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Any sudden problem with the eye or change in vision requires prompt medical attention.
Vision is a complex process that involves many different parts of the eye. Light first passes through an outer layer of the eye called the cornea, next travels through an opening in the eye called the pupil, and then passes through the lens of the eye. The colored part of the eye, called the iris, has muscles that control the size of the pupil. Like the lens of a camera, these parts of the eye help focus and control the amount of light that enters the eye. The retina, lining the inside back wall of the eye, has cells that are sensitive to light and acts like the light-sensitive back of a camera, where the visual images first begin to be detected or “developed.” Information from the retina eventually reaches the brain, where it is further processed and understood.
Muth CC. Eye Emergencies. JAMA. 2017;318(7):676. doi:10.1001/jama.2017.9899
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