Deprivation Myopia and Emmetropization
We pointed out in Chapter 6 that the eyeball grows in most people to be the correct size for the image to be in focus on the retina. This process is called emmetropization. Many infants are born hyperopic, and become emmetropic by 2–3 years of age. Some are born emmetropic and become myopic with age; that is, their eyeballs are too large for the power of the lens and the cornea, so that the image falls in front of the retina. A few are born myopic, and this is a condition that needs to be reversed early, because the eyeball can grow, but it cannot shrink.
KeywordsVasoactive Intestinal Peptide Refractive Error Tree Shrew Focus Image Visual Deprivation
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