Glossary of Terms

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Below is a list of terms used in our industry. If you don't find a term, please feel free to email us.

Amblyopia - Commonly known as "lazy eye" - is the loss or lack of central vision in one eye or the inability of the eye to focus.

Astigmatism - An additional curvature on the surface of the cornea, or lens of the eye, that makes it difficult to focus. Slight degrees can cause headaches, fatigue, and poor schoolwork. More serious degrees produce blurred vision at all distances.

Cataracts - Usually develop gradually and without pain as the lens in the eye loses transparency as the crystalline lens becomes cloudy and the lens material yellows. The result is gradual loss of brightness and a slight skewing of color perception that usually goes unnoticed. Cataracts are the leading cause of visual disability in people older than 65.

Conjunctiva - The delicate membrane that lines the eyelids and covers the exposed surface of
the eyeball.

Conjunctivitis - An inflammation of the conjuctiva, the thin, transparent layer that lines the inner eyelid and covers the white part of the eye. – American Optometric Association

Diabetic Retinopathy - Can weaken and cause changes in the small blood vessels that nourish your eye's retina, the delicate, light-sensitive lining of the back of the eye. These blood vessels might begin to leak, swell, or develop brush-like branches. Early stages can cause blurred vision, or they might produce no visual symptoms at all. As the disease progresses, you might notice a cloudiness of vision, blind spots, or floaters. – American Optometric Association

Diplopia - Double vision.

Dry Eye Syndrome - Is a chronic reduction of tears produced by the tear glands, resulting in itching or burning eyes and reduced visual acuity.  You can get several brands of artificial tears over-the-counter however your Optometrist may wish to prescribe a more proactive treatment such
as Restasis.

Farsightedness or Hyperopia - A vision condition in which distant objects are usually seen clearly, but close ones do not come into proper focus. Occurs if your eyeball is too short or the cornea has too little curvature, so light entering your eye is not focused correctly.
– American Optometric Association

Floaters - Tiny spots or specks that float across the field of vision. While floaters are usually harmless, they can be a warning of certain eye problems, especially if there is a sudden change.

Glaucoma - A condition of the eye characterized by increased intraocular pressure.  Usually controlled by medication, however when it is left untreated can result in loss of vision.

Macular Degeneration - The degeneration of the nerve endings in the macula area and is found more commonly in aults over 60.  Macular Degeneration is listed as the leading cause of blindness in America by the American Optometric Association.

Nearsightedness or Myopia - A vision condition in which near objects are seen clearly, but distant objects do not come into proper focus. Occurs if your eyeball is too long or the cornea has too much curvature, so the light entering your eye is not focused correctly. It is a very common vision condition that affects nearly 30 percent of the U.S. population. – American Optometric Association

Ocular Hypertension - An increase in the pressure in your eyes that is above the range considered normal with no detectable changes in vision or damage to the structure of your eyes. The term is used to distinguish people with elevated pressure from those with glaucoma. It can occur in people of all ages, but it occurs more frequently in African-Americans, and people older than 40 with family histories of ocular hypertension and/or glaucoma. It is also more common in people who are very nearsighted or who have diabetes. – American Optometric Association

Presbyopia - Is a gradual decline in the ability to focus on close objects or small print which usually presents itself after the age of 40.  It is described by the American Optometric Association as a vision condition in which the crystalline lens of your eye loses its flexibility, which makes it difficult to focus on close objects.

Retinal Detachment - When the neural layers of the retina separate from their blood supply due to trauma or can be idiopathic. A retinal detachment can cause loss of vision.

Sclera - The tough, white, protective coat of the eye.

Strabismus - Is the failure of the two eyes to direct their gaze at the same object simultaneously due to muscular imbalance.

Automated Visual Fields - Determine peripheral and central vision disorders, which can be caused by a variety of conditions including glaucoma.

Autorefractor - Determines a general prescription for nearsightedness, farsightedness,
and astigmatism.

Biomicroscope/Slit Lamp - Examines the external eye for abnormalities including scaring
or foreign objects.

Intraocular Pressure - Is the pressure of the fluid inside the eye; normal IOP varies
among individuals.

Keratometer - An instrument used to measures curve of a patient’s cornea; used in fitting
contact lenses.

Lensometer - An instrument which measures the power of eyeglass lenes.

Ophthalmoscope - A noninvasive, handheld instrument used to examine the internal portion
of the eye for a wide range of problems.

Phoropter - A mask-like instrument positioned so that each eye sees through a separate lens to determine the refractive state of each eye.

Tonometer - An instrument for measuring the interior pressure of the eye by varying means to determine the presence of glaucoma.

Dilation - Dilation is a process by which the pupil is temporarily enlarged with special eye drops, allowing the eye care specialist to better view the inside of the eye to detect physiological defects that may impair a patient’s vision.

- A test to determine the degree of nearsightedness, farsightedness, or astigmatism using a series of lenses which are adjusted before your eyes to determine the best correction.

Optician - As defined by the Opticians Association of America, opticians are professionals in the field of designing, finishing, fitting, and dispensing of eyeglasses and contact lenses, based on an eye doctor's prescription. The optician also might dispense colored and specialty lenses for particular needs, as well as low-vision aids and artificial eyes.

- As defined by the American Academy of Ophthalmology, an ophthalmologist is a physician (doctor of medicine or doctor of osteopathy) who specializes in the comprehensive care of the eyes and visual system in the prevention of eye disease and injury. The ophthalmologist is a physician who is qualified by lengthy medical education, training, and experience to diagnose, treat, and manage all eye and visual system problems, and is licensed by a state regulatory board to practice medicine and surgery.

Optometric Assistant - An optometric assistant is primarily involved in front-office procedures, optical dispensing, and contact lens patient education. A registered optometric assistant is designated by Opt. A., R. – American Optometric Association

Optometric Technician
- The paraoptometric technician is prepared for widely diversified job duties through academic and clinical experience. Technicians work directly with optometrists in the areas of patient examination and treatment, including contact lenses, low vision, vision therapy, optical dispensing, and office management. A registered optometric technician is designated by Opt. T., R. – American Optometric Association

- Doctors of optometry are independent healthcare providers who examine, diagnose, treat, and manage diseases and disorders of the visual system, the eye, and associated structures, as well as diagnose related systemic conditions. Optometrists are state-licensed healthcare professionals. They prescribe glasses, contact lenses, low vision rehabilitation, vision therapy, and medications, as well as perform certain surgical procedures. They hold a doctor of optometry (O.D.) degree. – American Optometric Association.

Anti Reflective (A-R) Coating - Anti-Reflective Coating blocks glare while allowing more light through to your eye than conventional lenses.  This results in sharper vision at night and reduction of eyestrain during computer usage.

Bifocal Lenses - Bifocal lenses provide clear distance vision through upper portion of the lens and clarity of objects that are closer through the lower portion.  The lower portion of the lens is restricted to eighteen to twenty-four inches away.

Mirror Coating - Mirror coating is an enhancement coating for sunglasses.  Like a mirror, it reflects; thus casting harsh light away from the eyes, providing comfort when bright light is being reflected of surfaces such as water or snow.

Multifocal Lenses - Multifocal Lenses are designed with two or more prescriptions to allow a Presbyopic patient clear vision at varying distances.

Polarized - Polarized lenses cut down on the reflected glare from water, a snow or reflective surfaces.  With polarized sunglasses the surface of the water seems more transparent, that is why they are so popular with fishermen.  And because polarized sunglasses block glare coming off a flat surface, they are also popular with truck drivers and for general outdoor activities.
Single Vision Lenses - Single vision lenses provide correction with only one focal point or range of distance. They correct hyperopia or myopia, including the condition of astigmatism.

Tints - Tints can be applied to most lenses by either absorption or surface coating. Tints come in a variety of colors and shades and can be used for minor glare reduction or sunglasses.

Trifocal Lenses - Trifocal lenses provide correction for three varying fields of vision, including distance, intermediate and near.

Ultraviolet (UV) Coating
- Ultraviolet coating reduces the absorption of harmful UVA and UVB rays that can damage the cornea.

Glass Lenses - Glass lenses can provide good scratch resistance, however glass is heavy, can be uncomfortable to wear and prone to breakage or cracking.

High Index - Hi Index is a plastic lens material that is thinner and lighter for patients with
higher prescriptions.

Plastic Lenses - Plastic lenses are lighter in weight than glass, but not as scratch resistant. Scratch-resistant coating can be applied to plastic lenses and is highly recommended.
Polycarbonate Lenses - Polycarbonate is the strongest and safest lens material available.
The material was originally designed for aviation windshields. They are the most impact-resistant lenses available today, and are commonly used for children's glasses, sports glasses, and
safety glasses.

Scratch Resistant - Is a coating that increases the durability of the surface of eyeglass lenses. It can be applied to the front and back of plastic, polycarbonate, and hi-index lenses.