Common Eye Conditions
Information & Resources
The information within the following FAQ section is intended to be utilized as an information resource, not for diagnostic purposes. If you have any questions regarding any of the following eye conditions or believe that you may be experiencing symptoms of an acute or chronic eye condition you can contact our affiliated Optometry office at Gordon Eye Associates.
A Cataract is an eye condition characterised by the clouding of the lens of the eye. Normally, light passes through the clear lens and is focused onto the Retina. However, the natural aging process can cause the lens to become cloudy. The Cataract or cloudy lens blocks the passage of light through the eye and causes distorted or blurred vision, glare, or difficulty seeing in poor lighting conditions.
Cataract surgery is the most common operation in the world. In the United States, more than 2.7 million procedures are performed annually. There are 20.5 million cases of early cataracts among Americans aged 40 and older, and 50 percent of people older than 65 have developed significant cataracts according to the National Institutes of Health.
Glaucoma is actually a group of eye conditions that lead to damage of the optic nerve (the nerve fiber that carries information from the eye to the brain), which can then lead to vision loss and the possibility of blindness. Optic nerve damage usually occurs in the presence of high intraocular pressure, but glaucoma can occur with normal or even below-normal eye pressure.
There are two main forms of glaucoma: open-angle (which is the most common form and affects approximately 95% of individuals) and closed-angle. There are also several other varieties of glaucoma, including secondary, normal-tension, congenital, pseudoexfoliation syndrome, juvenile, neovascular, pigmentary, and irido-corneal-endothelial syndrome (ICE syndrome).
Worldwide, it is estimated that about 66.8 million people have visual impairment from glaucoma, with 6.7 million suffering from blindness. In the United States, approximately 2.2 million people age 40 and older have glaucoma, and of these, as many as 120,000 are blind due to the disease. The number of Americans with glaucoma is estimated to increase to 3.3 million by the year 2020. Vision experts estimate that half of those affected may not know they have it because symptoms may not occur during the early stages of the disease. Glaucoma is a leading cause of blindness among African Americans and Hispanics in the United States. African Americans experience glaucoma at a rate of three times that of Caucasians and experience blindness four times more frequently. Between the ages of 45 and 64, glaucoma is fifteen times more likely to cause blindness in African Americans than in Caucasians.
High-risk factors for open-angle glaucoma, the most common form of the disease, include being an African American and over 40, having a family history of the disease, and being over 60 for the general population. Those who are very nearsighted, have a history of diabetes, have experienced eye injury or eye surgery, or take prescription steroids also have an increased risk of developing glaucoma. It has also been suggested that individuals with Japanese ancestry may be at a greater risk for normal-tension glaucoma and that those of Asian and Eskimo descent may have a greater risk for closed-angle glaucoma.
Open-angle glaucoma, by far the most common form, has no symptoms at first. At some point, side vision (peripheral vision) is lost and without treatment, total blindness will occur. Closed-angle glaucoma (acute glaucoma) results from a sudden, complete blocking of the fluid flowing out of the eye. Symptoms may include severe pain, nausea, vomiting, blurred vision, and seeing a rainbow halo around lights. Closed-angle glaucoma is a medical emergency and must be treated immediately or blindness could result rapidly. Currently, there is no “cure” for glaucoma; however, early diagnosis and treatment can control glaucoma before vision loss or blindness occurs.
There are several tests that can help your eye care professional detect glaucoma; these include a visual acuity test, visual field test, dilated eye exam, tonometry (which measures the pressure inside of the eye), and pachymetry (which uses ultrasonic waves to help determine cornea thickness). Individuals at high risk for glaucoma should have a dilated pupil eye examination, and a visual field test annually. Early treatment for open-angle glaucoma will usually begin with medications (pills, ointments, or eyedrops, for example) that either help the eye to drain fluid more effectively or cause it to produce less fluid. Several forms of laser surgery can also help fluid drain from the eye. Incisional surgery to create a new opening for fluid to drain is usually performed after the other treatment options have failed.
When a patient has glaucoma or is at high risk for developing the disease, physicians may document how the optic nerve changes over time by making drawings, taking photographs, or using a new technique called optic nerve imaging. Scanning laser polarimetry (GDx), confocal scanning laser ophthalmoscopy (Heidelberg Retinal Tomograph or HRT III), and optical coherence tomography (OCT) are all examples of optic nerve imaging techniques. The patient’s eye care professional will make the determination as to which method(s) to use. New research is focusing not only on lowering pressure inside the eye but is also exploring medications that will protect and preserve the optic nerve from the damage that causes vision loss as well as the role of genetic factors. There has been progress in understanding the genetics of glaucoma in the last few years. Genes have been found that are associated with congenital glaucoma, juvenile glaucoma, normal-tension glaucoma, adult-onset open-angle glaucoma, pigmentary glaucoma, and other conditions that are associated with secondary glaucoma.
More information about Glaucoma is available from the National Institutes of Health.
Age-related Macular Degeneration (AMD) is an eye condition causing clear vision to fail in millions of older people. When electrical signals from the retina (the inner layer of the eye that captures light and turns it into an electrical signal) are received by the brain through the optic nerve, they are translated into images Age-related Macular Degeneration is traditionally described as a form of the disease which affects individuals over the age of 55 years. However, we have recently discovered that a significant number of these individuals may have a major genetic component that contributes to the disease. There are 2 types of AMD, dry and wet. Dry AMD is more common, causing about 90% of AMD. It can develop so gradually that in the beginning stages you might not notice changes in vision. Wet AMD is less common (about 10% of cases) but is more severe and may progress more rapidly.
Dry Macular Degeneration, in which the cells of the macula slowly begin to break down, is diagnosed in 90 percent of the cases. Yellow deposits called “drusen” form under the retina between the retinal pigmented epithelium (RPE) and Bruch’s membrane, which supports the retina. Drusen deposits are “debris” associated with compromised cell metabolism in the RPE and are often the first sign of Macular Degeneration. Eventually, there is a deterioration of the macular regions associated with the drusen deposits resulting in a spotty loss of “straight-ahead” vision.
Wet Macular Degeneration occurs when abnormal blood vessels grow behind the macula, then bleed. There is a breakdown in Bruch’s membrane, which usually occurs near drusen deposits. This is where the new blood vessel growth occurs (neovascularization). These vessels are very fragile and leak fluid and blood (hence ‘wet’), resulting in scarring of the macula and the potential for rapid, severe damage. “Straight ahead” vision can become distorted or lost entirely in a short period of time, sometimes within days. Wet macular degeneration accounts for approximately 10% of the cases, however it results in 90% of the legal blindness.
What does Macular Degeneration do to your vision?
Macular degeneration is the imprecise historical name given to that group of diseases that causes sight-sensing cells in the macular zone of the retina to malfunction or lose function and results in debilitating loss of vital central or detail vision.
What are the Symptoms of Macular Degeneration?
Macular Degeneration can cause different symptoms in different people. Sometimes only one eye loses vision while the other eye continues to see well for many years. The condition may be hardly noticeable in its early stages. But when both eyes are affected, reading and close up work can become difficult.
One of the easiest ways to screen for age-related macular degeneration (AMD) is to use an Amsler grid. An Amsler grid is a chart with lines and a dot at the center. Your doctor can give you an Amsler grid to use at home. For dry AMD (age-related macular degeneration), check your vision in each eye every day or as often as your doctor advises. It only takes a few seconds.
If you are post-menopausal, you should consult with your physician concerning estrogen replacement therapy. This may have a favorable impact upon cholesterol lipid levels that play a role in worsening the disease. Develop healthy habits! If you smoke, QUIT SMOKING! Exercising, maintaining normal blood pressure, cholesterol levels and eating a healthy diet is a step in the right direction. Eat food and-or supplements rich in vitamin E,C and Lutein. Lutein is a plant antioxidant found in high quantities in spinach, kale and other dark green, leafy vegetables. People who eat fish and green leafy vegetables may be at lower risk of AMD. There is no treatment for early dry AMD, although a special combination of supplements (zinc and antioxidant vitamins) may slow progression in some people with more advanced disease. Early intervention for wet AMD can delay progression.
More information is available from the National Institutes of Health.
Diabetic Retinopathy is the medical term for one of the most common diabetic eye conditions. Diabetic retinopathy is the leading cause of blindness in American adults. It damages the blood vessels in the retina, the light-sensitive nerve tissue in your eye that sends visual images to your brain. Blurred vision or temporary blindness can occur when blood vessels weaken, bulge and leak fluid into surrounding tissue, causing swelling – a condition called macular edema. Abnormal new blood vessels may often, grow on the retina, where they can bleed into the eye and block vision.
As the disease progresses, the retina can detach from the eye, resulting in permanent blindness. Irreversible vision loss can be prevented with early detection and treatment. This is just one of the reasons it is so important to have your eyes checked on a regular basis. In addition to testing your vision, we will look for any signs of eye disease.
Retinal damage happens slowly. Your retinas have tiny blood vessels that are easy to damage. Having high blood glucose and high blood pressure for a long time can damage these tiny blood vessels. First, these tiny blood vessels swell and weaken. Some blood vessels then become clogged and do not let enough blood through. At first, you might not have any loss of sight from these changes. This is why you need to have a comprehensive eye exam once a year even if your sight seems fine. As diabetic retinal problems get worse, new blood vessels may grow. These new blood vessels are weak. They break easily and leak blood into the vitreous of your eye. The leaking blood keeps light from reaching the retina.
You may see floating spots or almost total darkness. Sometimes the blood will clear out by itself, but you might need surgery to remove it. Over the years, the swollen and weak blood vessels can form scar tissue and pull the retina away from the back of the eye. If the retina becomes detached, you may see floating spots or flashing lights. You may feel as if a curtain has been pulled over part of your vision. A detached retina can cause loss of sight or blindness if you don’t take care of it right away.
More information is available from the National Institutes of Health.
The retina is the light-sensitive tissue at the back of the eye that sends images to the brain. Normally, the retina lies against the back of the eye where blood vessels furnish it with oxygen and nutrients. Tears in the retina may impair vision and lead to a detached retina. A detached retina occurs when the retina pulls away from the inside wall of the eye. When this happens vision becomes blurred, shaded or distorted. Left untreated, retinal detachment almost always causes permanent vision loss in the affected eye. Retinal detachment and tears may be caused by eye injury, the aging process, tumors, cataract surgery, eye disease or extreme nearsightedness.
More information is available from the National Institutes of Health.
Many times in our lifetime, we will experience a “foreign body sensation” in our eye. That usually happens if the wind blows dust, an allergen or a foreign body into our eye or under an eyelid. This should not be dismissed as just an uncomfortable feeling. It needs to be remedied. It cannot be allowed to linger or fester. For many, the feeling of grittiness, dryness, burning or stinging or even excessive tearing cannot be relieved simply, or with over the counter methods. It may be the sign of chronic eye conditions known as dry eye syndrome. Yes, even tearing eyes are a sign of dry eye.
The tears your eyes produce are necessary for overall eye health and clear vision. Dry eye means that your eyes do not produce enough tears or that you produce tears that do not have the proper chemical composition. Dry eye is more common as we age. It can also be caused by blinking or eyelid problems, medications like antihistamines, oral contraceptives, and antidepressants, a dry climate, wind and dust, general health problems like arthritis or Sjogren’s syndrome and chemical or thermal burns to your eyes.
Any condition that reduces the production, alters the composition or impedes the distribution of the preocular tear film (POTF) may cause a noticeable irritation to the structures of the front surface of the eye and a degradation of vision. These conditions are often related to problems with the structure or function of the eyelids, cornea, or conjunctiva. Depending upon the severity of symptoms, individuals may be limited in their ability to see clearly and comfortably and may be at increased risk of developing secondary infection or chronic inflammation that may not respond to treatment.
More information is available from the National Institutes of Health.
As we get older we expect to have problems with our eyes, so we tend to ignore them. One minor symptom that can cause a bigger problem, if not treated, is the occurrence of floaters and flashes. These are those tiny lights that seem to blink through your vision and that you can never catch when you direct your focus toward them. Almost everyone sees floaters at some time, but they can occur more frequently and become more noticeable as we get older.
Floaters caused by posterior vitreous detachment are more common in people who:
• Are nearsighted
• Have undergone cataract surgery
• Have had certain types of laser surgery
• Have had inflammation of the eye
Because floaters or flashes can be an indication of a serious problem, you should contact our doctor when:
• You see floaters for the first time
• You notice an increase in the number or size of floaters
• You experience the sudden onset of flashes
In most cases, no serious problems are found, but a complete eye examination is important. If there is damage to the retina, it needs to be diagnosed and treated immediately to prevent vision loss.
More information about Floaters & Flashers is available from the National Institutes of Health.
Amblyopia “lazy eye” are eye conditions that affects about four million people in the United States. It occurs when, for one of several reasons, one eye is used less than the other. If one eye is crossed or turns out, the individual sees double, so he or she learns to “shut off” or ignore that eye. If the two eyes are very different, one nearsighted and the other farsighted, the same thing can occur. After a while, vision in the unused eye is reduced.
For many years it was thought that amblyopia, or “lazy eye” – when one eye sees poorly and cannot be helped with corrective lenses – was a permanent condition unless it was detected and treated before the age of six. Many optometrists no longer accept this, believing that even adults can improve their sight – if not completely correct their lazy eye – through special therapy.
The American Optometric Association agrees that current research proves the old theory wrong. The success rate does drop off as one gets older, but the cut-off at age six is arbitrary. Age should not be a barrier, though the longer the condition has existed the more difficult it becomes to treat.
Treatment varies depending on the extent of the condition, the patients’ age, and the optometrist. Small children often have their stronger eye patched for several hours a day. This stimulates the use of the weak eye while they perform exercises such as coloring, cutting things out and tracing.
Vision therapy – usually several hours a week, in the doctor’s office and at home – will often correct the underlying reason for the lazy eye. Very small children can improve in a month or two; older children may take several months to a year to respond.
With adults, treatment is basically the same, but it takes longer. Adults may not wear a patch at all if vision is very poor, or only for an hour or two at home while doing fine tasks such as coloring in the 0’s of a newspaper. Patients do exercises designed to improve focusing, tracking, and spatial judgment.
Many times after treatment, 50 percent of the older children and adults see as well or almost as well with their lazy eye as with their normal eye, and four out of five of the rest at least show improvement. Results are permanent when both the amblyopia and the underlying problem are corrected. When the latter can’t be treated, patients should continue the exercises on a less-frequent basis and visit their optometrist periodically so that the eye does not weaken again.
More information about Amblyopia (Lazy Eye) is available from the National Institutes of Health.
Strabismus is a visual problem in which the eyes are not aligned properly and point in different directions. One eye may look straight ahead, while the other eye turns inward, outward, upward or downward. The eye turn may be constant, or it may come and go. Which eye is straight or misaligned may switch or alternate.
Strabismus are common eye conditions among children. About 4 percent of all children in the United States have strabismus. It can also occur later in life. Strabismus occurs equally in males and females. It may run in families; however, many people with strabismus have no relatives with the problem. The exact cause of strabismus is not fully understood. In some cases, strabismus may be due to problems with the muscles controlling eye movement. Six eye muscles that control eye movement are attached to the outside of each eye. In each eye, one muscle moves in the eye to the right, and one muscle moves the eye to the left. The other four muscles move it up or down and at an angle.
To line up and focus both eyes on a single target, all of the muscles in each eye must be balanced and working together. In order for the eyes to move together, the muscles in both eyes must be coordinated. The brain controls these muscles. With normal vision, both eyes aim at the same spot. The brain then combines the two pictures into a single, three-dimensional image. This three-dimensional image gives us depth perception. When one eye is out of alignment, two different pictures are sent to the brain. In a young child, the brain learns to ignore the image of the misaligned eye and sees only the image from the straight or better-seeing eye. The child then loses depth perception.
Adults who develop strabismus often have double vision because their brains have already learned to receive images from both eyes and cannot ignore the image from the turned eye. A child generally does not see double. In some cases, strabismus may result from problems in the brain. Sometimes, a child’s brain may not be correctly combining the two images it receives from the eyes. In rare cases, a tumor may affect how the brain processes visual information. Often children experience strabismus as a result of problems that can be easily treated with glasses.
Low vision can be caused by numerous eye conditions and is impaired vision that cannot be fully restored by surgery, medical treatments, or conventional eyeglasses or contact lenses. Low vision is not blindness. You are not alone; over 15 million Americans have some form of visual impairment. Our goal is to help you make the most of the eyesight you have so you can do more of the things you need and want to do — whether it’s reading a book, writing a letter, shopping, watching television or doing crafts.
When an individual’s eyesight can not be corrected to better than 20/200 with lenses, then he/she is diagnosed as having low vision. Macular degeneration, diabetic retinopathy, and genetic diseases are just some of the causes of this diminished vision. Unfortunately, many people are told that nothing can be done. While there may not be a cure, we can design and prescribe low vision systems for many of these individuals. Bioptic telescopes and microscopes are mounted in a pair of glasses to allow many of them to resume reading, cooking, hobbies, playing cards and in some cases driving – greatly improving their lifestyles.
More information about Low Vision is available from the National Institutes of Health.
Computer Vision Syndrome (CVS) is complex eye conditions and vision problems related to near work which are experienced during, or related to computer use. CVS is characterized by visual symptoms which result from interaction with a computer display or its environment. In most cases, symptoms occur because the visual demands of the task exceed the visual abilities of the individual to comfortably perform the task. Computer Vision Syndrome (CVS) affects three out of four computer users. It is a series of symptoms related to extended periods of computer usage. Although it is no cause for panic, measures can be taken to relieve symptoms of CVS.
CVS can appear as a variety of symptoms. Headaches, eye strain, neck and backaches, sensitivity to light, blurred vision, double vision, and dry or irritated eyes are all possible problems related to CVS. Any computer user can develop CVS. Your vision, your computer, and the environment where you use your computer are all factors that can lead to CVS. There are many aspects of computers and the work environment in which they are used which may cause or contribute to the development of eye or vision difficulties. To obtain optimum visual comfort and work efficiency, all computer operators who could benefit from a visual correction should wear it. One way to help ensure this is to remove financial barriers to the employee for obtaining an eye examination and when needed, treatment for eye conditions and vision problems. This can often be accomplished by having an employer or third party sponsored program which provides eye care services for employees who work at computers.
As part of an eye care program for computer operators, it may be necessary to determine whether any treatment, usually in the form of eyeglasses, is specific to the computer task or whether the same glasses or treatment would be required for general vision needs. This may establish whether the employee is eligible to receive occupationally related eye care services under the program.
Whether particular eye conditions require correction with eyeglasses or other treatment depends upon the clinical findings and the judgment of the examining doctor. However, the following criteria are recommended to help determine whether the care provided is computer related. These criteria are based upon the individual diagnosis and/or prescribed treatment. Since it is necessary for computer operators to have an eye and vision examination to determine whether these criteria are met, it is recommended that an examination be provided as part of the computer eye care program.
More information about Low Vision is available from the American Opthalomic Association.
Conjunctivitis, sometimes referred to as pink eye, is an infection or inflammation of the conjunctiva – the thin, protective membrane that covers the surface of the eyeball and inner surface of the eyelids. It can be caused by bacteria, viruses and other germs that are transmitted to the eye through contaminated hands, towels, and eye makeup or extended wear contacts. These eye conditions can also result from exposure to irritants such as chemicals, smoke or dust; or by pollen and other allergens. It is not uncommon for conjunctivitis to accompany a cold or flu.
Bacterial or viral conjunctivitis is contagious and tends to be prevalent in daycare centers and schools. It can spread by direct person-to-person contact, in airborne droplets that are coughed or sneezed, or from sharing makeup, towels, and washcloths. Its hallmark sign is redness in the white of the eye that may be accompanied by increased tearing and/or a discharge that is watery or thick with mucus and pus and causes the eyelids to stick together. Although usually a minor problem that improves within two weeks, some types can develop into serious corneal inflammation and vision loss if not treated. If you wear contact lenses and suspect you have conjunctivitis, discontinue wearing your contacts until the condition clears; you may also need to replace your contact lenses to prevent recurrence.
There are four primary types:
Bacterial conjunctivitis can affect one or both eyes and is usually accompanied by a heavy, yellow discharge that may cause the eyelids to stick together in the morning. Caused by a variety of bacteria, bacterial conjunctivitis is treated with antibiotic eye drops and typically resolves within 5 days. If there is concurrent inflammation of the eyelids, your eye care provider may also recommend an eyelid scrub to remove bacteria and dried mucous from the lid margin.
Viral conjunctivitis is often caused by adenoviruses, the family responsible for upper-respiratory illnesses such as colds, but can also result from herpes simplex and other viruses. This type can also affect either one or both eyes, and usually causes a lighter discharge. Although viral conjunctivitis usually produces a superficial case that clears on its own within two weeks, you should still see your eyecare provider to ensure it doesn’t lead to a more serious infection that can involve the cornea. Antibiotics are ineffective for viral conjunctivitis. Artificial tears may be used, or your doctor may recommend a topical anti-inflammatory drop to relieve discomfort. Topical or oral anti-herpetic medications can help suppress herpes viral infections.
Allergic conjunctivitis results from a response to airborne pollen, dust, smoke, or environmental agents. Both eyes are usually affected and may itch, tear excessively and discharge a stringy mucous. You may also have other allergic reactions, such as a runny or itchy nose. Depending on the severity, your eye doctor may prescribe topical drops that are effective in relieving the itching and discomfort. A very specific kind of allergic conjunctivitis may occur in contact lens wearers, especially if they do not clean the lenses well or if the lenses are not replaced often enough. Several treatments are available for this condition, including prescription allergy drops, changing contact lens solutions to keep the lenses cleaner, and changing to lenses that are replaced more frequently such as daily disposable contacts.
Chemical conjunctivitis is caused by exposure to irritating liquids, powders, or fumes and requires immediate action. Common irritants in include chlorine, detergents, fuels, ammonia, smoke and pesticides. First, flush the eye with cold water continuously for 15 minutes, then have the eyes evaluated by your eye doctor. For minor irritants such as chlorine, often artificial tears will effectively resolve the irritation. For chemicals burns from a strong acid or base, emergency medical treatment is needed.
More information about Pink Eye is available from the National Institutes of Health.
Allergies affect over 20% of the general population and are on the rise in many developed countries. The specific reason for the increasing prevalence of allergies has not been determined; some believe it is due to the effects of pollution in urban areas while others consider that modern lifestyles don’t allow for enough childhood exposure to allergens to become acclimated to them.
Eye allergies are no different than allergies that affect your sinuses, nose or lungs. When an allergen comes in contact with your eyes, your body releases histamine – a chemical produced in reaction to a substance that the immune system can’t tolerate. Special cells called mast cells make histamine. These cells are present throughout the body but are highly concentrated in the eyes. Location of allergy symptoms depends somewhat on where the allergen has come into contact with your body. Ocular allergens tend to be airborne (as are most other allergens).
The most frequent allergic triggers include:
• Pet hair or dander
Some triggers irritate the eyes but are not true allergies:
• Cigarette smoke
• Diesel Exhaust