Question
Does short-sightedness (myopia) or long-sightedness (hypermetropia) imply necessarily that the eye has partially lost its ability of accommodation? If not, what might cause these defects of vision?
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Answer
No, a person may have normal ability of accommodation yet, he may be myopic or hypermetropic.
In fact, myopia arises when length of eye ball (from front to back) gets elongated and hypermetropia arises when length of eye ball gets shortened.
However, when eye ball has normal length, but the eye-lens losses partially its power of accommodation, this defect is called presbiopia.
In fact, myopia arises when length of eye ball (from front to back) gets elongated and hypermetropia arises when length of eye ball gets shortened.
However, when eye ball has normal length, but the eye-lens losses partially its power of accommodation, this defect is called presbiopia.
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