The sclera is the white part of the eye.
It is made of tough, fibrous tissue that acts as a protective covering for most of the eyeball.
It surrounds but does not cover the iris, which is the colored part of the eye.
Danny Gabay Photography / Getty Images
Danny Gabay Photography / Getty Images
What does the word “sclera” mean?
The word “sclera” comes from the Greek wordskleros, which means hard.The plural of sclera is sclerae.
What Is the Sclera?
The sclera is the entire visible white exterior of the eye.
The sclera is around 1 mm thick and has four layers:
The sclera is made of collagen fibers.
Collagen is a protein that is also found in your skin, muscles, bones, and connective tissue.
Is the sclera always white?
Certain medical conditions can cause the sclera to change color.
The sclera may become red when it’s irritated.
It may alsoturn yellowin individuals experiencingliver failure.Long-term use of certain medications can cause the sclera to turn blue.
Conditions
Certain medical conditions affect the sclera.
These include:
What is a sclera injection?
A sclera injection is a procedure where medication is injected directly into the sclera.
This may be done as part of the treatment for conditions such as macular degeneration and diabetic retinopathy.
It is the protective covering that runs from the cornea to the optic nerve.
It is made up of fibrous tissue called collagen.
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