The lens' function is to bend and focus light to help you see images clearly.
Because it’s flexible and changes shape, it can help you see objects at varying distances.
As you age, the lens may become weaker or damaged.
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This article explains the structure of the lens and how it works.
The ciliary body produces aqueous humor and bends the lens to refract light.
The lens is held in place by zonular fibers, or zonules, that extend from the ciliary body.
Behind the cornea is the iris, which creates a round aperture called the pupil.
This pupil changes in size to regulate the amount of light that enters the eye.
The crystalline lens sits just behind the iris.
Anatomical Variations
Anatomic variations can exist in the natural lens of the eye.
Many different known and unknown congenital diseases can affect the lens in isolation or as part of a syndrome.
Most often, these congenital defects present in the form of congenital cataracts or clouding of the crystalline lens.
Cataracts at birth can present in one eye (unilaterally) or both eyes (bilaterally).
About one-third of congenital cataract cases are hereditary.
The crystalline lens is a convex lens that creates an inverted image focused on the retina.
The brain flips the image back to normal to create what you see around you.
Conditions That Affect the Lens
As you age, your natural lens also ages.
Presbyopia
When the lens loses elasticity, close-up vision is impacted, resulting inpresbyopia.
This is common for people over age 40.
When this happens, people requirereading glassesor glasses with bifocals to view images clearly up close.
Cataracts
As lenses become clouded, a condition calledcataractsdevelops.
In this procedure, a prosthetic lens called an intraocular lens replaces the cloudy natural lens.
A comprehensive eye exam consists of several different tests that examine the overall health of your eye.
It focuses light that enters the eye and helps you see clearly.
Common conditions associated with the lens include presbyopia and cataracts.
To maintain healthy eyes, see your eye care professional for a comprehensive eye exam.
They can perform a variety of tests to ensure you’re seeing your best.
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