Lazy eye, or amblyopia, develops when the brain and one eye don't work together properly. The brain fails to recognize the sight from the affected eye, leading it to favor the stronger eye. Over time, vision in the weaker eye deteriorates because the brain increasingly relies on the stronger eye's input. This is often referred to as "lazy eye" because the stronger eye does most of the work.
Causes of Lazy Eye
Amblyopia typically emerges from birth to age 7, a crucial period for eye and brain development. Several factors can contribute:
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Unequal visual input: A significant difference in vision quality between the two eyes (e.g., one eye being significantly more nearsighted or farsighted than the other) prevents proper brain development and can lead to a preference for the better-seeing eye.
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Strabismus (Misaligned Eyes): When the eyes don't point in the same direction (crossed eyes or wall-eyes), the brain receives conflicting signals, causing it to suppress input from one eye to avoid double vision. This suppression ultimately leads to amblyopia.
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Cataracts or other eye conditions: Conditions like cataracts (clouding of the eye's lens), ptosis (droopy eyelid), or refractive errors (nearsightedness, farsightedness, astigmatism) can also obstruct clear vision in one eye, leading to the brain favoring the other eye.
Amblyopia usually affects only one eye, but rarely both. Early detection and treatment are crucial as it can lead to permanent vision loss if left untreated. The brain's ability to fully integrate input from both eyes significantly reduces during childhood, making early intervention vital.
