Surgery that corrects visual acuity, with the objective of reducing or eliminating the need for glasses and contacts. Includes radial keratotomy, PRK, LASIK, and corneal implants.

How often you discard and replace your contact lenses: every day, week or two weeks (disposable); or every month, two months or calendar quarter (frequent replacement). It's important to differentiate between replacement schedule

The sensory membrane that lines the eye; it is composed of several layers and functions as the immediate instrument of vision by receiving images formed by the lens and converting them into signals which reach the brain by way of the optic ner

Condition where the retina separates from the choroid.

Condition characterized by the progressive loss of peripheral vision, usually beginning with night blindness.

Type of contact lens made of breathable plastic that is custom-fit to the shape of the cornea. RGPs are the successor to old-fashioned hard lenses, which are now virtually obsolete.

Surgical procedure where cuts are made in the cornea in a radial pattern, to flatten the cornea and correct myopia.

A photosensitive receptor in the retina that helps you to see in low light.

The outer coat of the eyeball that forms the visible white of the eye and surrounds the optic nerve at the back of the eyeball. segment A part, as in the near-vision portion of a pair of bifocals.

Contacts made of gel-like plastic containing varying amounts of water.

Products used to clean, disinfect and store contact lenses.

Number representing the amount of sun something blocks. For example, if you normally begin to burn after half an hour in the sun, a sunscreen with an SPF of 2 should let you stay out twice as long (1 hour), SPF 4 should le

A contact lens design that is like a sphere and is fairly common; in contrast, toric lenses for astigmatism are football-shaped and are less common.

Small, cloudy specks in the eye that become noticeable when they fall in the line of sight.

Type of hinge on eyeglass frames that is more flexible than a regular hinge, making the frames more durable.

A misalignment of the eyes: they don't point at the same object together. Crossed eyes are one type of strabismus.

The cornea's middle layer; it consists of lamellae (collagen) and cells, and makes up most of the cornea.

A blocked gland at the edge of the lid which has become infected by bacteria.

Part of the eye that holds the lens in place.

The "arm" of a pair of glasses, running from the ear to the lens area. titanium A type of metal alloy that is very strong. Eyeglasses made of titanium are lightweight and durable and often hypo-allergenic.

A lens design with two different optical powers at right angles to each other for the correction of astigmatism.

A lens design that has three focal areas: a lens for close work or reading, a lens for mid-distance viewing or arm's length, and a lens for faraway viewing or driving.

The invisible part of the light spectrum whose rays have wavelengths shorter than the violet end of the visible spectrum and longer than X rays. UVA and UVB light are harmful to your eyes and skin.

Part of the eye between the lens and the retina, containing a clear jelly called the vitreous humor.

How long you wear your contact lenses: either daily wear (you remove the lenses each night) or extended wear (you may sleep with them in). It's important to differentiate between wear schedule and replacement schedule - that is, how oft