Aberrations: distortion of an image, can be related to astigmatism

Accommodation: the ability of the eye to focus from distant to near objects

Acuity: sharpness of vision

Acute: occurring suddenly

Amblyopia: also known as a “lazy eye”, decreased vision without any apparent disease or organic cause, not correctable with glasses or surgery

Amsler grid: chart with black horizontal and vertical lines used for detecting problems with central vision (macular area)

Angle: area formed between the cornea and iris where fluid drains out of the eye

Antioxidants: nutrients taken in vitamin form to neutralize free radicals (molecules implicated as causative agents in cancer and aging.

Antireflective coating: coating on glasses to minimize glare

Aphakia: absence or removal of natural lens of the eye

Aqueous humor: fluid providing nutrients to cornea and maintaining pressure of the eye

ARMD: age related macular degeneration, disease by which macula is damaged causing loss of central vision.

Asthenopia: eyestrain

Astigmatism: this is a type of refractive error where the shape of the eye causes light rays entering to focus in two meridians, therefore requiring a sphero-cylindrical spectacle or toric contact lens to correct.

Bifocals: spectacles with two focal lengths, the top for distance and the bottom for reading

Binocular vision: simultaneous use of the two eyes, normal binocular vision allows for depth perception

Blepharitis: inflammation of the eyelids

Capsular haze: a thin film or haze that occasionally develops on the back surface of the capsule containing the lens implant after cataract surgery, also known as a second or after cataract, the film is removed with a yag laser.

Cataract: a clouding of the normal clear lens of the eye causing decreased vision and correctable with cataract surgery

Clear Lens Extraction: procedure in which the eye’s natural clear crystalline lens is removed and replaced with an intraocular lens implant, using the same technique as cataract surgery.

Conjunctivitis: inflammation or infection of the mucous membrane covering the sclera (white part of eye). Symptoms include redness, discharge, and irritation.

Cornea: transparent tissue covering the front part of the eyeball and provides the majority of the focusing power for the eye.
Corneal transplant (penetrating keratoplasty): surgical procedure to graft a donor cornea onto an eye.

Diabetes mellitus: chronic metabolic disorder characterized by a lack of insulin secretion and/or increased cellular resistance to insulin, resulting in elevated blood levels of simple sugars. Can cause damage to the kidneys, eyes, vascular and nervous system.

Diabetic retinopathy: deterioration of retinal blood vessels in diabetic patients, possibly leading to vision loss.

Diplopia: double vision

Dry eye: decreased tear production resulting in ocular discomfort (burning, sandy gritty feeling, intermittent blurring of vision and increased tearing).

Esotropia: over-convergence of eye position; the fixating eye is straight the other turns inward

Exotropia: position of the eyes in an over-diverged position so that the non-fixating eye is turned outward

Extraocular muscles: six muscles that control eye movement

Flashes: light spots or streaks signifying traction on the retina

Floaters: dark moving specks due to the liquefied vitreous or blood

Fluorescein angiography: diagnostic test to look for abnormal blood vessels or bleeding within the retina of the eye. The test is performed by injecting dye into the vein of an arm and photographing its movement within the eye.

Ghost image: faint or very blurred second image adjacent to the image being viewed.

Giant papillary conjunctivitis: allergic response of the eyelids to contact lens overwear or seasonal allergies. Bumps form on the inside of the eyelids and can cause itching and discharge.

Glaucoma (Acute Angle Closure): decreased visual field and optic nerve damage due to sudden angle closure with resulting extreme elevation of eye pressure. Anatomically smaller eyes and higher amounts of hyperopia (far-sightedness) are more at risk. Symptoms include pain, redness, blurred vision, and/or halos around lights. If untreated severe damage can occur within hours.

Glaucoma (Primary Open Angle): painless disease of the eye caused by elevated eye pressure resulting in gradual damage to the optic nerve and decreased peripheral vision. If untreated can lead to blindness.

Inflammation: the body’s reaction to infection, trauma, foreign substance, often associated with redness, pain, heat, and swelling.

Intraocular pressure (IOP): pressure within the eye created by the continual production and drainage of fluid.

Iridotomy: laser treatment for angle closure glaucoma to reduce the eye pressure and open the angle. Also performed prophylactically to prevent an angle closure attack.

Iris: muscular tissue (colored part of the eye) that is responsible for regulating the amount of light coming into the eye by controlling the pupil (black spot in center of color).

Ischemia: blockage or restriction of blood flow, can result in temporary or permanent impairment.

Keratitis: irritation of cornea

Keratoconus: degenerative corneal disease resulting in thinning and formation of a “cone shape”. Can be treated with rigid contact lenses and corneal transplant if scarring reduces vision.

Laser: highly concentrated beam of light used to re-shape tissue or reduce bleeding/fluid leakage within the eye.

LASIK: Laser Assisted In-Situ Keratomileusis, a refractive surgery which uses a laser to correct vision

Lazy eye: decreased vision not correctable by glasses or contacts occurring from an uncorrected eye turn or prescription during childhood, also known as amblyopia

Limbal relaxing incisions: small incisions placed on the far peripheral aspect of the cornea, often during cataract surgery to create a rounder cornea and reduce astigmatism.

Lutein: vitamin, similar to beta-carotene, thought to help slow the progression of diseases like macular degeneration.

Macula: area of retina with highest density of photoreceptors, responsible for fine acuity (vision) and color perception

Macular edema: collection of fluid in and under the macular portion of the retina.

Macular Degeneration: retinal disease of the macula causing loss of central vision.

Monovision: vision correction that utilizes one eye for distance vision and the other eye for near vision. Can be achieved by contact lenses, refractive surgery or cataract surgery.

Myopia: also known as nearsightedness, without correction distant objects are blurry while near objects are clearer.

Neovascularization: describes new blood vessel growth, are often fragile and leak easily, and often seen with diseases like diabetes and wet macular degeneration.

Ocular hypertension: elevated intraocular pressure of the eye without any signs of glaucoma. Pressure is treated or just monitored depending on amount of elevation.

OD: abbreviation meaning right eye

Ophthalmologist: as defined by the American Academy of Ophthalmology “ an eye MD is an ophthalmologist, a medical doctor who specializes in eye and vision care. Eye MD's are specially trained to provide the full spectrum of eye care, from prescribing glasses and contact lenses to complex and delicate eye surgery. Many Eye MD's are also involved in scientific research into the causes and cures for eye diseases and vision problems.”

Ophthalmoscopy: examination of the interior structures of the eye using specially designed eye instruments.

Optician: Expert who designs, verifies and dispenses lenses, frames and other fabricated optical devices upon the prescription of an optometrist or ophthalmologist.

Optometrist: as defined by the American Optometric Association “ a doctor of optometry is an independent primary health care provider who examines, diagnoses, treats, and manages diseases and disorders of the visual system, the eye and associated structures as well as diagnosing related systemic conditions. Optometrists examine the internal and external structure of the eyes to diagnose eye diseases like glaucoma, cataracts, and retinal disorders; systemic diseases like hypertension and diabetes. They prescribe eyeglasses, contact lenses, low vision aids, vision therapy, and medicines to treat eye diseases.”

OS: abbreviation meaning left eye.

Pachymetry: exam for measuring corneal thickness

Phakic Intraocular Lenses: lenses placed in front of the natural lens to correct vision, similar to an internal contact lens.

Photocoagulation: using heat therapy to cauterize or seal retinal tears or blood vessels within the eye.

Photophobia: sensitivity to light

Pinguecula: benign fibrovascular growth on the conjunctiva caused by sun and wind damage, appears yellowish and thickened. form ofconjunctivitis

Posterior Vitreous Detachment: age-related condition whereby the vitreous separates from the retinal surface, often accompanied by floaters and sometimes flashes.

Presbyopia: reduced elasticity of the natural lens causes a decreased ability to focus on near objects, usually begins at age 40 and is correctable with reading glasses

Progressive lenses: no line bifocal lenses

Retina: tissue lining the inner wall of the eye composed of light sensitive rods and cones; these cells capture light and transform that energy into chemical signals that can be interpreted by the brain into images.
Retinal Detachment: retina tears away from the tissue below and if not treated promptly will result in permanent vision loss.

Sclera: white part of the eye

Strabismus: eye muscles do not work properly to keep the eyes aligned, seen as one eye turning in or out, associated with amblyopia or lazy eye. Can be treated surgically or with vision therapy.

Tonometry: method for measuring intraocular pressure.

Toric: eyeglass or contact lens that is specially designed to correct astigmatism.

Trabeculoplasty: laser treatment for glaucoma in which the drainage area of the eye (trabecular meshwork) is remodeled using a laser to improve outflow.

Vision Therapy: eye exercises to improve vision, comfort, and the ability of the two eyes to work together.

Vitreous: jelly-like substance between the lens and retina of the eye; area that “floaters” develop in.

YAG laser surgery: also known as yag laser capsulotomy, used to remove haze that can develop over intraocular lens implants after cataract surgery.