Amblyopia-Lazy eye, or amblyopia, is the loss or lack of development of central vision in one eye that is unrelated to any eye health problem and is not correctable with lenses. It can result from a failure to use both eyes together. Lazy eye is often associated with crossed-eyes or a large difference in the degree of nearsightedness or farsightedness between the two eyes. It usually develops before the age of 6, and it does not affect side vision.
Symptoms may include noticeably favoring one eye or a tendency to bump into objects on one side. Symptoms are not always obvious.
Treatment for lazy eye may include a combination of prescription lenses, prisms, vision therapy and eye patching. Vision therapy teaches the two eyes how to work together, which helps prevent lazy eye from reoccurring.
Early diagnosis increases the chance for a complete recovery. This is one reason why the American Optometric Association recommends that children have a comprehensive optometric examination by the age of 6 months and again at age 3. Lazy eye will not go away on its own. If not diagnosed until the pre-teen, teen or adult years, treatment takes longer and is often less effective.
Astigmatism-Astigmatism is a vision condition that occurs when the front surface of your eye, the cornea, is slightly irregular in shape. This irregular shape prevents light from focusing properly on the back of your eye, the retina. As a result, your vision may be blurred at all distances.
People with severe astigmatism will usually have blurred or distorted vision, while those with mild astigmatism may experience headaches, eye strain, fatigue or blurred vision at certain distances.
Most people have some degree of astigmatism. A comprehensive optometric examination will include testing to diagnose astigmatism and determine the degree.
Almost all levels of astigmatism can be optically corrected with properly prescribed and fitted eyeglasses and/or contact lenses.
Blepharitis-Blepharitis is a chronic or long-term inflammation of the eyelids and eyelashes. It affects people of all ages. Among the most common causes of blepharitis are poor eyelid hygiene; excessive oil produced by the glands in the eyelid; a bacterial infection (often staphylococcal); or an allergic reaction.
In many cases, good eyelid hygiene and a regular cleaning routine may control blepharitis. This includes frequent scalp and face washing; warm soaks of the eyelids; and eyelid scrubs. In cases where bacterial infection is a cause, eyelid hygiene may be combined with various antibiotics and other medications. Eyelid hygiene is especially important upon awakening because debris can build up during sleep.
If you experience symptoms of blepharitis, your doctor of optometry can determine the cause and recommend the right combination of treatments specifically for you.
Conjunctivitis-Conjunctivitis is an inflammation of the conjunctiva, the thin, transparent layer that lines the inner eyelid and covers the white part of the eye.
The three main types of conjunctivitis are infectious, allergic and chemical. The infectious type, commonly called "pink eye," is caused by a contagious virus or bacteria. Your body's allergies to pollen, cosmetics, animals or fabrics often bring on allergic conjunctivitis. And, irritants like air pollution, noxious fumes and chlorine in swimming pools may produce the chemical form.
Common symptoms of conjunctivitis are red watery eyes, inflamed inner eyelids, blurred vision, a scratchy feeling in the eyes and, sometimes, a puslike or watery discharge. Conjunctivitis can sometimes develop into something that can harm vision so you should see your optometrist promptly for diagnosis and treatment.
A good way to treat allergic or chemical conjunctivitis is to avoid the cause. If that does not work, prescription or over-the-counter eye drops may relieve discomfort. Infectious conjunctivitis, caused by bacteria, can be treated with antibiotic eye drops. Other forms, caused by viruses, cannot be treated with antibiotics. They must be fought off by your body's immune system.
To control the spread of infectious conjunctivitis, you should keep your hands away from your eyes, thoroughly wash your hands before applying eye medications and do not share towels, washcloths, cosmetics or eye drops with others.
Cataract- A cataract is a clouding of the lens in the eye that affects vision. Most cataracts are found in persons over age 55, but they are also occasionally found in younger people. By age 80, more than half of all Americans either have a cataract or have had cataract surgery.
The lens of the eye is made mostly of water and protein. Clouding of the lens occurs due to changes in the proteins and lens fibers. Age-related cataracts tend to form gradually.
Cause of the cataract:
Most cataracts are age related. However, here are a few other causes of cataract:
Secondary cataract. Cataracts can form after surgery for other eye problems, such as glaucoma. Cataracts also can develop in people who have other health problems, such as diabetes. Cataracts are sometimes linked to steroid use.
Traumatic cataract. Cataracts can develop after an eye injury, sometimes years later.
Congenital cataract. Some babies are born with cataracts or develop them in childhood, often in both eyes. These cataracts may be so small that they do not affect vision. If they do, the lenses may need to be removed.
Radiation cataract. Cataracts can develop after exposure to some types of radiation.
When vision is clear, the lens of the eye focuses light on the back of the eye, or the retina, which transmits the image through the optic nerve to the brain. When the lens is clouded by a cataract, light scatters so the lens can no longer focus it properly, causing vision problems.
Especially in age-related cataracts, vision disruption can be very gradual. As cataracts worsen, visual symptoms tend to increase in severity. However, some patients may not recognize the change in symptoms because of a cataract's slow progression.
Cataracts-especially nuclear cataracts-can also affect one's ability to accurately differentiate color. As proteins in the eye age, they can develop a yellow or brown tint, causing vision to appear slightly tungsten. While this tinting may not affect the sharpness of one's vision, it can lead to trouble with reading or determining the difference between darker colors.
Cataracts form without pain or discomfort. However, there are several key factors which might signal the formation of a cataract:
blurred or hazy vision
the appearance of spots in front of the eyes
colors in vision seem faded or muted, or you may have difficulty distinguishing between dark colors like navy and black
increased sensitivity to glare or the feeling of having a film over the eyes
Double vision or multiple images (this might clear as the cataract grows larger)
Age in the primary risk factor for developing cataracts. However, there are other factors that can affect cataract development:
Diabetes mellitus. Persons with diabetes mellitus are at higher risk for cataracts, and persons with diabetes who have cataracts have a higher morbidity than those without cataracts.
Drugs. Certain medications have been found to be associated with the development of a cataract and vision loss. These drugs include:
· corticosteroids
· phenothiazine or other thiazines
· chlorpromazine
· Antihypertensive agents
Ultraviolet radiation. Studies have shown that there is an increased chance of cataract formation with unprotected exposure to ultraviolet (UV) radiation.
Smoking. An association between smoking and increased nuclear opacities has been reported.
Alcohol. Several studies have shown increased cataract formation in patients with higher alcohol consumption compared with patients who have lower or no alcohol consumption.
Nutrition. Although the results are inconclusive, studies have suggested an association between cataract formation and low levels of antioxidants (e.g., vitamin C, vitamin E, carotenoids). Further study may show that antioxidants have a significant effect on decreasing the incidence of cataract.
Surgical treatment
However, patients with greater visual disruption or related ocular diseases or conditions may require further treatment, including cataract surgery. Candidates for cataract surgery are typically those whose cataracts have decreased visual acuity to a point where there is a disruption to everyday tasks like driving.
The standard for cataract surgery today is the replacement of the clouded lens with a plastic intraocular lens (IOL). The artificial lens requires no care, and should dramatically improve vision for the patient. New IOL options include those that simulate the natural focusing ability of a young healthy lens.
It is important to discuss the benefits and risks of cataract surgery with your eye care providers. Other ocular conditions may increase the need for cataract surgery or prevent one from being a cataract surgery candidate. In some cases, alternatives to surgery may be available.
Cataract surgery is one of the safest and most effective types of surgery performed in the United States today. Approximately 90 percent of cataract surgery patients report better vision following the surgery.
The healing process for most cataract surgery patients is completed in 8 weeks.
Diabetic Retinopathy- Diabetes is a disease that interferes with the body's ability to use and store sugar and can cause many health problems. One, called 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 may begin to leak, swell or develop brush-like branches.
The early stages of diabetic retinopathy may cause blurred vision, or they may produce no visual symptoms at all. As the disease progresses, you may notice a cloudiness of vision, blind spots or floaters.
If left untreated, diabetic retinopathy can cause blindness, which is one reason why it is important to have your eyes examined regularly by your doctor of optometry. This is especially true if you are a diabetic or if you have a family history of diabetes.
To detect diabetic retinopathy, your optometrist can look inside your eyes with an instrument called an ophthalmoscope that lights and magnifies the blood vessels in your eyes. If you have diabetic retinopathy, laser and other surgical treatments can be used to reduce its progression and decrease the risk of vision loss. Early treatment is important because once damage has occurred, the effects are usually permanent.
If you are a diabetic, you can help prevent diabetic retinopathy by taking your prescribed medication as instructed, sticking to your diet, exercising regularly, controlling high blood pressure and avoiding alcohol and smoking.
Glaucoma-Glaucoma is an eye disease in which the internal pressure in your eyes increases enough to damage the nerve fibers in your optic nerve and cause vision loss. The increase in pressure happens when the passages that normally allow fluid in your eyes to drain become clogged or blocked. The reasons that the passages become blocked are not known.
Glaucoma is one of the leading causes of blindness in the U.S. It most often occurs in people over age 40. People with a family history of glaucoma, African Americans, and those who are very nearsighted or diabetic are at a higher risk of developing the disease.
The most common type of glaucoma develops gradually and painlessly, without symptoms. A rarer type occurs rapidly and its symptoms may include blurred vision, loss of side vision, seeing colored rings around lights and pain or redness in the eyes.
Glaucoma cannot be prevented, but if diagnosed and treated early, it can be controlled. Vision lost to glaucoma cannot be restored. That is why the American Optometric Association recommends annual eye examinations for people at risk for glaucoma (your doctor may, depending on your condition, recommend more frequent examinations). A comprehensive optometric examination will include a tonometry test to measure the pressure in your eyes; an examination of the inside of your eyes and optic nerves; and a visual field test to check for changes in central and side vision.
The treatment for glaucoma includes prescription eye drops and medicines to lower the pressure in your eyes. In some cases, laser treatment or surgery may be effective in reducing pressure.
Hyperopia- Farsightedness, or hyperopia, as it is medically termed, is a vision condition in which distant objects are usually seen clearly, but close ones do not come into proper focus. Farsightedness occurs if your eyeball is too short or the cornea has too little curvature, so light entering your eye is not focused correctly.
Common signs of farsightedness include difficulty in concentrating and maintaining a clear focus on near objects, eye strain, fatigue and/or headaches after close work, aching or burning eyes, irritability or nervousness after sustained concentration.
Common vision screenings, often done in schools, are generally ineffective in detecting farsightedness. A comprehensive optometric examination will include testing for farsightedness.
Macular Degeneration-Macular degeneration is the leading cause of blindness in America. It results from changes to the macula, a portion of the retina that is responsible for clear, sharp vision, and is located at the back of the eye.
Most people with macular degeneration have the dry form, for which there is no known treatment. The less common wet form may respond to laser procedures, if diagnosed and treated early.
Some common symptoms are a gradual loss of ability to see objects clearly, distorted vision, a gradual loss of color vision and a dark or empty area appearing in the center of vision.
If you experience any of these, contact your doctor of optometry immediately for a comprehensive examination.
Central vision that is lost to macular degeneration cannot be restored. However, low vision devices such as telescopic and microscopic lenses can be prescribed to make the most out of remaining vision.
Recent research indicates certain vitamins and minerals may help prevent or slow the progression of macular degeneration. Ask your doctor of optometry about these. After age 60, an annual, comprehensive eye examination is important to maintain eye health.
Myopia- Nearsightedness, or myopia, as it is medically termed, is a vision condition in which near objects are seen clearly, but distant objects do not come into proper focus. Nearsightedness occurs if your eyeball is too long or the cornea has too much curvature, so the light entering your eye is not focused correctly.
Nearsightedness is a very common vision condition that affects nearly 30 percent of the U.S. population. Some evidence supports the theory that nearsightedness is hereditary. There is also growing evidence that nearsightedness may be caused by the stress of too much close vision work. It normally first occurs in school-age children. Because the eye continues to grow during childhood, nearsightedness generally develops before age 20.
A sign of nearsightedness is difficulty seeing distant objects like a movie or TV screen or chalkboard. A comprehensive optometric examination will include testing for nearsightedness. Your optometrist can prescribe eyeglasses or contact lenses to optically correct nearsightedness by altering the way the light images enter your eyes. You may only need to wear them for certain activities, like watching TV or a movie or driving a car, or they may need to be worn for all activities.
Refractive surgery or laser procedures are also possible treatments for nearsightedness as is orthokeratology. Orthokeratology (ortho-k) is a non-invasive procedure that involves the wearing of a series of specially-designed rigid contact lenses to progressively reshape the curvature of the cornea over time.
Presbyopia-Presbyopia is a vision condition in which the crystalline lens of your eye loses its flexibility, which makes it difficult for you to focus on close objects.
Presbyopia may seem to occur suddenly, but the actual loss of flexibility takes place over a number of years. Presbyopia usually becomes noticeable in the early to mid-40s. Presbyopia is a natural part of the aging process of the eye. It is not a disease, and it cannot be prevented.
Some signs of presbyopia include the tendency to hold reading materials at arm's length, blurred vision at normal reading distance and eye fatigue along with headaches when doing close work. A comprehensive optometric examination will include testing for presbyopia.
To help you compensate for presbyopia, your optometrist can prescribe reading glasses, bifocals, trifocals or contact lenses. Because presbyopia can complicate other common vision conditions like nearsightedness, farsightedness and astigmatism, your optometrist will determine the specific lenses to allow you to see clearly and comfortably. You may only need to wear your glasses for close work like reading, but you may find that wearing them all the time is more convenient and beneficial for your vision needs.
Because the effects of presbyopia continue to change the ability of the crystalline lens to focus properly, periodic changes in your eyewear may be necessary to maintain clear and comfortable vision.
Strabismus- Strabismus occurs when one or both of your eyes turns in, out, up or down, and is usually caused by poor eye muscle control. This misalignment often first appears before age 21 months but may develop as late as age 6. This is one reason why the American Optometric Association recommends a comprehensive optometric examination before 6months and again at age 3.
There is a common misconception that a child will outgrow strabismus. This is not true. In fact, the condition may get worse without treatment.
Treatment for strabismus may include single vision or bifocal eyeglasses, prisms, vision therapy, and in some cases, surgery. Vision therapy helps align your eyes and solves the underlying cause of strabismus by teaching your two eyes to work together. Surgery alone may straighten your eyes, but unless your eye muscle control is improved, your eyes may not remain straight.
If detected and treated early, strabismus can often be corrected with excellent results.
Vitreal Floater-Spots (often called floaters) are small, semi-transparent or cloudy specks or particles within the vitreous, which is the clear, jelly-like fluid that fills the inside of your eyes. They appear as specks of various shapes and sizes, threadlike strands or cobwebs. Because they are within your eyes, they move as your eyes move and seem to dart away when you try to look at them directly.
Spots are often caused by small flecks of protein or other matter trapped during the formation of your eyes before birth. They can also result from deterioration of the vitreous fluid, due to aging; or from certain eye diseases or injuries.
Most spots are not harmful and rarely limit vision. But, spots can be indications of more serious problems, and you should see your optometrist for a comprehensive examination when you notice sudden changes or see increases in them.
By looking in your eyes with special instruments, your optometrist can examine the health of your eyes and determine if what you are seeing is harmless or the symptom of a more serious problem that requires treatment.
Visual Acuity- 20/20 vision is a term used to express normal visual acuity (the clarity or sharpness of vision) measured at a distance of 20 feet. If you have 20/20 vision, you can see clearly at 20 feet what should normally be seen at that distance. If you have 20/100 vision, it means that you must be as close as 20 feet to see what a person with normal vision can see at 100 feet.
In mild cases of farsightedness, your eyes may be able to compensate without corrective lenses. In other cases, your optometrist can prescribe eyeglasses or contact lenses to optically correct farsightedness by altering the way the light enters your eyes.
