A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z


The dilatation or distention with thinning, particularly of the sclera or cornea.
An eversion of the eyelid.


The condition of vision in which no correction is needed; 20-20 vision.

An inflammation of the inner structures of the eye.


Located on the inner side of the cornea is a very sensitive layer of cells called the ENDOTHELIUM. These cells transfer nutrients from the aqueous humor into the cornea while pumping out waste products and excess water. This is a vital function because if the water content of the cornea is not maintained at precisely the right level, the cornea will become cloudy and can result in a serious reduction in vision. Endothelial cells do not regenerate, so great care must be taken to protect these cells. (see Bullous Keratopathy for more information)

An abnormal recession of the eye into the orbit; also called enophthalmos.
An inversion of the eyelid.
The removal of the eyeball.
The overflow of tears onto the face.

ep' ee skair EYE' tiss

Episcleritis is an acute onset of redness in one or both eyes. There may be a small white "spot" in the middle of the reddened area.

Who can get it?
Episcleritis is seen most commonly in young adults. Women appear to be affected slightly more often than men. In some cases it may be a result of some underlying systemic disease such as rheumatoid arthritis, systemic lupus erythematosus, inflammatory bowel disease, sarcoidosis, gout, herpes or syphillis.

How is it treated?
Most cases of episcleritis will run their course within two to three weeks without treatment. However, patients who are experiencing discomfort may benefit from a regimen of topical anti-inflammatory agents and lubricants.



The EPITHELIUM is the outermost layer of the eye. This includes the cornea, conjunctiva and eyelid.

The tendency of the eyes to deviate medially.


Also Known As: Convergent Strabismus.


A misalignment of the eyes; a condition in which the eyes do not fixate as a pair, but one eye deviates inward, giving them a "crossed" look. While one eye looks straight ahead, the other eye is turned in toward the nose. This inward deviation of the eyes can begin in infancy or later in childhood

esotropia strabismus

Accommodative esotropia is the most common form of esotropia, occuring in farsighted children two years old or older. When a child is young, they can focus their eyes to adjust for the farsightedness but the strain to focus stimulates the eyes to cross. In this case, prescription glasses reduce the focusing effort and can straighten the eyes. Sometimes bifocals are necessary for close work. Eye exercises occasionally help older children.

Pseudoesotropia is the appearance of crossed eyes in which the eyes are actually perfectly aligned in relation to each other. This form of esotropia is common in infants and younger children where the skin on the inner part of the eyelids extends over and covers the inner part of the eye. The white of the eye closest to the nose becomes partially covered, especially when the child looks toward either side, giving the appearance of crossed eyes. However, as the child matures and the facial bones grow, the skin is pulled away from the eye with the growth of the nasal bridge, thereby eliminating the crossed eye appearance.

Acquired Esotropia can have multiple causes. Most common are children who have been farsighted for awhile and have not had glasses, or children who wore glasses but later developed convergence even with the proper glasses.

What are the symptoms?
One eye "turning in" toward the other; both eyes turning inward.

What is the treatment?
Eye exercises can aid in improving eye muscle strength and can resolve some cases of esotropia. . In cases of infants and children, glasses may be prescribed. Eye drops, ointment or special lenses called prisms can also be used to straighten the eyes. Finally, Eye muscle surgery can correct such deviations and restoration of binocular vision is often possible.

The removal of the contents of the eye with retention of the fibrous coat.
Excimer Laser

EX-zih-mer LAY-zuhr

The excimer laser is a new technology used to reshape the front surface of the cornea to treat hyperopia, myopia and astigmatism. It is a "cold" laser that is able to microscopically remove fine layers of corneal tissue, reshaping to correct vision problems. The excimer laser can be used in either the LASIK, LASEK, or PRK techniques.

The removal of the eyeball and all soft tissues within the bony orbit.
The tendency of the eyes to deviate laterally.
An abnormal protrusion of the eyeball; also called exophthalmos.


A misalignment of the eyes; a condition in which one eye deviates outward instead of fixating on the same focal point. See Strabismus, Divergent.

The tilting of the upper part of the vertical meridian of the eye away from the midline of the face.

human eye

Additional keywords and misspellings:
eyeball eye orb globe eyball anatomy eyeanatomy crosssection parts


human eye

The eyes and orbits are protected by reinforced folds of skin called the palpebrae, or eyelid. The eyelids serve three basic functions:

  1. Blinking replenishes and spreads the tear film evenly
  2. Pumps the tears through the lacrimal sac for drainage
  3. Protects the eye from small foregin bodies and excessive light by rapidly and forcefully closing.

The rapid, forceful closure is called reflex blinking. The condition in which the eyes are so closed that they cannot be opened is called lepharospasm.

The space between the lids is called the palpebral fissure and measures approximately 10 mm at its widest point. If the palpebral fissure is too small (i.e. the upper lid droops) the condition is called ptosis.

The Eye Encyclopedia is a collection of eye care terminology created by practicing optometrists and ophthalmologists. The information provided is not intended to be a substitute for regular medical care or to diagnose or treat any medical condition, and should be used only as a supplemental source of information. Please consult your doctor if you have any questions or concerns about your eye health.