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The word “presbyopia” comes from the Greek and means “elder eye.” Presbyopia is the vision condition where as we age, the crystalline lens of the eye loses its flexibility making it difficult to focus up close. After age 40, people begin to experience blurred vision at near points such as when reading or working on a computer. This happens to everyone when they age, even those individuals who have never had a prior vision problem.
Changes to the proteins in the lens of the eye cause the lens to harden gradually reducing flexibility. Age-related changes also take place in the muscle fibers surrounding the lens.
Common signs of presbyopia include a tendency to hold reading materials at arms length, eye fatigue, and headaches.
Presbyopia is detected during a comprehensive eye exam through a test called refraction. By using a phoropter, an instrument that determines the type and measures the amount of presbyopia present, your eye doctor will determine your exact prescription. Because the human lens will continue to change, as you get older your presbyopic prescription will increase over time.
There are many options for the treatment of presbyopia; reading glasses, eye glasses with progressive addition lenses, bifocals, trifocals, and contact lenses are the most common. Studies are currently underway for the surgical treatment of presbyopia as well.
Myopia, or nearsightedness, is a common vision condition, or refractive error, that affects nearly 30% of the population in the United States. A refractive error means that the shape of your eye doesn't refract the light properly, so that the image you see is blurred. Myopia occurs when the curvature of the cornea is too steep or the eyeball is too long, causing light entering the eye to be focused in front of the retina, rather than directly on the retina. Near objects are seen clearly, but objects in the distance appear blurry. For our eyes to be able to see, light rays must be bent or “refracted” so they can focus directly on the retina, the nerve layer that lines the back of the eye. Together, the cornea and the lens refract rays. The retina receives the picture formed by these light rays and sends the image to the brain through the optic nerve.
Myopia is thought to be hereditary. Since the eye continues to grow during childhood, myopia generally continues to develop over the childhood years typically stabilizing by the age of 18.
Difficulty seeing objects in the distance while watching television, or looking at the chalkboard, frequent headaches, and eyestrain are common symptoms of myopia.
Myopia is detected during a comprehensive eye exam through a test called refraction. By using a phoropter, an instrument that determines the type and measures the amount of refractive error present, your eye doctor will determine your exact prescription.
Prescription eyeglasses, contact lenses, and LASIK surgery (laser vision correction) are treatment options to optically correct myopia.
Hyperopia, or farsightedness, is a common vision condition, or refractive effort that affects nearly 25% of the population in the United States. A refractive error means that the shape of your eye doesn't’t refract the light properly, so that the image you see is blurred. Hyperopia occurs when the curvature of the cornea is shorter than normal or the curvature of the cornea is too flat, causing light entering the eye to be focused behind the retina rather than directly on the retina. Objects in the distance are seen clearly, but objects close up appear blurry.
For our eyes to be able to see, light rays must be bent or “refracted” so they can focus directly on the retina, the nerve layer that lines the back of the eye. Together, the cornea and the lens refract light rays. The retina receives the picture formed by these light rays and sends the image to the brain through the optic nerve.
Hyperopia is thought to be hereditary and many children are born with farsightedness. Since the eye continues to grow during childhood, many “outgrow” this condition as the eyeball lengthens with normal growth.
Common signs include difficulty maintaining a clear focus on near objects, eyestrain, fatigue, headaches after close work, and difficulty concentrating.
Hyperopia is detected during a comprehensive eye exam through a test called refraction. By using a phoropter, an instrument that determines the type and measures the amount of refractive error present, your eye doctor will determine your exact prescription. In mild cases, your eye may be able to compensate without having to wear corrective lenses. It is important to note that the common vision screenings performed in schools are generally ineffective in detecting hyperopia in children.
Prescription eyeglasses, contact lenses and LASIK surgery (laser vision correction) are treatment options to optically correct hyperopia.
Astigmatism is a common vision condition, or refractive error, that often accompanies myopia (nearsightedness) and hyperopia (farsightedness). A refractive error means that the shape of your eye does not refract the light properly, so that the image you see is blurred. Astigmatism occurs when the curvature of the cornea is irregularly shaped, scattering light rays entering the eye so that they are focused in front of and behind the retina, rather than directly on the retina. Vision is blurred at all distances. For our eyes to be able to see, light rays must be bent or “refracted” so they can focus directly on the retina, nerve layer that lines the back of the eye. Together, the cornea and the lens refract light rays. The retina receives the picture formed by these light rays and sends the image to the brain through the optic nerve.
Astigmatism results when the eye is shaped more like a football than a baseball, which is the normal shape of the eye. Many people are born with this oblong shape and the resulting vision problem may get worse over time.
Common signs of astigmatism include difficulty maintaining a clear focus on near and far objects, eyestrain, fatigue and headaches.
Astigmatism is detected during a comprehensive eye exam through a test called refraction. By using a phoropter, an instrument that determines the type and measures the amount of refractive error present, your eye doctor will determine your exact prescription.
Prescription eyeglasses, contact lenses, and LASIK surgery (laser vision correction) are treatment options to optically correct astigmatism.
Conjunctivitis is an inflammation of the thin, transparent layer that lines the inner eyelids and covers the white part of the eye. There are three types of conjunctivitis: infectious, allergic and chemical.
Infectious conjunctivitis, or “pink eye”, as it is commonly called, is caused by a virus or bacteria. Allergic conjunctivitis is a systemic effect of the body’s allergies to pollen, cosmetics, certain fabrics or animals. It is estimated that over 22 million Americans suffer from some form of allergic conjunctivitis. Irritants such as air pollution and chlorine in swimming pools can cause chemical conjunctivitis.
Common symptoms include red watery eyes, mild discomfort, inflamed inner lids, blurred vision, a scratchy feeling in the eyes and occasional discharge.
Your eye care professional will examine your eyes and ask questions to determine which type of conjunctivitis you have. In some cases, a sample may be collected and sent for analysis.
Both bacterial and viral conjunctivitis are highly contagious. Wash your hands frequently and avoid touching or rubbing your eyes. Warm compresses help soothe your eyes as well. If you find that warm compresses don't help, feel free to try cold compresses. Viral conjunctivitis typically clears up on its own after a few days. Antibiotic drops are prescribed to treat bacterial conjunctivitis. Over-the-counter antihistamine allergy pills or eye drops are recommended to control the irritation.
Amblyopia is the most common vision problem in children under the age of six, affecting two to three out of every 100 children. In order to see properly, the brain and the eye must work together. As light enters the eye, nerve signals traveling along the optic nerve send visual images to the brain. Amblyopia, or “Lazy Eye” as it is often called, is the condition where vision in one eye is reduced because the signals to the eye and the brain do not synchronize properly. The amblyopic eye has the capability to see; however, the brain favors the healthier eye. Untreated, amblyopia can lead to vision impairment in adults.
Amblyopia can be caused when one eye is more nearsighted, farsighted or has more astigmatism than the other eye. Strabismus, an imbalance in the position of the two eyes, can also cause amblyopia.
The symptoms of amblyopia include squinting, blurred vision, closing one eye to see, favoring one eye over the other and a tendency to bump into things. Frequent headaches due to eyestrain are also a sign.
During the first nine months of life, the visual system develops very rapidly. Your eye care professional can determine if amblyopia is present during an eye examination. Treatment of amblyopia is most effective before the age of seven, making early diagnosis important.
Treatment options include prescription eyewear, Atropine drops to temporarily blur the stronger eye stimulating vision in the weaker eye, and patching the eye.
Uveitis is an inflammation in the middle layer of the eye affecting three structures: the iris (the colored part of the eye), the ciliary body (surrounding muscle tissue) and the choroid (blood vessels). Uveitis can affect all or just one of these structures. Left untreated, it can cause permanent damage and loss of vision from the development of glaucoma, cataracts or retinal edema.
Uveitis often develops as a complication of other eye diseases or in association with other health problems such as rheumatoid arthritis, rubella or mumps. Eye trauma can also cause the condition, and in many cases there is no underlying cause.
Symptoms of uveitis include a red, sore inflamed eye, blurred vision, excessive blinking, sensitivity to light and pain. The normally clear cornea may appear dull or a hazy blue. Symptoms can appear suddenly, and there may be no pain.
Uveitis is diagnosed by examining the eye with instruments that magnify and illuminate the structure of the eye during a dilated eye exam. Once uveitis is diagnosed, a general health exam is often recommended to determine the cause.
Medication is most often used to treat uveitis. Corticosteroids in the form of injections, drops or oral medication may be prescribed to reduce inflammation as well as eye drops to dilate the pupil and reduce pain.
Keratoconus is a progressive condition, often appearing in the late teens or early twenties, where the cornea thins and changes to form a cone-like shape. This change prevents light entering the eye to be properly focused on the retina causing distorted vision. The condition may progress for ten to 20 years eventually slowing its progression. One eye or both eyes may be affected.
For our eyes to be able to see, light rays must be bent or “refracted” so they can focus directly on the retina, the nerve layer that lines the back of the eye. Together the cornea and the lens refract light rays. The retina receives the picture formed by these light rays and sends the image to the brain through the optic nerve.
What causes keratoconus is unclear. Doctors speculate that a genetic link may exist as several members in extended families often have the condition.
Keratoconus is often difficult to detect as the changes in the cornea progress slowly and is often accompanied by myopia or hyperopia. This combination causes both distorted and blurred vision. Frequent prescription changes and sensitivity to light and glare are also common symptoms.
One of the best methods for detecting keratoconus is with a machine called a corneal topographer. This painless test maps the shape of the eye and produces a colored map of changes in the cornea.
In mild forms of keratoconus, glasses and contact lenses are prescribed. As the condition progresses, rigid gas permeable contact lenses are the recommended treatment methods.
If keratoconus reaches the point where an individual can no longer tolerate a lens, or contacts no longer provide adequate vision, surgical treatment may be recommended in the form of a corneal transplant or penetrating keratoplasty. Studies are also underway on corneal implants to improve vision.
Blepharitis is simply an inflammation of the outer edges of the eyelids where the eyelashes originate. It is a common condition that may never totally go away, but it can be controlled by treatment.
Crusts form on the eyelid margins and are continually flaking off. It can be irritating especially if the crust falls into your eyes, causing a foreign body sensation. The eyes may itch or look bloodshot and the edges of your eyelids may stay red much of the time, making it look as if you have been crying.
Blepharitis can be caused by a number of infectious organisms, though in most cases it is related to seborrhea, a common condition of the skin and hair know as dandruff. Rubbing your eyes could add to the likelihood of lid infections. Blepharitis does not affect your eyesight.
1. Wash your hands with soap and water.
2. While looking in the mirror, moisten a cotton swab (Q-Tip) with warm tap water (adding a few drops of baby shampoo if prescribed) and gently “tease” and clean all the crusts from the edge of your eyelids and the eyelashes. Do not pull the crusts off with your fingers, as this increases the risk of infection.
3. When all the crusts are cleaned off:
a. Put 2 drops of your prescribed medication into each eye. Do not wipe away the excess that runs out, but use another swab to rub it into the edge of the lid and eyelashes. Don’t wash it off.
b. If an ointment medication was prescribed, rub a thin layer into the eyelid margin with a cotton swab at night before going to bed.
Repeat this procedure 2 or 3 times a day for 7 to 10 days.
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PRESBYOPIA 
HYPEROPIA
