The sclera is the tough, fibrous, white outer layer of the eyeball. It's what gives the eye its characteristic white appearance and protects the inner structures of the eye.
Anatomy and Function of the Sclera
The sclera is a crucial part of the eye's anatomy. It extends from the cornea (the clear front part of the eye) to the optic nerve at the back of the eye. Its primary functions include:
- Protection: The sclera acts as a protective barrier, shielding the delicate internal structures of the eye from injury.
- Support: It provides structural support to the eyeball, maintaining its shape and integrity.
- Attachment: It provides an attachment point for the eye muscles, allowing for eye movement.
Several sources corroborate this information:
- Cleveland Clinic: Describes the sclera as the "white of the eye," a tissue layer that covers, protects, and supports the eyeball. https://my.clevelandclinic.org/health/body/22088-sclera
- MedlinePlus: States that the sclera is the "white outer coating of the eye," composed of tough, fibrous tissue. https://medlineplus.gov/ency/article/002295.htm
- American Academy of Ophthalmology: Refers to the sclera as the "outer layer of the eye," the "white" of the eye. https://www.aao.org/eye-health/anatomy/sclera
- National Cancer Institute: Defines the sclera as the "white layer of the eye that covers most of the outside of the eyeball." https://www.cancer.gov/publications/dictionaries/cancer-terms/def/sclera
Conditions Affecting the Sclera
While typically white, changes in the sclera's appearance can indicate underlying health issues. For example:
- Scleritis: Inflammation of the sclera, causing redness, tenderness, and pain. https://www.aao.org/eye-health/diseases/what-is-scleritis
- Scleral Icterus: Yellowing of the sclera, often a sign of jaundice. https://www.osmosis.org/answers/scleral-icterus
- Subconjunctival Hemorrhage: A broken blood vessel in the eye, resulting in a bright red patch on the sclera. https://www.mayoclinic.org/diseases-conditions/subconjunctival-hemorrhage/symptoms-causes/syc-20353826
Understanding the sclera's role in eye health is important for recognizing potential problems and seeking appropriate medical attention.
