Eye Facts

What are Vision Impairment and Legal Blindness?
Common Eye Diseases in Adults
Preventing Eye Injuries
Selecting Sunglasses

What is Vision Impairment and Legal Blindness?

Over three million people in the United States do not have normal vision even with eyeglasses or corrective lenses. These people are considered visually impaired. Visual impairment may be caused by a number of eye diseases, including age-related macular degeneration, diabetic retinopathy, glaucoma and cataracts, as well as by inherited disorders and injuries.

Although many eye diseases can be diagnosed and treated by your ophthalmologist, some may result in unavoidable loss of central (reading) vision, peripheral (side) vision, or both. Accidents or genetic disorders may also produce vision loss which cannot be medically corrected.

Visual impairment can range from mild to severe. Federal regulations define a certain level of visual impairment as "legal blindness" not to be confused with total blindness. Most of the approximately one million Americans defined as "legally blind" retain some useful vision.

How is Sight Measured?

Central or reading vision is customarily measured using an eye chart. The results are recorded as a pair of numbers called "visual acuity". In the familiar 20/20 notation, the first number is the distance from which a normal eye should see the letter clearly. People with a visual acuity of 20/20 can see certain sized letters at a distance of 20 feet. An individual with a visual acuity of 20/60 can only see at 20 feet, letters which a healthy eye can identify at 60 feet. The larger the second number, the lower your visual acuity.

Side vision - which can be even more important than central or reading vision for many daily activities-can also be measured by an ophthalmologist. Normal eyes can recognize objects over an area measuring at least 140 degrees (almost half a circle). A person with a much narrower range of side vision may have trouble walking or recognizing people in a large room, even when his or her central vision is excellent.

What is Legal Blindness?

When central vision is 20/200 or worse in your better eye, or your side vision is narrowed to 20 degrees or less in your better eye, you are considered legally blind even though you may still have some useful vision. People with this degree of impairment may qualify for certain government benefits and receive assistance from public and private organizations.

What is Visual Impairment?

If neither of your eyes can see better than 20/60 without improvement from eyeglasses or corrective lenses, you may be defined as visually impaired. Limitation of side vision, abnormal color vision, double vision, poor night vision, and loss of vision in one eye may also determine visual impairment.

What is low vision?

If ordinary eyeglasses, contact lenses or intraocular lens implants don't give you clear vision, you are said to have low vision. Don't confuse this condition with blindness. People with low vision still have useful vision that can often be improved with visual devices.

Whether your visual impairment is mild or severe, low vision generally means that your vision does not meet your needs. Using visual devices to improve your vision usually begins after your ophthalmologist has completed medical or surgical treatment or determined that such treatments will not improve your vision.

What causes low vision?

Though most often experienced by the elderly, people of all ages may be affected. Low vision can occur from birth defects, inherited diseases, injuries, diabetes, glaucoma, cataract and aging.

The most common cause is macular degeneration, a disease of the retina, the inner layer of the eye that senses light and allows you to see. Macular degeneration causes damage to central vision. It does not cause total blindness, because side (peripheral) vision is not affected.

Are there different types of low vision?

Yes. Although reduced central or reading vision is most common, low vision may also result from decreased side (peripheral) vision, or a loss of color vision. Or, your eye might lose the ability to adjust to light, contrast or glare.

Different types of low vision may require different kinds of assistance. For example, people born with low vision have different needs from those who develop low vision later in life.

What is a low vision device?

A low vision device is an apparatus that improves vision. There is no one device that restores normal vision in all circumstances, so you may need different devices for different purposes. If possible, try a device before you buy it to see if it is useful for you.

There are two types of low vision devices: optical and non-optical.

Optical low vision devices

Optical low vision devices use lenses or combinations of lenses to provide magnification. They should not be confused with standard eyeglasses. There are five main kinds of optical devices:

Magnifying spectacles are stronger than ordinary glasses. When you use them, you need to hold your reading material very close; otherwise the print is out of focus. This may feel awkward at first, but you will become used to it. They are designed for close work, so magnifying spectacles leave both hands free to hold reading material.
Hand magnifiers are familiar to most people. With these, you can hold reading material at a normal distance. You can buy hand magnifiers in department or drug stores.
Stand magnifiers rest on the reading material. Some have a self-contained light source.
Telescopes are used for distance magnification. They may be hand held for viewing distant objects, or mounted in spectacles.
Closed-circuit television produces an enlarged image on a television screen. With adjustable magnification and contrast, a closed-circuit television is often easier to use than other devices.

Non-optical low vision devices

Large-print books, newspapers and magazines
Check-writing guides
Large playing cards
Enlarged telephone dials
High-contrast watch faces
Machines that talk (timers, clocks, computers)
Machines that scan print and read aloud

The simplest non-optical technique is getting closer to what you want to see. Holding reading material very close to your eyes or sitting as close as one foot from the television screen will not cause eye damage, contrary to popular belief.

Is lighting important for people with low vision?

Correct lighting is as important as a low vision device. With no eye disorder, a 60-year-old person may need twice the illumination he or she needed at 20 to comfortably perform the same task. Some lighting tips:

Place the light source close to your reading material for greatest visibility. High intensity lights with adjustable arms work well for this purpose.
Visors and hat brims block annoying overhead light
Absorptive lenses are useful in controlling glare.

What Can You Do About Low Vision?

Have your eye doctor help you understand its cause and learn whether the impairment is temporary, stable or likely to progress.

Make use of rehabilitation programs, devices, and supportive services offered by the Bucks County Association for the Blind and Visually Impaired. These include counseling, large print and audio publications, optical and electronics magnifiers, mobility training, and non-optical aids such as improved light devices, large-face clocks and special kitchen tools.

Ask your ophthalmologist to refer you to the Bucks County Association for the Blind and Visually Impaired for a low vision evaluation.

Continue seeing your ophthalmologist for regular checkups. Your eye disorder may change, so its treatment may also need to be changed. Because eyes can be affected by more than one disease, it is especially important that any new problems be detected and treated promptly in order to preserve your remaining sight.

Signs of Possible Eye Trouble in Adults

Any changes in the appearance of your eyes or vision should be investigated further. Some examples include:

Unusual trouble adjusting to dark rooms
Difficulty focusing on near or distant objects
Squinting or blinking due to unusual sensitivity to light or glare
Change in color of iris
Red-rimmed, encrusted or swollen lids
Recurrent pain in or around eyes
Double vision
Dark spot at the center of viewing
Lines that appear distorted or wavy
Excess tearing or "watery eyes"
Dry eyes with itching or burning
Seeing spots, ghost-like images

The following may be indications of potentially serious problems:

Sudden loss of vision in one eye
Sudden hazy or blurred vision
Flashes of light or black spots
Halos or rainbows around light
Curtain-like blotting out of vision
Loss of peripheral (side) vision

If you notice any signs of potential eye problems, see an eye doctor for a complete eye exam. Even if you have no signs, regular eye exams are recommended - especially for those with some chronic health conditions such as diabetes and high blood pressure. Early detection and treatment can be the key to preventing sight loss.

Common Eye Diseases in Adults

Age-related macular degeneration (AMD) is a leading cause of vision loss among older adults. The disease affects the macula, the central area at the back of the eye. As a result the ability to see fine details is impaired. Laser treatment can help control vision loss due to leaking blood vessels found in some cases of AMD - especially when treated early.
Cataract is a clouding of eye's lens. Many people 65 years of age and older have some degree of cataract. If a cataract causes vision loss that interferes with important activities, it can be surgically removed. This results in improved vision in most cases.
Diabetic retinopathy is a complication of diabetes. It causes blood vessels inside the eye swell and leak. New abnormal blood vessels may start to grow. The longer a person has diabetes, the greater the likelihood of retinopathy. Carefully controlling blood sugar levels helps lessen the risk of vision loss. Those with diabetes should have annual eye exams to ensure early detection and treatment to prevent vision loss.
Glaucoma is a disease that "silently" destroys the optic nerve, eventually causing vision loss. Treated early, most cases can be controlled, reducing the risk of vision loss and blindness. You are at high risk if you have a family history of glaucoma, are over 65, are African American and over 45, have diabetes, have had an eye injury or have been on long-term steroid drugs.

What Is Macular Degeneration?

Macular degeneration is a progressive eye condition affecting as many as 15 million Americans and millions more around the world. The disease attacks the macula of the eye, where our sharpest central vision occurs. Although it rarely results in complete blindness, it robs the individual of all but the outermost, peripheral vision, leaving only dim images or black holes at the center of vision.

There are several types of macular degeneration, but the fastest growing form is age-related macular degeneration (AMD). AMD is the number one cause of vision loss and legal blindness in adults over 60 in the U.S. As our population ages, and the "baby boomers" advance into their 50's and 60's, we will see a virtual epidemic of AMD. Perhaps 14%-24% of the U.S. population aged 65-74 years and 35% of people aged 75 years or more have the disease.

Although it rarely causes total blindness, age-related macular degeneration robs those affected of their sharp central vision and can dim contrast sensitivity and color perception. It destroys the clear, "straight ahead" central vision necessary for reading, driving, identifying faces, watching television, doing fine detailed work, safely navigating stairs and performing other daily tasks we take for granted. Peripheral vision may not be affected, and it is possible to see "out of the corner of your eye". The impact of developing AMD can be devastating to those who were independent and active prior to the onset of this cruel impairment. Their visual world gradually diminishes into a vague blur, making ordinary daily activities challenging.

There is no cure for AMD, but new treatments are available. The most effective treatment is Low Vision Rehabilitation. Training and special devices can promote independence and a return to favorite activities.

Types of AMD

There are two types of age related macular degeneration. One form is known as "wet" and the other is "dry". It is possible to experience both forms at the same time, in one or both eyes. It is not uncommon for a patient with the "dry" form to develop the "wet" form later. The onset and progression of either type do not follow any particular pattern. In its earliest stages, AMD can be difficult to diagnose. Sometimes it progresses so slowly that people do not notice a change in their vision. Years may go by before they see an ophthalmologist or eye care professional. In other cases, the deterioration is very rapid and can appear to happen overnight.

Ninety percent of people who have Macular degeneration have the "dry" type. In the dry form, there is a breakdown or thinning of the retinal pigment epithelial cells (RPE) in the macula. These RPE cells are important to the health of the retina. They are light sensitive and contain hundreds of photoreceptors. The death or degeneration of these cells is called atrophy. Hence, dry AMD is often referred to as atrophic AMD. It is characterized by the presence of drusen (dots of yellow crystalline deposits that develop within the macula) and thinning of the macula. Dry or atrophic MD reduces one's central vision and can effect color perception. Generally, the damage caused by the "dry" form is not as severe as that of the "wet" form. Unfortunately, there is no proven cure or treatment.

The "wet" form of AMD is the more severe type of macular degeneration. Although it afflicts only 10 percent of those who have the condition, it accounts for 90 percent of the blindness caused by this disease. With this type, the membrane underlying the retina thickens, and then breaks. The oxygen supply to the macula is disrupted and the body responds by growing new, abnormal blood vessels. These begin to grow through the breaks of the membrane behind the retina towards the macula, often raising the retina.

To visualize this, imagine the roots of a tree growing and spreading until they actually uproot a sidewalk. Then imagine rainwater seeping up throughout the cracks. These abnormal blood vessels (the "roots) tend to be very fragile. They often grow, leak or bleed, causing scarring of the macula. This damage to the macula results in rapid central vision loss. Once this vision is destroyed, it cannot be restored.

Most patients report that their first sign of AMD was the rapid onset of prolonged, distorted vision. Straight lines like telephone wires and door frames appear to be wavy. If you notice any distorted or missing areas of vision, consult your ophthalmologist promptly.

Here are some examples of what a patient with macular degeneration might see. Figure 1 shows the typical wavy lines at the center of vision. Figure 2 shows the missing image that is characteristic either of wet macular degeneration or of the later stages of dry macular degeneration.

Figure 1

Figure 2

What is a cataract?

A cataract is a clouding of the normally clear lens of the eye. It can be compared to a window that is frosted or "fogged" with steam.

There are many misconceptions about cataract. It is:

Not a film over the eye;
Not caused by overusing the eyes;
Not a cancer;
Not spread from one eye to the other;
Not a cause of irreversible blindness.

Common symptoms of cataract include:

A painless blurring of vision;
Glare, or light sensitivity;
Frequent eyeglass prescription changes;
Double vision in one eye;
Needing brighter light to read;
Poor night vision;
Fading or yellowing of colors.

The amount and pattern of cloudiness within the lens can vary. If the cloudiness is not near the center of the lens, you may not be aware that a cataract is present.

What causes cataract?

The most common type of cataract is related to aging of the eye. Other causes of cataract include:

Family history;
Medical problems, such as diabetes;
Injury to the eye;
Medications, such as steroids;
Long-term, unprotected exposure to sunlight;
Previous eye surgery.

How is a cataract detected?

A thorough eye examination by your eye doctor can detect the presence and extent of a cataract, as well as any other conditions that may be causing blurred vision or discomfort.

There may be other reasons for visual loss in addition to the cataract, particularly problems involving the retina or optic nerve. If these problems are present, perfect vision may not return after cataract removal.

If such conditions are severe, removal of the cataract may not result in any improvement in vision. Your ophthalmologist can tell you how much visual improvement is likely.

How fast does a cataract develop?

How quickly the cataract develops varies among individuals, and may vary even between the two eyes. Most cataracts associated with aging progress gradually over a period of years.

Other cataracts, especially in younger people and people with diabetes, may progress rapidly over a few months and cause vision to worsen. It is not possible to predict exactly how fast cataracts will develop in any given person.

How is cataract treated?

Surgery is the only way your ophthalmologist can remove the cataract. However, if symptoms from a cataract are mild, a change of glasses may be all that is needed for you to function more comfortably.

There are no medications, dietary supplements, exercises or optical devices that have been shown to prevent or cure cataracts.

Protection from excessive sunlight may help prevent or slow the progression of cataracts. Sunglasses that screen out ultraviolet (UV) light rays or regular eyeglasses with a clear, anti-UV coating offer this protection.

What can I expect from cataract surgery?

Over 1.4 million people have cataract surgery each year in the United States, 95% without complications.

During cataract surgery, which is usually performed under local anesthesia as an outpatient procedure, the cloudy lens is removed from the eye. In most cases, the focusing power of the natural lens is restored by replacing it with a permanent intraocular lens implant.

Your ophthalmologist performs this delicate surgery using a microscope, miniature instruments and other modern technology.

Although it is a common misconception, lasers are not used to remove cataracts.

In approximately one-fifth of people having cataract surgery, the natural capsule that supports the intraocular lens will become cloudy. Laser surgery is used to open this cloudy capsule, restoring the clear vision.

After cataract surgery, you may return almost immediately to all but the most strenuous activities. You will have to take eye drops as your ophthalmologist directs. Several postoperative visits are needed to check on the progress of the eye as it heals.

Cataract surgery is a highly successful procedure. Improved vision is the result in over 90% of cases, unless there is a problem with the cornea, retina or op tic nerve. It is important to understand that complications can occur during or after the surgery, some severe enough to limit vision. As with any surgery, a good result cannot be guaranteed.

Diabetic Retinopathy

Diabetes can affect sight

If you have diabetes, your body does not use and store sugar properly. Diabetes can cause high blood-sugar levels, excessive thirst and urination. It can also cause changes in the body's blood vessels, the veins and arteries that carry blood throughout your body.

Because diabetes affects your body in these ways, it can affect vision by causing cataracts, glaucoma and, most importantly, damage to blood vessels inside the eye.

What is diabetic retinopathy?

Diabetic retinopathy is a complication of diabetes that is caused by changes in the blood vessels of the eye. The retina is a nerve layer at the back of the eye that senses light and helps to send images to your brain.

When blood vessels in the retina are damaged, they may leak fluid or blood, and grow fragile, brush-like branches and scar tissue. This can blur or distort the images that the retina sends to the brain.

Diabetic retinopathy is the leading cause of new blindness among adults in the United States. People with untreated diabetes are said to be 25 times more at risk for blindness than the general population.

The longer a person has diabetes, the more the risk of developing diabetic retinopathy increases. About 80% of the people who have had diabetes for at least 15 years have some blood vessel damage to their retina. People with Type I, or juvenile, diabetes are more likely to develop diabetic retinopathy at a younger age.

If you have diabetes, it's important to know that today, with improved methods of diagnosis and treatment, only a small percentage of people who develop retinopathy have serious vision problems.

How is diabetic retinopathy diagnosed?

The best protection against diabetic retinopathy is to have regular medical eye examinations by your eye doctor. Serious retinopathy can be present without any symptoms. With treatment, the disease can improve.

To find diabetic retinopathy, the ophthalmologist looks at the inside of the eye using an instrument called an ophthalmoscope. The pupils may need to be dilated (enlarged) with eye drops.

If your ophthalmologist finds diabetic retinopathy, he or she may order color photographs of the retina or a special test called fluorescein angiography to find out if you need treatment. Fluorescein angiography is a test where dye is injected in your arm and special photos of your eye are taken.

How is diabetic retinopathy treated?

In many cases treatment is not necessary, but you will need to continue having regular eye exams. In other cases, treatment is recommended to stop the damage of diabetic retinopathy and improve sight whenever possible.

Laser surgery may be performed in your ophthalmologist's office or an outpatient clinic. If diabetic retinopathy is detected early, laser surgery slows down vision loss. Even in the more advanced stages of the disease, it reduces the chance of severe visual impairment.

What is your part in treatment?

Your attention to medications and diet are essential. You must maintain blood sugar levels, avoid smoking and watch your blood pressure.

People with diabetes should schedule examinations by an ophthalmologist at least once a year. More frequent medical eye examinations may be necessary once diabetic retinopathy has been diagnosed.

What is glaucoma?

Glaucoma is a leading cause of blindness in the United States, especially for older people. But loss of sight from glaucoma is preventable if you get treatment early enough.

Glaucoma is a disease of the optic nerve. The optic nerve carries the images we see to the brain. Many people know that glaucoma has something to do with pressure inside the eye. The higher the pressure inside the eye, the greater the chance of damage to the optic nerve.

The optic nerve is like an electric cable containing a huge number of wires. Glaucoma can damage nerve fibers, causing blind spots to develop. Often people don't notice these blind areas until much optic nerve damage has already occurred. If the entire nerve is destroyed, blindness results.

Early detection and treatment by your ophthalmologist are the keys to preventing optic nerve damage and blindness from glaucoma.

What causes glaucoma?

Clear liquid, called the aqueous humor, flows in and out of the eye. This liquid is not part of the tears on the outer surface of the eye. You can think of the flow of aqueous fluid as a sink with the faucet turned on all the time.

If the "drainpipe" gets clogged, water collects in the sink and pressure builds up. If the drainage area of the eye - called the drainage angle - is blocked, the fluid pressure within the inner eye may increase, which can damage the optic nerve.

What are the different types of glaucoma?

Chronic open-angle glaucoma: This is the most common glaucoma. It occurs as a result of aging. The "drainpipe," or drainage angle of the eye, becomes less efficient with time, and pressure within the eye gradually increases.

If this increased pressure results in optic nerve damage, it is known as chronic open-angle glaucoma. Over 90% of adult glaucoma patients have this type of glaucoma.

Chronic open-angle glaucoma can damage vision so gradually and painlessly that you are not aware of trouble until the optic nerve is already badly damaged.

Angle-closure glaucoma: Sometimes the drainage angle of the eye may become completely blocked.

It is as though a sheet of paper floating near a drain suddenly drops over the opening and blocks the flow out of the sink. In the eye, the iris may act like the sheet of paper closing off the drainage angle.

When eye pressure builds up rapidly, it is called acute angle-closure glaucoma.

The symptoms include:

Blurred vision;
Severe eye pain;
Headache;
Rainbow haloes around lights;
Nausea and vomiting.

If you have any of these symptoms, call your ophthalmologist immediately. Unless an ophthalmologist treats acute angle-closure glaucoma quickly, blindness can result.

A more gradual and painless closing of the angle is called chronic angle-closure glaucoma. It occurs more frequently in people of African and Asian ancestry.

How is glaucoma detected?

Regular eye examinations by your ophthalmologist are the best way to detect glaucoma. An ophthalmologist is a medical eye doctor. Your ophthalmologist can detect and treat glaucoma.

During a complete and painless examination, your ophthalmologist will:

Measure your intraocular pressure
Inspect the drainage angle of your eye
Evaluate any optic nerve damage
Test the visual field of each eye

Some of these tests may not be necessary for every person. You may need to repeat these tests on a regular basis, to determine if glaucoma damage is increasing over time.

Who is at risk for glaucoma?

High pressure alone does not mean that you have glaucoma. Your ophthalmologist puts together many kinds of information to determine your risk for developing the disease.

The most important risk factors include:

Age
Near-sightedness
African ancestry
A family history of glaucoma; Past injuries to the eyes
A history of severe anemia or shock

Your ophthalmologist will weigh all of these factors before deciding whether you need treatment for glaucoma, or whether you should be monitored closely as a glaucoma suspect.

This means your risk of developing glaucoma is higher than normal, and you need to have regular examinations to detect the early signs of damage to the optic nerve.

How is glaucoma treated?

As a rule, damage caused by glaucoma cannot be reversed. Eye drops, pills and laser and surgical operations are used to prevent or slow further damage from occurring.

With any type of glaucoma, periodic examinations are very important to prevent vision loss. Because glaucoma can worsen without your being aware of it, your treatment may need to be changed over time.

Medicines

Glaucoma is usually controlled with eye drops taken several times a day, sometimes in combination with pills. These medications decrease eye pressure, either by slowing the production of aqueous fluid within the eye or by improving the flow leaving the drainage angle.

For these medications to work, you must take them regularly and continuously. It is also important to tell all of your doctors about the eye medications you are using.

Glaucoma medications can have side effects. You should notify your ophthalmologist immediately if you think you may be experiencing side effects.

Some eye drops may cause:

A stinging sensation
Red eyes
Blurred vision
Headaches
Changes in pulse, heartbeat or breathing

Pills sometimes cause:

Tingling of fingers and toes
Drowsiness
Loss of appetite
Bowel irregularities
Kidney stones
Anemia or easy bleeding

Laser surgery

Laser surgery treatments may be effective for different types of glaucoma. The laser is usually used in one of two ways.

In open-angle glaucoma, the drain itself is treated. The laser is used to enlarge the drain to help control eye pressure.

In angle-closure glaucoma, the laser creates a hole in the iris to improve the flow of aqueous fluid to the drain.

Operative surgery

When operative surgery is needed to control glaucoma, your ophthalmologist uses miniature instruments to create a new drainage channel for the aqueous fluid to leave the eye. The new channel helps to lower the pressure.

Though serious complications of modern glaucoma surgery are rare, they can occur, as with any surgery. Surgery is recommended only if your ophthalmologist feels that it is safer to operate than to allow optic nerve damage to continue.

What is your part in treatment?

Treatment for glaucoma requires a team" made up of both you and your doctor. Your ophthalmologist can prescribe treatment for glaucoma, but only you can make sure you take your eye drops or pills.

Never stop taking or change your medications without first consulting your ophthalmologist. Frequent eye examinations and tests are critical to monitor your eyes for any changes. Remember, it is your vision, and you must do your part to maintain it.

Loss of vision can be prevented

Regular medical eye exams may help prevent unnecessary vision loss. You should have an examination every 2 years OR MORE OFTEN

If a family member has glaucoma
If you are of African ancestry
If you have had a serious eye injury in the past
If you are taking steroid medications

Preventing Eye Injuries

Prevention is the first and most important step in avoiding eye injuries.

Over one million people suffer eye injuries each year in the United States. Almost 50% of these accidents occur at home, and 90% of them could have been prevented. Follow these simple procedures to prevent injury to your eyes:

In the house

Everyday products can sometimes cause serious burns when they touch the eyes.

Make sure that all spray nozzles are directed away from you before you pull the handle.
Read instructions carefully before using cleaning fluids, detergents, ammonia or harsh chemicals. Wash your hands thoroughly after use.
Use grease shields on frying pans to protect from spattering.
Wear safety goggles to shield your eyes from fumes and splashes when using powerful chemicals.
Use opaque goggles to avoid burns from sunlamps.

In the workshop

Many objects can fly into your eyes unexpectedly and cause an injury.

Think about the work you will be doing, and protect your eyes from flying fragments, fumes, dust particles, sparks and splashing chemicals before you begin work.
Read instructions thoroughly before using tools and chemicals and follow precautions for their use.
Protect yourself by wearing safety glasses.

Around children

Toys and games can be dangerous when used incorrectly.

Pay attention to your child's age and responsibility level when you buy toys and games. Avoid projectile toys such as darts, pellet guns, etc., which can hit the eye from a distance.
Supervise children when they are playing with toys or games that can be dangerous.
Teach children the correct way to handle items such as scissors and pencils.
BB and pellet guns should be considered as dangerous as regular firearms.

In the garden

Garden tools and chemicals are the cause of many outdoor eye injuries.

Keep everyone away when you use a lawnmower. Don't let anyone stand on the side or in front when you mow the lawn.
Pick up rocks and stones before going over them with your lawnmower. Stones can shoot out of the rotary blades, rebound off the curbs or walls and cause severe eye injuries. Wear safety glasses while mowing.
Avoid low hanging branches.
Make sure that pesticide spray-can nozzles are directed away from the face.
Wear safety glasses while using powered weed trimmers. The nylon cord can break loose and hit the eye. Keep all safety guards in place and keep others at a safe distance.

Around the car

Sparks and fumes can ignite rapidly and explode. Battery acid can cause serious eye injuries.

Put out all cigarettes and matches before opening the hood of the car. Use a flashlight - not a match or lighter - to look at the battery at night.
Keep protective goggles with your jumper cables and wear them.
Wear protective goggles for auto body repairs when grinding metal or striking metal against metal.

When you jump-start a car:

Make sure the cars are not touching each other;
Be sure the jumper cable clamps never touch each other;
Never lean over the battery when attaching cables;
Attach the positive cable (red) to the positive terminal of the dead battery first, then attach the other end of the positive cable to the good battery;
Attach the negative terminal of the good battery, and then attach the other end of the negative cable to a grounded area on the engine away from the negative terminal of the dead battery. Never attach a cable to the negative terminal of the dead battery.

In sports

Sports and recreational activities cause more than 31,000 eye injuries each year.

Wear protective safety glasses, especially for sports such as tennis, racquetball, squash, baseball and basketball.
Wear protective caps, helmets or face guards where appropriate, especially for sports such as ice hockey.

Around fireworks

All fireworks can be dangerous to people of all ages.
Never allow children to ignite fireworks.
Do not stand near others when lighting fireworks.

First aid for eye injuries

Correct treatment for an eye injury immediately following an accident can prevent loss of sight.

Specks in the eye

Do not rub your eye. Lift the upper lid over the lower lid allowing the lower lashes to brush the speck off the inside of the upper lid.

Blink a few times and let the eye move the particle out. If the speck remains, keep your eye closed and seek medical help.

Cuts of the eye and lid

Seek medical help immediately. Do not attempt to wash out the eye or remove an object stuck in the eye. Never apply pressure to the injured eye or eyelid. Be careful not to rub the eye.

Blows to the eye

Immediately apply an ice compress to the eye to reduce pain and swelling. A black eye or blurred vision can be a sign of damage inside the eye. See your ophthalmologist immediately.

Chemical burns

Flood the eye with water immediately using your fingers to keep the eye open as wide as possible.

Hold your head under a faucet or shower, or pour water gently into the eye from any container for at least fifteen minutes.

Roll the eyeball as much as possible to wash out the eye. Do not use an eye cup, or bandage the eye. Seek medical help immediately after these steps are taken.

Summary

When an accident involves the eye, you should get medical help immediately if there is pain or any question of eye or vision damage. Prompt, proper treatment of eye injuries can save vision. The most effective treatment for eye injuries is prevention.

Selecting Sunglasses

Sunglasses have been popular with people for years, both for comfort and as a fashion accessory.

Eye care professionals now believe there is another reason to wear sunglasses - to protect the long-term health of your eyes.

Results from a dozen studies over the last 10 years suggest that long hours in the sun without proper eye protection increase your chances of developing eye disease.

In 1988, a group of ophthalmologists studied 838 Chesapeake Bay fishermen who had spent years working on the water. The fishermen who wore no eye protection had three times as many cataracts as those who wore sunglasses or a brimmed hat. A cataract is a clouding of the eye's natural lens.

Based on this study and others, ophthalmologists now recommend that you wear UV- absorbent sunglasses and a brimmed hat whenever you're in the sun long enough to get a suntan or a sunburn, especially if you live at a high elevation or near the equator

Conflicting claims

Manufacturers have developed new sunglasses designed to protect eyes from the sun's harmful effects. They promise protection from ultraviolet light and other kinds of natural radiation. It is more important to protect your eyes from some kinds of light than others.

"Blocks 99% of ultraviolet rays"

You should always buy sunglasses with this feature. Long-term exposure to ultraviolet (UV) radiation in sunlight is linked to eye disease.

Both plastic and glass lenses absorb some UV light, but UV absorption can be improved by adding chemicals to the lens material during manufacturing or by applying special lens coatings.

Shop for sunglasses that block 99 or 100% of all UV light. Some manufacturers' labels say "UV absorption up to 4OOnm." This is the same thing as 100% UV absorption.

"Blocks 90% of infrared rays"

Infrared wavelengths are invisible (they are longer than light rays that you can see) and produce heat.

Sunlight has low levels of infrared rays, and the eye tolerates infrared well. Some sunglasses manufacturers make health claims for their products based on infrared protection, but research has not shown a close connection between eye disease and infrared rays.

"Blue-blocking"

Whether blue light is harmful to the eye is still controversial.

Lenses that block all blue light are usually amber and make your surroundings look yellow or orange.

The tint supposedly makes distant objects appear more distinct, especially in snow or haze. For this reason, amber sunglasses are popular among skiers, hunters, boaters and pilots.

"Polarized"

Polarized lenses cut reflected glare -sunlight that bounces off smooth surfaces like pavement or water. They can be particularly useful for driving and fishing.

Polarization has nothing to do with UV light absorption, but many polarized lenses are now combined with a UV-blocking substance. Check the label to make sure the lenses provide maximum UV protection.

"Mirror-coated"

Mirror finishes are thin layers of various metallic coatings on an ordinary lens. Although they do reduce the amount of visible light entering your eyes, do not assume they will fully protect you against UV radiation.

"Wraparound"

Wraparound glasses are shaped to keep light from shining around the frames and into your eyes.

Studies have shown that enough UV rays enter around ordinary eyeglass frames to reduce the benefits of protective lenses. Large-framed wraparound sunglasses can protect your eyes from all angles.

"Gradient"

Gradient lenses are permanently shaded from top to bottom or from top and bottom toward the middle.

Single-gradient lenses (dark on top and lighter on the bottom) can cut glare from the sky but allow you to see clearly below. They are useful for driving because they don't dim your view of the dashboard. But they're not as good on snow or at the beach, especially if they're clear on the bottom.

Double-gradient lenses (dark on top and bottom and lighter in the middle) may be better for sports where light reflects up off the water or snow, such as sailing or skiing.

Double-gradient lenses are not recommended for driving, because they make the dashboard appear dim.

"Photochromic"

A photochromic glass lens automatically darkens in bright light and becomes lighter in low light.

Most of the darkening takes place in about half a minute, while the lightening takes about five minutes. They come in a uniform or gradient tint.

Although photochromic lenses may be good UV-absorbent sunglasses (again, the label must say that), it takes time for them to adjust to different light conditions.

"Ground and polished"

Some non-prescription glasses are ground and polished when they are manufactured to improve the quality of the lenses. Non-prescription lenses that are not ground and polished will not hurt your eyes.

You do want to make sure that the lenses you buy are made properly. To judge the quality of non-prescription sunglasses, look at something with a rectangular pattern such as floor tile.

Hold the glasses at a comfortable distance and cover one eye. Move the glasses slowly from side to side, then up and down. If the lines stay straight, the lenses are fine. If the lines wiggle, especially in the center of the lens, try another pair.

"Impact resistant"

All sunglasses must meet impact standards set by the Federal Food and Drug Administration.

No lens is truly unbreakable, but plastic lenses are less likely than glass lenses to shatter when hit by a ball or stone.

Most non-prescription sunglass lenses are plastic. Polycarbonate plastic, used in many sports sunglasses, is especially tough but scratches easily. If you buy polycarbonate lenses, look for ones with scratch-resistant coatings.

Lens darkness

A medium lens is good for day-to-day wear, but if you use the glasses for very bright conditions, choose a darker lens.

The color and the degree of darkness do not tell you anything about the lenses' ability to block UV light.

Those at special risk

There are some people who are at greater risk for UV- related eye damage. People with certain eye diseases, such as macular degeneration or retinal dystrophies, need to protect their eyes whenever they go outside, no matter how briefly.

Cataract surgery patients

One million Americans have cataract surgery each year. During this procedure, the eye's natural lens is removed, leaving the eye more vulnerable to UV light.

During or after cataract surgery, the natural lens is usually replaced by an intraocular lens (IOL). Older intraocular lenses absorb much less IJY light than ordinary glass or plastic eyeglass lenses.

Manufacturers of lOLs now make many of their products Uv absorbent.

If you have had cataract surgery and your IOL is not the newer UV- absorbent type, you may want to wear sunglasses and a hat for added protection.

Contact lens wearers

Contact lenses by themselves will not protect your eyes from IW light. Many types of contact lenses are available with Uv protection.

If you do not have contact lenses that absorb Uv light, you still need to pro-tect your eyes with sunglasses.

Photosensitizing drugs

Photosensitizing drugs - drugs that make your skin more sensitive to light - can make your eyes more sensitive to light as well.

You should discuss precautions with your ophthalmologist if you are taking any of the following drugs:

Psoralens (used in treating psoriasis);
Tetracycline;
Doxycycline;
Allopurinol;
Phenothiazine.

Wear UV-absorbent sunglasses and a hat whenever you go outside for as long as you take the drug.

Special situations

Ordinary sunglasses, even the best, cannot protect your eyes from certain intense light sources. Arc welding, tanning lights, snowfields or gazing directly at the sun (especially during a solar eclipse) can damage your eyes.

Looking at any of these light sources without adequate protection can cause a painful corneal condition called photokeratitis or even a permanent loss of central vision.

Cost

The best sunglasses offer 100% UV absorption, the best optical quality and are the least likely to break. Yet they don't have to be expensive.