Cornea of eye - transparent portion of the sclera

Cornea of eye - transparent portion of the sclera - picture

FragmentHealth.com » The Eyes » Cornea of eye - definition

Cornea - the transparent portion of the sclera, the EYE’s outer layer. The cornea functions as a window to allow light to enter the eye and is the first point of refraction (bending lightwaves to focus them on the RETINA). Irregularities in the surface of the cornea can distort refraction, resulting in ASTIGMATISM. Though the cornea has no BLOOD vessels it has numerous NERVE endings that make it highly sensitive. Because it is the outermost portion of the eye, the cornea is also highly vulnerable to injury.

For further discussion of the cornea within the context of ophthalmologic structure and function please see the overview section “The Eyes.”

See also CORNEAL INJURY; CORNEAL TRANSPLANTATION; LENS; REFRACTIVE ERRORS.

Resource: Facts On File Encyclopedia Of Health And Medicine

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