How is the eye protected?

The eyelashes and eyelid protect the eye from dust, dirt and sand particles. The blink reflex is the body's quick response to anything touching the eye. In a blow to the face, the bony structure often prevents trauma to the eye itself. 
Laura C. Fine, MD
Despite its reputation as a delicate organ, the eye is remarkably resilient and hardy, engineered by nature to last from infancy through old age. Shaped like a sphere, the eyeball is about an inch in diameter, with a slight protrusion in front. It sits in a bony, protective socket of the skull, called the orbit, and is surrounded by a cushiony layer of fat, fibrous tissue, and muscles.

Eyelids and eyelashes act like windshield wipers, constantly brushing and blinking away dust and other debris that might otherwise blow into the eye. The lachrymal gland, located behind the upper lid, produces tears that course over the eye surface and keep it lubricated, nourished, and clear of foreign matter. Tears drain off into the nose through ducts at the eye's innermost corner.

The conjunctiva is a thin, colorless membrane that lines the inner surfaces of the eyelids and the front portion of the sclera, the eye's white outer surface. The conjunctiva is so sensitive that when it becomes aware of a foreign body, it automatically triggers a protective reaction, such as tearing or blinking.

The eyeball is surrounded by ligaments, fat, and muscles and rests in a protective, bony socket called the orbit. The cornea, a tough, transparent dome that helps focus light, and the sclera, the white portion of the eye, protect the interior of the eye. The optic nerve delivers visual information to the brain.

Three distinct layers of tissue surround the eye and form its wall. The surface layer (approximately 1 millimeter thick) is made of tough collagen. You see it in the visible part of the eyeball as both the sclera (the white part) and the cornea, a clear, domelike window at the front of the eye.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.