or illness in the "good" eye. Strabismus can be treated therapeutically with eye patches, but the success rate isn't optimal. More often, surgical correction is the path chosen not only for cosmetic/social reasons but also because it is more medically effective.