The sclera, or white of the eye, is strong tissue that wraps around the eyeball. It helps maintain your eyeball’s shape and protects it from injury. Several things can make the entire sclera change color or cause spots of color. Many scleral conditions resolve on their own in a few weeks, but some require medical attention.
The sclera, or white of the eye, is a protective covering that wraps over most of the eyeball. It extends from the cornea in the front to the optic nerve in the back.
This strong layer of tissue, which is no more than a millimeter thick, gives your eyeball its white color. It also protects and supports your eye. The plural for sclera is sclerae.
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The sclera functions as the supporting wall of the eyeball. It helps maintain your eyeball’s shape, and protects it from injury.
The sclera is covered by conjunctiva, which are clear mucus membranes that lubricate (moisturize) your eye. Muscles attached to the sclera help move your eyeball up and down and side to side.
The sclera is made of tough collagen fibers, which crisscross in random directions. That random pattern gives your eyeball its white color and gives the sclera strength. This contrasts with the collagen fibers in your cornea, which are very organized and allow the cornea to be clear.
The sclera has four layers, from the outside to the inside:
Several things can cause the entire sclera to change color or spots of color to appear:
Other problems with the sclera include:
Minor injury or inflammation of the sclera often heals in a few days or weeks. But if you have any other symptoms or the problem doesn’t go away, talk to your healthcare provider or ophthalmologist. An ophthalmologist specializes in disorders and diseases of the eyes.
You can help protect your sclerae from injury with several simple strategies:
Talk to your healthcare provider if you notice anything different in your sclera, such as:
A note from Cleveland Clinic
The sclera is a protective covering that wraps over most of your eyeball. It supports your eyeball and forms the white of your eye. If you experience color changes in the whites of your eyes, especially with pain or vision changes, call your healthcare provider immediately.
Last reviewed by a Cleveland Clinic medical professional on 11/12/2021.
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