10 doctors weighed in:
What causes short sightedness?
10 doctors weighed in

Dr. Robert Chang
Ophthalmology
7 doctors agree
In brief: Genetics+environment
Myopia, in a simple model, depends on refractive index of cornea-tear film, lens, length of eye.
So if any of these are altered so that the image focuses in front of the retina (steep k, longer eye, higher refractive lens index, etc.), then you become short sighted. The anatomy of the eye is inherited and a lot of near work can affect it.

In brief: Genetics+environment
Myopia, in a simple model, depends on refractive index of cornea-tear film, lens, length of eye.
So if any of these are altered so that the image focuses in front of the retina (steep k, longer eye, higher refractive lens index, etc.), then you become short sighted. The anatomy of the eye is inherited and a lot of near work can affect it.
Dr. Robert Chang
Dr. Robert Chang
Thank
Dr. Andrew Shatz
Ophthalmology
4 doctors agree
In brief: The eye's shape
Shortsightedness (nearsightedness, myopia) is a result of the shape of the eye.
When an eye is longer or the cornea (front window) has a steeper curve than usual, light entering the eye comes to a focus in front of the retina (film layer). As you get closer to an object, the retina is brought closer to the focus point, hence the term "nearsighted".

In brief: The eye's shape
Shortsightedness (nearsightedness, myopia) is a result of the shape of the eye.
When an eye is longer or the cornea (front window) has a steeper curve than usual, light entering the eye comes to a focus in front of the retina (film layer). As you get closer to an object, the retina is brought closer to the focus point, hence the term "nearsighted".
Dr. Andrew Shatz
Dr. Andrew Shatz
Thank
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