There are crucial aspectsregarding the subjects of amblyopia and strabismus which are important toemphasize. If it is obvious that your child has an eye turn, then it should beclear that you must take him to be evaluated by a professional who can make anoptimal assessment. You cannot know if amblyopia is present just byobservation. From an aesthetics point of view, for an eye turn to beobservable, the deviation must exceed 15-20 prism diopters, or approximately12-15°.
Therefore,if the eye examination is brief and only evaluates visual acuity and arefractive measurement for glasses (which unfortunately is frequently thecase), then the examination is inadequate. If a very careful assessment ofbinocularity, or eye teaming is not performed, many cases of amblyopia andsmall amounts of strabismus are often missed.
Thisis also true in the area of learning problems. As one of my main areas ofinterest is learning problems, I ask the following question, “How many cases ofchildren diagnosed with dyslexia, attention deficit, or simply learningproblems have, as the root of their troubles, problems in binocularity whichare undiscovered because of an inadequate vision examination?” We will delve intothis more in Chapter 19.
（文章摘自: CROSSED & LAZY EYES MYTHS,MISCONCEPTIONS AND TRUTHS）