Glossary of Eye Terms
Astigmatism: Irregular corneal shape (like an egg or a football) resulting in blurred vision
Amblyopia: Abnormal visual development where the brain favors one eye over the other, causing the weaker eye (the “lazy” eye) to wander. (See Lazy Eye)
Blepharitis: Infection of the eyelid
Cataract: Clouding of the normally-clear lens of the eye, results in obstructed vision
Central Serous Retinopathy: small swelling on the retina, typically self-healing, sometimes stress-related
Chalazion: Swelling of eyelid, caused by inflammation of an oil-producing gland in the upper or lower eyelid
CMV Retinitis: Serious infection of the retina, particularly risky to individuals with weak immune systems
Coats’ Disease: Chronic, progressive disorder of the retina
Conjunctivitis: “pink eye”, a contagious infection/inflammation of the clear covering of the white of the eye
Cornea: The clear “window” that covers the colored part of the eye
Corneal Abrasion: Surface-level injury to the cornea
Detached Retina: An emergency situation where the retina pulls away from the layer of blood vessels supplying oxygen and nourishment; there is risk of blindness if left untreated
Diabetic Retinopathy: Complication of diabetes; caused by damage to the blood vessels of the retina
Dry Eye: Condition caused by the erosion or diminishing of the eye’s protective tear layer
Eyelid Tumor: Abnormal growth in the eye area
Farsightedness: Ability to see distant objects clearly; near objects appear blurry (hyperopia)
Floater: Small, dark speck moving around in your field of vision; may resemble shadows or cobwebs or “floating bugs”
Flash: Similar to a floater, but resembling a twinkle or lightning streak; “seeing stars”
Glaucoma: Disease of the optic nerve; causes peripheral vision loss if left untreated
Herpes Simplex Eye Disease: Complication of HSV type 1, results in a recurrent infection of the cornea (clear window of eye, covering the colored part); can potentially threaten vision
Intravitreal Injections in the Treatment of Diabetic Retinopathy: Injections of potent medications in the eye are now commonly done in the office, and the results are usually very good. The injections are done with a local anesthetic, can be done very rapidly (usually less than a few seconds for the actual injection), and are usually associated with only a minimum amount of discomfort during and after the procedure. There are risks associated with the injections, just as there are with any surgical procedure, but these are very rare.
Ischemic Optic Neuropathy: “Stroke” of the optic nerve (the messenger which carries sight input to the brain); results in sudden loss of vision
Keratoconus: “Cone-shaped” cornea; uncommon condition where the cornea thins and protrudes
Laser In the Treatment of Diabetic Retinopathy: The main goal of laser treatment is to prevent further loss. In a sense, it “freezes” the symptoms and keeps them from getting worse. Many people experience improvement; however, in most cases, “perfect” vision will not be completely recovered after laser treatment. Multiple laser treatments over time are sometimes necessary. Laser surgery does not cure diabetic retinopathy and does not always prevent further loss of vision.
Lazy Eye: Abnormal visual development where the brain favors one eye over the other, causing the weaker eye (the “lazy” eye) to wander. See amblyopia.
Low Vision: Visual impairment that is not significantly improved by ordinary vision correction or IOL implants; distinct from blindness
Macula: small area in the center of the retina that allows us to see fine details clearly
Macular Degeneration: Distorted, blurred vision caused by the breakdown of the macula (central portion of the retina)
Macular Edema: The swelling or thickening of the macula caused by fluid leakage from the retinal blood vessels. It is the most common cause of visual loss in diabetes.
Macular Ischemia: Occurs when small blood vessels (capillaries) close. Vision blurs because the macula no longer receives sufficient blood supply to function properly.
Misaligned Eyes: Condition where one eye gazes straight ahead, and the other turns inward, outward, upward or downward
Nearsightedness: Ability to see near objects clearly, while distant objects appear blurry (also, myopia)
Ocular Histoplasmosis Syndrome (OHS): a complication of histoplasmosis (disease caused by fungus exposure); must be treated by a form of laser surgery known as photocoagulation.
Optic Nerve: bundle of nerves joining the retina to the brain
Optic Neuritis: inflammation of the optic nerve
Optical: pertaining to eyeglasses and contact lenses
Optician: someone trained to make vision correcting lenses and adjust eyewear
Presbyopia: gradual loss of lens elasticity that makes it difficult to focus on near objects; a natural result of aging
Ptosis: drooping of the upper eyelid that can block vision
Retina: thin layer of tissue at the back of the eye; transforms light into nerve signals
Retinal Vein Occlusion: a blockage in a vein in the back of the eye, causes retinal swelling and poor functioning
Retinitis Pigmentosa: disease which affects the rods and cones of the light-sensitive nerve layer at the back of the eye; night blindness and/or tunnel vision is symptomatic
Retinoschisis: genetic eye disease that splits the nerve layer at the back of the eye
Sclera: the white part of the eye
Stargardt’s Disease: an inherited disease that affects the retina; usually apparent between the ages of 8-14
Strabismus/Psuedostrabismus: misaligned eyes, or the false appearance of
Tearing: watery eyes, excessive tear production; potential causes include allergies, dry eye, infection, or another ocular condition
Toxoplasmosis: common parasitic infection that can settle in the macula and cause permanent damage
Vitreous: clear gel inside the eye that fills the space between the lens and the retina
