Click Here to access our office online
.
(Excerpted from Dictionary of Eye Terinology © 1990-2003 by Triad Communications)
ACCOMMODATION - The ability of the eye to change its focus from distant to near objects; process achieved by the lens changing its shape.
ANTERIOR CHAMBER - The space in front of the iris and behind the cornea.
AQUEOUS HUMOR, AQUEOUS FLUID - (A-kwe-us) - Clear, watery fluid that flows between and nourishes the lens and the cornea; secreted by the ciliary processes.
ASTIGMATISM - (uh-STIG-muh-tizm) - A condition in which the surface of the cornea is not spherical; causes a blurred image to be received at the retina.
BLIND SPOT - (1) A small area of the retina where the optic nerve enters the eye; occurs normally in all eyes. (2) Any gap in the visual field corresponding to an area of the retina where no visual cells are present; associated with eye disease.
CENTRAL VISION - See VISUAL ACUITY.
CHOROID (KOR-oyd) - The layer filled with blood vessels that nourishes the retina; part of the uvea.
CILIARY MUSCLES - The muscles that relax the zonules to enable the lens to change shape for focusing.
CILIARY PROCESSES - The extensions or projections of the ciliary body that secrete aqueous humor.
CONES, CONE CELLS - One type of specialized light-sensitive cells (photoreceptors) in the retina that provide sharp central vision and color vision. Also see RODS.
CONJUNCTIVA - (KAHN-junk-TY-vuh) - The thin, moist tissue (membrane) that lines the inner surfaces of the eyelids and the outer surface of the sclera.
CONTRAST SENSITIVITY - The ability to perceive differences between an object and its background.
CORNEA - (KOR-nee-uh) - The outer, transparent, dome-like structure that covers the iris, pupil, and anterior chamber; part of eye's focusing system.
DILATION - A process by which the pupil is temporarily enlarged with special eye drops (mydriatic); allows the eye care specialist to better view the fundus.
FUNDUS - The interior lining of the eyeball, including the retina, optic disc, and macula; portion of the inner eye that can be seen during an eye examination by looking through the pupil.
HYPEROPIA - (hy-pur-OH-pee-uh) - Farsightedness; ability to see distant objects more clearly than close objects; may be corrected with glasses or contact lenses.
INTRAOCULAR PRESSURE (IOP) - Pressure of the fluid inside the eye; normal IOP varies among individuals.
IRIS - The colored ring of tissue suspended behind the cornea and immediately in front of the lens; regulates the amount of light entering the eye by adjusting the size of the pupil.
LACRIMAL GLAND - (LAK-rih-mul) - The small almond-shaped structure that produces tears; located just above the outer corner of the eye.
LENS - The transparent, double convex (outward curve on both sides) structure suspended between the aqueous and vitreous; helps to focus light on the retina.
LEGAL BLINDNESS - In the U.S., (1) visual acuity of 20/200 or worse in the better eye with corrective lenses (20/200 means that a person must be at 20 feet from an eye chart to see what a person with normal vision can see at 200 feet) or (2) visual field restricted to 20 degrees diameter or less (tunnel vision) in the better eye.
MACULA - (MAK-yoo-luh) - The small, sensitive area of the central retina; provides vision for fine work and reading.
MYOPIA - (my-OH-pee-uh) - Nearsightedness; ability to see close objects more clearly than distant objects; may be corrected with glasses or contact lenses.
OPTIC CUP - The white, cup-like area in the center of the optic disc.
OPTIC DISC/OPTIC NERVE HEAD - The circular area (disc) where the optic nerve connects to the back part of the retina.
OPTIC NERVE - The bundle of over one million nerve fibers that carry visual messages from the retina to the brain.
PERIPHERAL VISION - (per-IF-ur-al) - Side vision; ability to see objects and movement outside of the direct line of vision.
POSTERIOR CHAMBER - The space between the back of the iris and the front face of the vitreous; filled with aqueous fluid.
PRESBYOPIA - (prez-bee-OH-pee-uh) - The gradual loss of the eye's ability to change focus (accommodation) for seeing near objects caused by the lens becoming less elastic; associated with aging; occurs in almost all people over age 45.
PUPIL - The adjustable opening at the center of the iris that allows varying amounts of light to enter the eye.
RETINA - (RET-in-nuh) - The light-sensitive layer of tissue that lines the back of the eyeball; sends visual impulses through the optic nerve to the brain.
RETINAL PIGMENT EPITHELIUM - (RPE) (ep-ih-THEE-lee-um) - The pigment cell layer that nourishes the retinal cells; located just outside the retina and attached to the choroid.
RODS, ROD CELLS - One type of specialized light-sensitive cells (photoreceptors) in the retina that provide side vision and the ability to see objects in dim light (night vision). Also see CONES.
SCHLEMM'S CANAL - The passageway for the aqueous fluid to leave the eye.
SCLERA - (SKLEH-ruh) - The tough, white, outer layer (coat) of the eyeball; with the cornea, it protects the entire eyeball.
TRABECULAR MESHWORK - (truh-BEC-yoo-lur) - The spongy, mesh-like tissue near the front of the eye that allows the aqueous fluid (humor) to flow to Schlemm's canal then out of the eye through ocular veins.
UVEA, UVEAL TRACT - (YOO-vee-uh) - The middle coat of the eyeball, consisting of the choroid in the back of the eye and the ciliary body and iris in the front of the eye.
VISUAL ACUITY - The ability to distinguish details and shapes of objects; also called central vision.
VISUAL FIELD - The entire area that can be seen when the eye is forward, including peripheral vision.
VITREOUS - (VIT-ree-us) - The transparent, colorless mass of gel that lies behind lens and in front of retina.
ZONULES - (ZAHN-yoolz) -The fibers that hold the lens suspended in position and enable it to change shape during accommodation.
Back to our Medical Information page
Home I About Us I Assistive Technology I Bookstore I Contact Us I Coping Tips I Education I FAQ I Fundraising I Jobs I Library I Links I Medical I News I People I Press Releases I Services I Site Index I Volunteer Opportunities I Search I Talk To Office I