Aniseikonia

Aniseikonia is a condition in which there is a relative difference in size and/or shape of the ocular images. An iseikonic lens is used to correct aniseikonia. Aniseikonia often results from antimetropia or severe anisometropia.

Anisometropia

A condition in which the type of refractive error is the same for both eyes but the amount of the error is considerably unequal, usually greater than 2.00 diopters of difference. This condition may be corrected with glasses and/or contact lenses.

Antimetropia

In this condition, one eye is myopic and one eye is hyperopic. This condition may be corrected with glasses and/or contact lenses.

Aphakia

Aphakia is the absence of the crystalline lens of the eye, due most frequently to the removal of a cataract.

Arcus Senilus

Grayish white ring in the periphery of the cornea.

Blepharitis

Inflammation of the margins of the eyelids.

Bullous Keratopathy

Total swelling of the cornea with painful blister formation at the epithelial level; treated frequently with a therapeutic soft lens.

Cataracts

A cataract is any opacity of the crystalline lens. To be clinically significant, it must cause a significant reduction in acuity or a functional impairment. Cataracts can result from aging, an accident, hereditary factors, medications, and nutritional disorders. Treatment involves surgical removal of the lens. When patients have no crystalline lens they are referred to as aphakic.

Chalazion

Inflammatory enlargement of a Meibomian gland of the eyelid.

Chemosis

Severe edema of the conjunctiva.

Circumcorneal Injection

Redness around the limbus surrounding the cornea.

Tight lenses, sensitivities to solutions and keratitis may all result in circumcorneal injection in soft lens
wearers.

Conjunctivitis

Conjunctivitis is a nonspecific term used to describe an inflammation of the conjunctiva caused by a wide range of conditions. It is commonly referred to as “pink eye”. It is classified clinically according to the underlying cause. The most common causes are bacterial, viral, allergic, and contact lens related. It is possibly contagious and rooms should be disinfected after anyone with a red eye uses any equipment.

Corneal Edema

Swelling of the cornea caused by hypoxia or insufficient oxygen.

Dellen

A depressed area on the cornea which shows stain due to lack of wetting from the pre-corneal tear film. It is generally found adjacent to an elevated area.

Diplopia

Diplopia occurs when a single object is perceived as two objects instead of one (Double Vision). This condition may be aided with the use of prism. A sudden onset of diplopia in adults is unusual and requires in-depth examination by the doctor.

Dry Spots

Areas of drying as noted by absent areas of fluorescein-stained tear film on the cornea when the patient stares.

Ectropion

An eversion or turning outward of the eyelid.

Endophthalmitis

An inflammation of the entire eye including the outer coats.

Entropion

Turning inward of the eyelid.

Epithelial Edema

Edema of the superficial layer of the cornea.

Eversion of the Eyelid

The folding back of the eyelid on itself.

Fuch’s Dystrophy

Edema in the stroma associated with scarring on both the endothelium and epithelium.

Ghost Vessels

Empty vessels remaining after corneal invasion by blood vessels.

Giant Papillary Conjunctivitis (GPC)

Large elevated papules in the tarsal conjunctiva. Usually associated with soft lens wear.

Glaucoma

In glaucoma, the intraocular pressure becomes elevated because the eye produces too much fluid and/or the fluid cannot drain from the eye properly. Because of the high pressure, the optic nerve becomes damaged resulting in gradual vision loss. This is usually a silent disease, thus necessitating routine screenings. There is no cure, but treatment involves medications and/or surgery.

Hypoxia

Low in oxygen.

Keratitis Sicca

Dryness of the cornea.

Keratitis

Inflammation of the cornea.

Keratoconjunctivitis Sicca

Drying of the cornea and conjunctiva.

Keratoconus

A degeneration of the cornea causing irregular and severe astigmatism in which the cornea becomes curved or conical in shape.. Patients require specialty contact lens fitting, usually with rigid gas permeable lenses.

Nebula

A faint or slightly misty corneal opacity.

Neovascularization

Abnormal growth of new blood vessels in the cornea.

Nystagmus

Nystagmus is an involuntary, rapid movement or rotation of the eye. Nystagmus is often associated with photophobia. Patients with a significant refractive error may profit from contact lenses because the lenses move with the eye.

Overwearing Syndrome

A misnomer for acute corneal hypoxia characterized by a latent interval after removal of the lens; extreme pain and congestion of lids, cornea, and conjunctiva are experienced. It is more common with rigid lenses.

Pannus

Invasion of the peripheral cornea by infiltration and formation of the new blood vessels.

Phoria

Phoria is a condition in which an ocular muscle is out of balance. This muscle imbalance creates a tendency in which the eye turns away from its normal position when fusion is broken. The brain has a natural tendency to create fusion. However, when fusion is broken by something obstructing a person’s line of sight, the eye will have a tendency to turn away from its normal position. Once the line of sight is clear, fusion will generally occur.

Photophobia

Photophobia is an abnormal sensitivity or intolerance of light.

Pinguecula

Yellowish, triangular thickening of bulbar conjunctiva, nasal or temporal to the cornea.

Pterygium

A triangle fold of growing membrane that may extend over the cornea from the white of the eye. It occurs most frequently in persons exposed to dust, sun, or wind.

Ptosis

Ptosis is a drooping of the upper eyelid. A ptosis crutch may be used to elevate the drooping upper eyelid. Surgery is also available to help correct this condition.

Spectacle Blur

Blurred vision that lasts for 30 minutes or longer after a rigid lens is removed and spectacles are employed.

Strabismus

Strabismus, know as “crossed eyes”, is a muscle or refractive imbalance that prevents normal binocular vision. This condition may be aided with the use of prism, vision therapy, or surgery to help with either visual acuity or the cosmetic appearance of the eye.

Strippling

Dotlike staining of the cornea.

Superficial Punctate Keratitis (PSK)

Diffuse stippling of the cornea.

Three and Nine O’Clock Staining

Erosion of the cornea at the 3 and 9 o’clock position; seen usually in patients wearing rigid lenses.

Tropia

Tropia is a definite turning of an eye away from its normal position. Both eyes are not focusing on the object viewed. The brain cannot overcome the turning of the eye to create fusion. Tropia may result from a weak or damaged ocular muscle or from the brain’s inability to create fusion.

Ulceration of the Cornea

A large defect in the cornea which may be caused by hypoxia, trauma, or infection.

Vascularization

Increased blood vessels occurring in a cornea.