Cataract Defined
What is a cataract?
A cataract is a clouding of the lens in the eye that affects vision. Most cataracts are related to aging. Cataracts are very common in older people. By age 80, more than half of all Americans either have a cataract or have had cataract surgery.
A cataract can occur in either or both eyes. It cannot spread from one eye to the other
What is the lens?
The lens is a clear part of the eye that helps to focus light, or an image, on the retina. The retina is the light-sensitive tissue at the back of the eye.
In a normal eye, light passes through the transparent lens to the retina. Once it reaches the retina, light is changed into nerve signals that are sent to the brain.
The lens must be clear for the retina to receive a sharp image. If the lens is cloudy from a cataract, the image you see will be blurred.
Are there other types of cataract?
Yes. Although most cataracts are related to aging, there are other types 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.
Causes and Risk Factors
What causes cataracts?
The lens lies behind the iris and the pupil (see diagram). It works much like a camera lens. It focuses light onto the retina at the back of the eye, where an image is recorded. The lens also adjusts the eye's focus, letting us see things clearly both up close and far away. The lens is made of mostly water and protein. The protein is arranged in a precise way that keeps the lens clear and lets light pass through it.
But as we age, some of the protein may clump together and start to cloud a small area of the lens. This is a cataract. Over time, the cataract may grow larger and cloud more of the lens, making it harder to see.
Researchers suspect that there are several causes of cataract, such as smoking and diabetes. Or, it may be that the protein in the lens just changes from the wear and tear it takes over the years.
How can cataracts affect my vision?
Age-related cataracts can affect your vision in two ways:
Clumps of protein reduce the sharpness of the image reaching the retina.
The lens consists mostly of water and protein. When the protein clumps up, it clouds the lens and reduces the light that reaches the retina. The clouding may become severe enough to cause blurred vision. Most age-related cataracts develop from protein clumpings.
When a cataract is small, the cloudiness affects only a small part of the lens. You may not notice any changes in your vision. Cataracts tend to "grow" slowly, so vision gets worse gradually. Over time, the cloudy area in the lens may get larger, and the cataract may increase in size. Seeing may become more difficult. Your vision may get duller or blurrier.
The clear lens slowly changes to a yellowish/brownish color, adding a brownish tint to vision.
As the clear lens slowly colors with age, your vision gradually may acquire a brownish shade. At first, the amount of tinting may be small and may not cause a vision problem. Over time, increased tinting may make it more difficult to read and perform other routine activities. This gradual change in the amount of tinting does not affect the sharpness of the image transmitted to the retina.
If you have advanced lens discoloration, you may not be able to identify blues and purples. You may be wearing what you believe to be a pair of black socks, only to find out from friends that you are wearing purple socks.
When are you most likely to have a cataract?
The term "age-related" is a little misleading. You don't have to be a senior citizen to get this type of cataract. In fact, people can have an age-related cataract in their 40s and 50s. But during middle age, most cataracts are small and do not affect vision. It is after age 60 that most cataracts steal vision.
Who is at risk for cataract?
The risk of cataract increases as you get older. Other risk factors for cataract include:
Certain diseases such as diabetes.
Personal behavior such as smoking and alcohol use.
The environment such as prolonged exposure to sunlight.
What can I do to protect my vision?
Wearing sunglasses and a hat with a brim to block ultraviolet sunlight may help to delay cataract. If you smoke, stop. Researchers also believe good nutrition can help reduce the risk of age-related cataract. They recommend eating green leafy vegetables, fruit, and other foods with antioxidants.
If you are age 60 or older, you should have a comprehensive dilated eye exam at least once every two years. In addition to cataract, your eye care professional can check for signs of age-related macular degeneration, glaucoma, and other vision disorders. Early treatment for many eye diseases may save your sight.
Symptoms and Detection
What are the symptoms of a cataract?
The most common symptoms of a cataract are:
Cloudy or blurry vision.
Colors seem faded.
Glare. Headlights, lamps, or sunlight may appear too bright. A halo may appear around lights.
Poor night vision.
Double vision or multiple images in one eye. (This symptom may clear as the cataract gets larger.)
Frequent prescription changes in your eyeglasses or contact lenses.
These symptoms also can be a sign of other eye problems. If you have any of these symptoms, check with your eye care professional.
How is a cataract detected?
Cataract is detected through a comprehensive eye exam that includes:
Visual acuity test. This eye chart test measures how well you see at various distances.
Dilated eye exam. Drops are placed in your eyes to widen, or dilate, the pupils. Your eye care professional uses a special magnifying lens to examine your retina and optic nerve for signs of damage and other eye problems. After the exam, your close-up vision may remain blurred for several hours.
Tonometry. An instrument measures the pressure inside the eye. Numbing drops may be applied to your eye for this test.
Your eye care professional also may do other tests to learn more about the structure and health of your eye.
Treatment
How is a cataract treated?
The symptoms of early cataract may be improved with new eyeglasses, brighter lighting, anti-glare sunglasses, or magnifying lenses. If these measures do not help, surgery is the only effective treatment. Surgery involves removing the cloudy lens and replacing it with an artificial lens.
A cataract needs to be removed only when vision loss interferes with your everyday activities, such as driving, reading, or watching TV. You and your eye care professional can make this decision together. Once you understand the benefits and risks of surgery, you can make an informed decision about whether cataract surgery is right for you. In most cases, delaying cataract surgery will not cause long-term damage to your eye or make the surgery more difficult. You do not have to rush into surgery.
Sometimes a cataract should be removed even if it does not cause problems with your vision. For example, a cataract should be removed if it prevents examination or treatment of another eye problem, such as age-related macular degeneration or diabetic retinopathy. If your eye care professional finds a cataract, you may not need cataract surgery for several years. In fact, you might never need cataract surgery. By having your vision tested regularly, you and your eye care professional can discuss if and when you might need treatment.
If you choose surgery, your eye care professional may refer you to a specialist to remove the cataract.
If you have cataracts in both eyes that require surgery, the surgery will be performed on each eye at separate times, usually four to eight weeks apart.
Many people who need cataract surgery also have other eye conditions, such as age-related macular degeneration or glaucoma. If you have other eye conditions in addition to cataract, talk with your doctor. Learn about the risks, benefits, alternatives, and expected results of cataract surgery.
What are the different types of cataract surgery?
There are two types of cataract surgery. Your doctor can explain the differences and help determine which is better for you:
Phacoemulsification, or phaco. A small incision is made on the side of the cornea, the clear, dome-shaped surface that covers the front of the eye. Your doctor inserts a tiny probe into the eye. This device emits ultrasound waves that soften and break up the lens so that it can be removed by suction. Most cataract surgery today is done by phacoemulsification, also called "small incision cataract surgery."
Extracapsular surgery. Your doctor makes a longer incision on the side of the cornea and removes the cloudy core of the lens in one piece. The rest of the lens is removed by suction.
After the natural lens has been removed, it often is replaced by an artificial lens, called an intraocular lens (IOL). An IOL is a clear, plastic lens that requires no care and becomes a permanent part of your eye. Light is focused clearly by the IOL onto the retina, improving your vision. You will not feel or see the new lens.
Some people cannot have an IOL. They may have another eye disease or have problems during surgery. For these patients, a soft contact lens, or glasses that provide high magnification, may be suggested.
What are the risks of cataract surgery?
As with any surgery, cataract surgery poses risks, such as infection and bleeding. Before cataract surgery, your doctor may ask you to temporarily stop taking certain medications that increase the risk of bleeding during surgery. After surgery, you must keep your eye clean, wash your hands before touching your eye, and use the prescribed medications to help minimize the risk of infection. Serious infection can result in loss of vision.
Cataract surgery slightly increases your risk of retinal detachment. Other eye disorders, such as high myopia (nearsightedness), can further increase your risk of retinal detachment after cataract surgery. One sign of a retinal detachment is a sudden increase in flashes or floaters. Floaters are little "cobwebs" or specks that seem to float about in your field of vision. If you notice a sudden increase in floaters or flashes, see an eye care professional immediately. A retinal detachment is a medical emergency. If necessary, go to an emergency service or hospital. Your eye must be examined by an eye surgeon as soon as possible. A retinal detachment causes no pain. Early treatment for retinal detachment often can prevent permanent loss of vision. The sooner you get treatment, the more likely you will regain good vision. Even if you are treated promptly, some vision may be lost.
Talk to your eye care professional about these risks. Make sure cataract surgery is right for you.
Is cataract surgery effective?
Cataract removal is one of the most common operations performed in the United States. It also is one of the safest and most effective types of surgery. In about 90 percent of cases, people who have cataract surgery have better vision afterward.
What happens before surgery?
A week or two before surgery, your doctor will do some tests. These tests may include measuring the curve of the cornea and the size and shape of your eye. This information helps your doctor choose the right type of IOL.
You may be asked not to eat or drink anything 12 hours before your surgery.
What happens during surgery?
At the hospital or eye clinic, drops will be put into your eye to dilate the pupil. The area around your eye will be washed and cleansed.
The operation usually lasts less than one hour and is almost painless. Many people choose to stay awake during surgery. Others may need to be put to sleep for a short time.
If you are awake, you will have an anesthetic to numb the nerves in and around your eye.
After the operation, a patch may be placed over your eye. You will rest for a while. Your medical team will watch for any problems, such as bleeding. Most people who have cataract surgery can go home the same day. You will need someone to drive you home.
What happens after surgery?
Itching and mild discomfort are normal after cataract surgery. Some fluid discharge is also common. Your eye may be sensitive to light and touch. If you have discomfort, your doctor can suggest treatment. After one or two days, moderate discomfort should disappear.
For a few days after surgery, your doctor may ask you to use eyedrops to help healing and decrease the risk of infection. Ask your doctor about how to use your eyedrops, how often to use them, and what effects they can have. You will need to wear an eye shield or eyeglasses to help protect your eye. Avoid rubbing or pressing on your eye.
When you are home, try not to bend from the waist to pick up objects on the floor. Do not lift any heavy objects. You can walk, climb stairs, and do light household chores.
In most cases, healing will be complete within eight weeks. Your doctor will schedule exams to check on your progress.
Can problems develop after surgery?
Problems after surgery are rare, but they can occur. These problems can include infection, bleeding, inflammation (pain, redness, swelling), loss of vision, double vision, and high or low eye pressure. With prompt medical attention, these problems can usually be treated successfully.
Sometimes the eye tissue that encloses the IOL becomes cloudy and may blur your vision. This condition is called an after-cataract. An after-cataract can develop months or years after cataract surgery.
An after-cataract is treated with a laser. Your doctor uses a laser to make a tiny hole in the eye tissue behind the lens to let light pass through. This outpatient procedure is called a YAG laser capsulotomy. It is painless and rarely results in increased eye pressure or other eye problems. As a precaution, your doctor may give you eyedrops to lower your eye pressure before or after the procedure.
When will my vision be normal again?
You can return quickly to many everyday activities, but your vision may be blurry. The healing eye needs time to adjust so that it can focus properly with the other eye, especially if the other eye has a cataract. Ask your doctor when you can resume driving.
If you received an IOL, you may notice that colors are very bright. The IOL is clear, unlike your natural lens that may have had a yellowish/brownish tint. Within a few months after receiving an IOL, you will become used to improved color vision. Also, when your eye heals, you may need new glasses or contact lenses.
What can I do if I already have lost some vision from cataract?
If you have lost some sight from cataract or cataract surgery, ask your eye care professional about low vision services and devices that may help you make the most of your remaining vision. Ask for a referral to a specialist in low vision. Many community organizations and agencies offer information about low vision counseling, training, and other special services for people with visual impairments. A nearby school of medicine or optometry may provide low vision services.
Saturday, February 23, 2008
Visual impairment
Visual impairment can be defined as any chronic visual deficit that impairs everyday functioning and is not correctable by ordinary eyeglasses or contact lenses. Visual impairment can be mild or moderate but also includes total blindness or functional blindness where no useful vision remains. Although there have been important strides over the past few decades in the treatment and prevention of eye diseases that cause visual impairment, there are still many causes of vision loss for which there is no cure. Even with the best medical treatment, many Americans live with impaired vision. In the United States, where normal vision is 20/20, legal blindness is defined as visual acuity with best correction in the better eye worse than or equal to 20/200 or a visual field extent of less than 20 degrees in diameter. In many States, a visual acuity of less than 20/40 disqualifies a person from obtaining a driver's license, as do some visual field deficits. Research in visual impairment and blindness is aimed at developing and assessing new methods for the rehabilitation of visually impaired individuals through assistive technologies, training, and rehabilitation services and education.
Current estimates of the number of people who are visually impaired vary greatly by source and method of measurement, as well as by the inclusion criteria applied. Conservative estimates suggest that there are at least 3.5 to 5 million Americans who are visually impaired, and more than 1 million of these are legally blind. Because of the narrowly defined definitions of visual impairment, these figures undoubtedly underestimate the problem. However, many people experience functional limitations due to vision loss even though they do not meet the criteria for legal blindness. Even relatively mild impairment of vision can affect the performance of everyday tasks such as driving, reading, and walking. When more broadly defined as visual problems that hamper the performance and enjoyment of everyday activities, other recent estimates indicate that almost 14 million Americans suffer from visual impairment. Older adults represent the majority of the visually impaired population. Visual impairment is included among the 10 most prevalent causes of disability in the United States.
The leading causes of visual impairment are diseases that are common in elderly persons, including AMD, glaucoma, DR, cataract, and optic nerve atrophy. More than two-thirds of people with visual impairment are older than 65 years of age. It is estimated that there were almost 34 million Americans older than age 65 years in 1992 and that by 2030 this number will more than double. Visual impairment in elderly persons decreases independence, increases the risk of falls and fractures, and often leads to isolation and depression.
The leading causes of visual impairment in infants and children are retinopathy of prematurity, deficits in the visual centers of the brain, and structural ocular abnormalities such as cataract and retinal abnormalities. These conditions sometimes have a severe impact on children's quality of life, especially when vision impairment coexists with other impairments, and can have major consequences on education and future opportunities for employment. However, children, like adults, benefit significantly from coordinated and comprehensive services to ameliorate disability.
Current estimates of the number of people who are visually impaired vary greatly by source and method of measurement, as well as by the inclusion criteria applied. Conservative estimates suggest that there are at least 3.5 to 5 million Americans who are visually impaired, and more than 1 million of these are legally blind. Because of the narrowly defined definitions of visual impairment, these figures undoubtedly underestimate the problem. However, many people experience functional limitations due to vision loss even though they do not meet the criteria for legal blindness. Even relatively mild impairment of vision can affect the performance of everyday tasks such as driving, reading, and walking. When more broadly defined as visual problems that hamper the performance and enjoyment of everyday activities, other recent estimates indicate that almost 14 million Americans suffer from visual impairment. Older adults represent the majority of the visually impaired population. Visual impairment is included among the 10 most prevalent causes of disability in the United States.
The leading causes of visual impairment are diseases that are common in elderly persons, including AMD, glaucoma, DR, cataract, and optic nerve atrophy. More than two-thirds of people with visual impairment are older than 65 years of age. It is estimated that there were almost 34 million Americans older than age 65 years in 1992 and that by 2030 this number will more than double. Visual impairment in elderly persons decreases independence, increases the risk of falls and fractures, and often leads to isolation and depression.
The leading causes of visual impairment in infants and children are retinopathy of prematurity, deficits in the visual centers of the brain, and structural ocular abnormalities such as cataract and retinal abnormalities. These conditions sometimes have a severe impact on children's quality of life, especially when vision impairment coexists with other impairments, and can have major consequences on education and future opportunities for employment. However, children, like adults, benefit significantly from coordinated and comprehensive services to ameliorate disability.
macular degeneration
Age-Related Macular Degeneration (AMD) Defined
What is age-related macular degeneration?
Age-related macular degeneration (AMD) is a disease associated with aging that gradually destroys sharp, central vision. Central vision is needed for seeing objects clearly and for common daily tasks such as reading and driving.
AMD affects the macula, the part of the eye that allows you to see fine detail. AMD causes no pain.
In some cases, AMD advances so slowly that people notice little change in their vision. In others, the disease progresses faster and may lead to a loss of vision in both eyes. AMD is a leading cause of vision loss in Americans 60 years of age and older.
AMD occurs in two forms: wet and dry.
Where is the macula?
The macula is located in the center of the retina, the light-sensitive tissue at the back of the eye. The retina instantly converts light, or an image, into electrical impulses. The retina then sends these impulses, or nerve signals, to the brain.
What is wet AMD?
Wet AMD occurs when abnormal blood vessels behind the retina start to grow under the macula. These new blood vessels tend to be very fragile and often leak blood and fluid. The blood and fluid raise the macula from its normal place at the back of the eye. Damage to the macula occurs rapidly.
With wet AMD, loss of central vision can occur quickly. Wet AMD is also known as advanced AMD. It does not have stages like dry AMD.
An early symptom of wet AMD is that straight lines appear wavy. If you notice this condition or other changes to your vision, contact your eye care professional at once. You need a comprehensive dilated eye exam.
What is dry AMD?
Dry AMD occurs when the light-sensitive cells in the macula slowly break down, gradually blurring central vision in the affected eye. As dry AMD gets worse, you may see a blurred spot in the center of your vision. Over time, as less of the macula functions, central vision is gradually lost in the affected eye.
The most common symptom of dry AMD is slightly blurred vision. You may have difficulty recognizing faces. You may need more light for reading and other tasks. Dry AMD generally affects both eyes, but vision can be lost in one eye while the other eye seems unaffected.
One of the most common early signs of dry AMD is drusen.
What are drusen?
Drusen are yellow deposits under the retina. They often are found in people over age 60. Your eye care professional can detect drusen during a comprehensive dilated eye exam.
Drusen alone do not usually cause vision loss. In fact, scientists are unclear about the connection between drusen and AMD. They do know that an increase in the size or number of drusen raises a person's risk of developing either advanced dry AMD or wet AMD. These changes can cause serious vision loss.
Dry AMD has three stages, all of which may occur in one or both eyes:
Early AMD. People with early AMD have either several small drusen or a few medium-sized drusen. At this stage, there are no symptoms and no vision loss.
Intermediate AMD. People with intermediate AMD have either many medium-sized drusen or one or more large drusen. Some people see a blurred spot in the center of their vision. More light may be needed for reading and other tasks.
Advanced Dry AMD. In addition to drusen, people with advanced dry AMD have a breakdown of light-sensitive cells and supporting tissue in the central retinal area. This breakdown can cause a blurred spot in the center of your vision. Over time, the blurred spot may get bigger and darker, taking more of your central vision. You may have difficulty reading or recognizing faces until they are very close to you
Frequently Asked Questions about wet and dry AMD
Which is more common-the dry form or the wet form?
The dry form is much more common. More than 85 percent of all people with intermediate and advanced AMD combined have the dry form.
However, if only advanced AMD is considered, about two-thirds of patients have the wet form. Because almost all vision loss comes from advanced AMD, the wet form leads to significantly more vision loss than the dry form.
Can the dry form turn into the wet form?
Yes. All people who have the wet form had the dry form first.
The dry form can advance and cause vision loss without turning into the wet form. The dry form also can suddenly turn into the wet form, even during early stage AMD. There is no way to tell if or when the dry form will turn into the wet form.
The dry form has early and intermediate stages. Does the wet form have similar stages?
No. The wet form is considered advanced AMD.
Can advanced AMD be either the dry form or the wet form?
Yes. Both the wet form and the advanced dry form are considered advanced AMD. Vision loss occurs with either form. In most cases, only advanced AMD can cause vision loss.
People who have advanced AMD in one eye are at especially high risk of developing advanced AMD in the other eye.
Causes and Risk Factors
Who is at risk for AMD?
The greatest risk factor is age. Although AMD may occur during middle age, studies show that people over age 60 are clearly at greater risk than other age groups. For instance, a large study found that people in middle-age have about a 2 percent risk of getting AMD, but this risk increased to nearly 30 percent in those over age 75.
Other risk factors include:
Smoking. Smoking may increase the risk of AMD.
Obesity. Research studies suggest a link between obesity and the progression of early and intermediate stage AMD to advanced AMD.
Race. Whites are much more likely to lose vision from AMD than African Americans.
Family history. Those with immediate family members who have AMD are at a higher risk of developing the disease.
Gender. Women appear to be at greater risk than men.
Can my lifestyle make a difference?
Your lifestyle can play a role in reducing your risk of developing AMD.
Eat a healthy diet high in green leafy vegetables and fish.
Don't smoke.
Maintain normal blood pressure.
Watch your weight.
Exercise.
Symptoms and Detection
What are the symptoms?
Both dry and wet AMD cause no pain.
For dry AMD: the most common early sign is blurred vision. As fewer cells in the macula are able to function, people will see details less clearly in front of them, such as faces or words in a book. Often this blurred vision will go away in brighter light. If the loss of these light-sensing cells becomes great, people may see a small--but growing--blind spot in the middle of their field of vision.
For wet AMD: the classic early symptom is that straight lines appear crooked. This results when fluid from the leaking blood vessels gathers and lifts the macula, distorting vision. A small blind spot may also appear in wet AMD, resulting in loss of one's central vision.
How is AMD detected?
Your eye care professional may suspect AMD if you are over age 60 and have had recent changes in your central vision. To look for signs of the disease, he or she will use eye drops to dilate, or enlarge, your pupils. Dilating the pupils allows your eye care professional to view the back of the eye better.
AMD is detected during a comprehensive eye exam that includes:
Visual acuity test. This eye chart test measures how well you see at various distances.
Dilated eye exam. Drops are placed in your eyes to widen, or dilate, the pupils. Your eye care professional uses a special magnifying lens to examine your retina and optic nerve for signs of AMD and other eye problems. After the exam, your close-up vision may remain blurred for several hours.
Tonometry. An instrument measures the pressure inside the eye. Numbing drops may be applied to your eye for this test.
Treatment
How is wet AMD treated?
Wet AMD can be treated with laser surgery, photodynamic therapy, and injections into the eye. None of these treatments is a cure for wet AMD. The disease and loss of vision may progress despite treatment.
Laser surgery. This procedure uses a laser to destroy the fragile, leaky blood vessels. A high energy beam of light is aimed directly onto the new blood vessels and destroys them, preventing further loss of vision. However, laser treatment may also destroy some surrounding healthy tissue and some vision. Only a small percentage of people with wet AMD can be treated with laser surgery. Laser surgery is more effective if the leaky blood vessels have developed away from the fovea, the central part of the macula. (See illustration at the beginning of this document.) Laser surgery is performed in a doctor's office or eye clinic.
The risk of new blood vessels developing after laser treatment is high. Repeated treatments may be necessary. In some cases, vision loss may progress despite repeated treatments.
Photodynamic therapy. A drug called verteporfin is injected into your arm. It travels throughout the body, including the new blood vessels in your eye. The drug tends to "stick" to the surface of new blood vessels. Next, a light is shined into your eye for about 90 seconds. The light activates the drug. The activated drug destroys the new blood vessels and leads to a slower rate of vision decline. Unlike laser surgery, this drug does not destroy surrounding healthy tissue. Because the drug is activated by light, you must avoid exposing your skin or eyes to direct sunlight or bright indoor light for five days after treatment.
Photodynamic therapy is relatively painless. It takes about 20 minutes and can be performed in a doctor's office.
Photodynamic therapy slows the rate of vision loss. It does not stop vision loss or restore vision in eyes already damaged by advanced AMD. Treatment results often are temporary. You may need to be treated again.
Injections. Wet AMD can now be treated with new drugs that are injected into the eye (anti-VEGF therapy). Abnormally high levels of a specific growth factor occur in eyes with wet AMD and promote the growth of abnormal new blood vessels. This drug treatment blocks the effects of the growth factor.
You will need multiple injections that may be given as often as monthly. The eye is numbed before each injection. After the injection, you will remain in the doctor's office for a while and your eye will be monitored. This drug treatment can help slow down vision loss from AMD and in some cases improve sight.
How is dry AMD treated?
Once dry AMD reaches the advanced stage, no form of treatment can prevent vision loss. However, treatment can delay and possibly prevent intermediate AMD from progressing to the advanced stage, in which vision loss occurs.
Age-Related Eye Disease Study (AREDS)
What is the dosage of the AREDS formulation? The specific daily amounts of antioxidants and zinc used by the study researchers were 500 milligrams of vitamin C, 400 International Units of vitamin E, 15 milligrams of beta-carotene (often labeled as equivalent to 25,000 International Units of vitamin A), 80 milligrams of zinc as zinc oxide, and two milligrams of copper as cupric oxide. Copper was added to the AREDS formulation containing zinc to prevent copper deficiency anemia, a condition associated with high levels of zinc intake.Who should take the AREDS formulation?
People who are at high risk for developing advanced AMD should consider taking the formulation. You are at high risk for developing advanced AMD if you have either:
1. Intermediate AMD in one or both eyes.
OR
2. Advanced AMD (dry or wet) in one eye but not the other eye.
Your eye care professional can tell you if you have AMD, its stage, and your risk for developing the advanced form.
The AREDS formulation is not a cure for AMD. It will not restore vision already lost from the disease. However, it may delay the onset of advanced AMD. It may help people who are at high risk for developing advanced AMD keep their vision.
Can people with early stage AMD take the AREDS formulation to help prevent the disease from progressing to the intermediate stage? There is no apparent need for those diagnosed with early stage AMD to take the AREDS formulation. The study did not find that the formulation provided a benefit to those with early stage AMD. If you have early stage AMD, a comprehensive dilated eye exam every year can help determine if the disease is progressing. If early stage AMD progresses to the intermediate stage, discuss taking the formulation with your doctor.
Can diet alone provide the same high levels of antioxidants and zinc as the AREDS formulation? No. The high levels of vitamins and minerals are difficult to achieve from diet alone. However, previous studies have suggested that people who have diets rich in green leafy vegetables have a lower risk of developing AMD.
Can a daily multivitamin alone provide the same high levels of antioxidants and zinc as the AREDS formulation?No. The formulation's levels of antioxidants and zinc are considerably higher than the amounts in any daily multivitamin.
If you are already taking daily multivitamins and your doctor suggests you take the high-dose AREDS formulation, be sure to review all your vitamin supplements with your doctor before you begin. Because multivitamins contain many important vitamins not found in the AREDS formulation, you may want to take a multivitamin along with the AREDS formulation. For example, people with osteoporosis need to be particularly concerned about taking vitamin D, which is not in the AREDS formulation.
How can I take care of my vision now that I have AMD?
Dry AMD. If you have dry AMD, you should have a comprehensive dilated eye exam at least once a year. Your eye care professional can monitor your condition and check for other eye diseases. Also, if you have intermediate AMD in one or both eyes, or advanced AMD in one eye only, your doctor may suggest that you take the AREDS formulation containing the high levels of antioxidants and zinc.
Because dry AMD can turn into wet AMD at any time, you should get an Amsler grid from your eye care professional. Use the grid every day to evaluate your vision for signs of wet AMD. This quick test works best for people who still have good central vision. Check each eye separately. Cover one eye and look at the grid. Then cover your other eye and look at the grid. If you detect any changes in the appearance of this grid or in your everyday vision while reading the newspaper or watching television, get a comprehensive dilated eye exam.
Wet AMD. If you have wet AMD and your doctor advises treatment, do not wait. After laser surgery or photodynamic therapy, you will need frequent eye exams to detect any recurrence of leaking blood vessels. Studies show that people who smoke have a greater risk of recurrence than those who don't. In addition, check your vision at home with the Amsler grid. If you detect any changes, schedule an eye exam immediately.
What can I do if I have already lost some vision from AMD?
If you have lost some sight from AMD, don't be afraid to use your eyes for reading, watching TV, and other routine activities. Normal use of your eyes will not cause further damage to your vision.
If you have lost some sight from AMD, ask your eye care professional about low vision services and devices that may help you make the most of your remaining vision. Ask for a referral to a specialist in low vision. Many community organizations and agencies offer information about low vision counseling, training, and other special services for people with visual impairments. A nearby school of medicine or optometry may provide low vision services.
Age-Related Macular Degeneration (AMD) Defined What is age-related macular degeneration? Age-related macular degeneration (AMD) is a disease associated with aging that gradually destroys sharp, central vision. Central vision is needed for seeing objects clearly and for common daily tasks such as reading and driving. AMD affects the macula, the part of the eye that allows you to see fine detail. AMD causes no pain. In some cases, AMD advances so slowly that people notice little change in their vision. In others, the disease progresses faster and may lead to a loss of vision in both eyes. AMD is a leading cause of vision loss in Americans 60 years of age and older. AMD occurs in two forms: wet and dry. Where is the macula? The macula is located in the center of the retina, the light-sensitive tissue at the back of the eye. The retina instantly converts light, or an image, into electrical impulses. The retina then sends these impulses, or nerve signals, to the brain. What is wet AMD? Wet AMD occurs when abnormal blood vessels behind the retina start to grow under the macula. These new blood vessels tend to be very fragile and often leak blood and fluid. The blood and fluid raise the macula from its normal place at the back of the eye. Damage to the macula occurs rapidly. With wet AMD, loss of central vision can occur quickly. Wet AMD is also known as advanced AMD. It does not have stages like dry AMD. An early symptom of wet AMD is that straight lines appear wavy. If you notice this condition or other changes to your vision, contact your eye care professional at once. You need a comprehensive dilated eye exam. What is dry AMD? Dry AMD occurs when the light-sensitive cells in the macula slowly break down, gradually blurring central vision in the affected eye. As dry AMD gets worse, you may see a blurred spot in the center of your vision. Over time, as less of the macula functions, central vision is gradually lost in the affected eye. The most common symptom of dry AMD is slightly blurred vision. You may have difficulty recognizing faces. You may need more light for reading and other tasks. Dry AMD generally affects both eyes, but vision can be lost in one eye while the other eye seems unaffected. One of the most common early signs of dry AMD is drusen. What are drusen? Drusen are yellow deposits under the retina. They often are found in people over age 60. Your eye care professional can detect drusen during a comprehensive dilated eye exam. Drusen alone do not usually cause vision loss. In fact, scientists are unclear about the connection between drusen and AMD. They do know that an increase in the size or number of drusen raises a person's risk of developing either advanced dry AMD or wet AMD. These changes can cause serious vision loss. Dry AMD has three stages, all of which may occur in one or both eyes: Early AMD. People with early AMD have either several small drusen or a few medium-sized drusen. At this stage, there are no symptoms and no vision loss. Intermediate AMD. People with intermediate AMD have either many medium-sized drusen or one or more large drusen. Some people see a blurred spot in the center of their vision. More light may be needed for reading and other tasks. Advanced Dry AMD. In addition to drusen, people with advanced dry AMD have a breakdown of light-sensitive cells and supporting tissue in the central retinal area. This breakdown can cause a blurred spot in the center of your vision. Over time, the blurred spot may get bigger and darker, taking more of your central vision. You may have difficulty reading or recognizing faces until they are very close to you Frequently Asked Questions about wet and dry AMD Which is more common-the dry form or the wet form? The dry form is much more common. More than 85 percent of all people with intermediate and advanced AMD combined have the dry form. However, if only advanced AMD is considered, about two-thirds of patients have the wet form. Because almost all vision loss comes from advanced AMD, the wet form leads to significantly more vision loss than the dry form. Can the dry form turn into the wet form? Yes. All people who have the wet form had the dry form first. The dry form can advance and cause vision loss without turning into the wet form. The dry form also can suddenly turn into the wet form, even during early stage AMD. There is no way to tell if or when the dry form will turn into the wet form. The dry form has early and intermediate stages. Does the wet form have similar stages? No. The wet form is considered advanced AMD. Can advanced AMD be either the dry form or the wet form? Yes. Both the wet form and the advanced dry form are considered advanced AMD. Vision loss occurs with either form. In most cases, only advanced AMD can cause vision loss. People who have advanced AMD in one eye are at especially high risk of developing advanced AMD in the other eye. Causes and Risk Factors Who is at risk for AMD? The greatest risk factor is age. Although AMD may occur during middle age, studies show that people over age 60 are clearly at greater risk than other age groups. For instance, a large study found that people in middle-age have about a 2 percent risk of getting AMD, but this risk increased to nearly 30 percent in those over age 75. Other risk factors include: Smoking. Smoking may increase the risk of AMD. Obesity. Research studies suggest a link between obesity and the progression of early and intermediate stage AMD to advanced AMD. Race. Whites are much more likely to lose vision from AMD than African Americans. Family history. Those with immediate family members who have AMD are at a higher risk of developing the disease. Gender. Women appear to be at greater risk than men. Can my lifestyle make a difference? Your lifestyle can play a role in reducing your risk of developing AMD. Eat a healthy diet high in green leafy vegetables and fish. Don't smoke. Maintain normal blood pressure. Watch your weight. Exercise. Symptoms and Detection What are the symptoms? Both dry and wet AMD cause no pain. For dry AMD: the most common early sign is blurred vision. As fewer cells in the macula are able to function, people will see details less clearly in front of them, such as faces or words in a book. Often this blurred vision will go away in brighter light. If the loss of these light-sensing cells becomes great, people may see a small--but growing--blind spot in the middle of their field of vision. For wet AMD: the classic early symptom is that straight lines appear crooked. This results when fluid from the leaking blood vessels gathers and lifts the macula, distorting vision. A small blind spot may also appear in wet AMD, resulting in loss of one's central vision. How is AMD detected? Your eye care professional may suspect AMD if you are over age 60 and have had recent changes in your central vision. To look for signs of the disease, he or she will use eye drops to dilate, or enlarge, your pupils. Dilating the pupils allows your eye care professional to view the back of the eye better.
What is age-related macular degeneration?
Age-related macular degeneration (AMD) is a disease associated with aging that gradually destroys sharp, central vision. Central vision is needed for seeing objects clearly and for common daily tasks such as reading and driving.
AMD affects the macula, the part of the eye that allows you to see fine detail. AMD causes no pain.
In some cases, AMD advances so slowly that people notice little change in their vision. In others, the disease progresses faster and may lead to a loss of vision in both eyes. AMD is a leading cause of vision loss in Americans 60 years of age and older.
AMD occurs in two forms: wet and dry.
Where is the macula?
The macula is located in the center of the retina, the light-sensitive tissue at the back of the eye. The retina instantly converts light, or an image, into electrical impulses. The retina then sends these impulses, or nerve signals, to the brain.
What is wet AMD?
Wet AMD occurs when abnormal blood vessels behind the retina start to grow under the macula. These new blood vessels tend to be very fragile and often leak blood and fluid. The blood and fluid raise the macula from its normal place at the back of the eye. Damage to the macula occurs rapidly.
With wet AMD, loss of central vision can occur quickly. Wet AMD is also known as advanced AMD. It does not have stages like dry AMD.
An early symptom of wet AMD is that straight lines appear wavy. If you notice this condition or other changes to your vision, contact your eye care professional at once. You need a comprehensive dilated eye exam.
What is dry AMD?
Dry AMD occurs when the light-sensitive cells in the macula slowly break down, gradually blurring central vision in the affected eye. As dry AMD gets worse, you may see a blurred spot in the center of your vision. Over time, as less of the macula functions, central vision is gradually lost in the affected eye.
The most common symptom of dry AMD is slightly blurred vision. You may have difficulty recognizing faces. You may need more light for reading and other tasks. Dry AMD generally affects both eyes, but vision can be lost in one eye while the other eye seems unaffected.
One of the most common early signs of dry AMD is drusen.
What are drusen?
Drusen are yellow deposits under the retina. They often are found in people over age 60. Your eye care professional can detect drusen during a comprehensive dilated eye exam.
Drusen alone do not usually cause vision loss. In fact, scientists are unclear about the connection between drusen and AMD. They do know that an increase in the size or number of drusen raises a person's risk of developing either advanced dry AMD or wet AMD. These changes can cause serious vision loss.
Dry AMD has three stages, all of which may occur in one or both eyes:
Early AMD. People with early AMD have either several small drusen or a few medium-sized drusen. At this stage, there are no symptoms and no vision loss.
Intermediate AMD. People with intermediate AMD have either many medium-sized drusen or one or more large drusen. Some people see a blurred spot in the center of their vision. More light may be needed for reading and other tasks.
Advanced Dry AMD. In addition to drusen, people with advanced dry AMD have a breakdown of light-sensitive cells and supporting tissue in the central retinal area. This breakdown can cause a blurred spot in the center of your vision. Over time, the blurred spot may get bigger and darker, taking more of your central vision. You may have difficulty reading or recognizing faces until they are very close to you
Frequently Asked Questions about wet and dry AMD
Which is more common-the dry form or the wet form?
The dry form is much more common. More than 85 percent of all people with intermediate and advanced AMD combined have the dry form.
However, if only advanced AMD is considered, about two-thirds of patients have the wet form. Because almost all vision loss comes from advanced AMD, the wet form leads to significantly more vision loss than the dry form.
Can the dry form turn into the wet form?
Yes. All people who have the wet form had the dry form first.
The dry form can advance and cause vision loss without turning into the wet form. The dry form also can suddenly turn into the wet form, even during early stage AMD. There is no way to tell if or when the dry form will turn into the wet form.
The dry form has early and intermediate stages. Does the wet form have similar stages?
No. The wet form is considered advanced AMD.
Can advanced AMD be either the dry form or the wet form?
Yes. Both the wet form and the advanced dry form are considered advanced AMD. Vision loss occurs with either form. In most cases, only advanced AMD can cause vision loss.
People who have advanced AMD in one eye are at especially high risk of developing advanced AMD in the other eye.
Causes and Risk Factors
Who is at risk for AMD?
The greatest risk factor is age. Although AMD may occur during middle age, studies show that people over age 60 are clearly at greater risk than other age groups. For instance, a large study found that people in middle-age have about a 2 percent risk of getting AMD, but this risk increased to nearly 30 percent in those over age 75.
Other risk factors include:
Smoking. Smoking may increase the risk of AMD.
Obesity. Research studies suggest a link between obesity and the progression of early and intermediate stage AMD to advanced AMD.
Race. Whites are much more likely to lose vision from AMD than African Americans.
Family history. Those with immediate family members who have AMD are at a higher risk of developing the disease.
Gender. Women appear to be at greater risk than men.
Can my lifestyle make a difference?
Your lifestyle can play a role in reducing your risk of developing AMD.
Eat a healthy diet high in green leafy vegetables and fish.
Don't smoke.
Maintain normal blood pressure.
Watch your weight.
Exercise.
Symptoms and Detection
What are the symptoms?
Both dry and wet AMD cause no pain.
For dry AMD: the most common early sign is blurred vision. As fewer cells in the macula are able to function, people will see details less clearly in front of them, such as faces or words in a book. Often this blurred vision will go away in brighter light. If the loss of these light-sensing cells becomes great, people may see a small--but growing--blind spot in the middle of their field of vision.
For wet AMD: the classic early symptom is that straight lines appear crooked. This results when fluid from the leaking blood vessels gathers and lifts the macula, distorting vision. A small blind spot may also appear in wet AMD, resulting in loss of one's central vision.
How is AMD detected?
Your eye care professional may suspect AMD if you are over age 60 and have had recent changes in your central vision. To look for signs of the disease, he or she will use eye drops to dilate, or enlarge, your pupils. Dilating the pupils allows your eye care professional to view the back of the eye better.
AMD is detected during a comprehensive eye exam that includes:
Visual acuity test. This eye chart test measures how well you see at various distances.
Dilated eye exam. Drops are placed in your eyes to widen, or dilate, the pupils. Your eye care professional uses a special magnifying lens to examine your retina and optic nerve for signs of AMD and other eye problems. After the exam, your close-up vision may remain blurred for several hours.
Tonometry. An instrument measures the pressure inside the eye. Numbing drops may be applied to your eye for this test.
Treatment
How is wet AMD treated?
Wet AMD can be treated with laser surgery, photodynamic therapy, and injections into the eye. None of these treatments is a cure for wet AMD. The disease and loss of vision may progress despite treatment.
Laser surgery. This procedure uses a laser to destroy the fragile, leaky blood vessels. A high energy beam of light is aimed directly onto the new blood vessels and destroys them, preventing further loss of vision. However, laser treatment may also destroy some surrounding healthy tissue and some vision. Only a small percentage of people with wet AMD can be treated with laser surgery. Laser surgery is more effective if the leaky blood vessels have developed away from the fovea, the central part of the macula. (See illustration at the beginning of this document.) Laser surgery is performed in a doctor's office or eye clinic.
The risk of new blood vessels developing after laser treatment is high. Repeated treatments may be necessary. In some cases, vision loss may progress despite repeated treatments.
Photodynamic therapy. A drug called verteporfin is injected into your arm. It travels throughout the body, including the new blood vessels in your eye. The drug tends to "stick" to the surface of new blood vessels. Next, a light is shined into your eye for about 90 seconds. The light activates the drug. The activated drug destroys the new blood vessels and leads to a slower rate of vision decline. Unlike laser surgery, this drug does not destroy surrounding healthy tissue. Because the drug is activated by light, you must avoid exposing your skin or eyes to direct sunlight or bright indoor light for five days after treatment.
Photodynamic therapy is relatively painless. It takes about 20 minutes and can be performed in a doctor's office.
Photodynamic therapy slows the rate of vision loss. It does not stop vision loss or restore vision in eyes already damaged by advanced AMD. Treatment results often are temporary. You may need to be treated again.
Injections. Wet AMD can now be treated with new drugs that are injected into the eye (anti-VEGF therapy). Abnormally high levels of a specific growth factor occur in eyes with wet AMD and promote the growth of abnormal new blood vessels. This drug treatment blocks the effects of the growth factor.
You will need multiple injections that may be given as often as monthly. The eye is numbed before each injection. After the injection, you will remain in the doctor's office for a while and your eye will be monitored. This drug treatment can help slow down vision loss from AMD and in some cases improve sight.
How is dry AMD treated?
Once dry AMD reaches the advanced stage, no form of treatment can prevent vision loss. However, treatment can delay and possibly prevent intermediate AMD from progressing to the advanced stage, in which vision loss occurs.
Age-Related Eye Disease Study (AREDS)
What is the dosage of the AREDS formulation? The specific daily amounts of antioxidants and zinc used by the study researchers were 500 milligrams of vitamin C, 400 International Units of vitamin E, 15 milligrams of beta-carotene (often labeled as equivalent to 25,000 International Units of vitamin A), 80 milligrams of zinc as zinc oxide, and two milligrams of copper as cupric oxide. Copper was added to the AREDS formulation containing zinc to prevent copper deficiency anemia, a condition associated with high levels of zinc intake.Who should take the AREDS formulation?
People who are at high risk for developing advanced AMD should consider taking the formulation. You are at high risk for developing advanced AMD if you have either:
1. Intermediate AMD in one or both eyes.
OR
2. Advanced AMD (dry or wet) in one eye but not the other eye.
Your eye care professional can tell you if you have AMD, its stage, and your risk for developing the advanced form.
The AREDS formulation is not a cure for AMD. It will not restore vision already lost from the disease. However, it may delay the onset of advanced AMD. It may help people who are at high risk for developing advanced AMD keep their vision.
Can people with early stage AMD take the AREDS formulation to help prevent the disease from progressing to the intermediate stage? There is no apparent need for those diagnosed with early stage AMD to take the AREDS formulation. The study did not find that the formulation provided a benefit to those with early stage AMD. If you have early stage AMD, a comprehensive dilated eye exam every year can help determine if the disease is progressing. If early stage AMD progresses to the intermediate stage, discuss taking the formulation with your doctor.
Can diet alone provide the same high levels of antioxidants and zinc as the AREDS formulation? No. The high levels of vitamins and minerals are difficult to achieve from diet alone. However, previous studies have suggested that people who have diets rich in green leafy vegetables have a lower risk of developing AMD.
Can a daily multivitamin alone provide the same high levels of antioxidants and zinc as the AREDS formulation?No. The formulation's levels of antioxidants and zinc are considerably higher than the amounts in any daily multivitamin.
If you are already taking daily multivitamins and your doctor suggests you take the high-dose AREDS formulation, be sure to review all your vitamin supplements with your doctor before you begin. Because multivitamins contain many important vitamins not found in the AREDS formulation, you may want to take a multivitamin along with the AREDS formulation. For example, people with osteoporosis need to be particularly concerned about taking vitamin D, which is not in the AREDS formulation.
How can I take care of my vision now that I have AMD?
Dry AMD. If you have dry AMD, you should have a comprehensive dilated eye exam at least once a year. Your eye care professional can monitor your condition and check for other eye diseases. Also, if you have intermediate AMD in one or both eyes, or advanced AMD in one eye only, your doctor may suggest that you take the AREDS formulation containing the high levels of antioxidants and zinc.
Because dry AMD can turn into wet AMD at any time, you should get an Amsler grid from your eye care professional. Use the grid every day to evaluate your vision for signs of wet AMD. This quick test works best for people who still have good central vision. Check each eye separately. Cover one eye and look at the grid. Then cover your other eye and look at the grid. If you detect any changes in the appearance of this grid or in your everyday vision while reading the newspaper or watching television, get a comprehensive dilated eye exam.
Wet AMD. If you have wet AMD and your doctor advises treatment, do not wait. After laser surgery or photodynamic therapy, you will need frequent eye exams to detect any recurrence of leaking blood vessels. Studies show that people who smoke have a greater risk of recurrence than those who don't. In addition, check your vision at home with the Amsler grid. If you detect any changes, schedule an eye exam immediately.
What can I do if I have already lost some vision from AMD?
If you have lost some sight from AMD, don't be afraid to use your eyes for reading, watching TV, and other routine activities. Normal use of your eyes will not cause further damage to your vision.
If you have lost some sight from AMD, ask your eye care professional about low vision services and devices that may help you make the most of your remaining vision. Ask for a referral to a specialist in low vision. Many community organizations and agencies offer information about low vision counseling, training, and other special services for people with visual impairments. A nearby school of medicine or optometry may provide low vision services.
Age-Related Macular Degeneration (AMD) Defined What is age-related macular degeneration? Age-related macular degeneration (AMD) is a disease associated with aging that gradually destroys sharp, central vision. Central vision is needed for seeing objects clearly and for common daily tasks such as reading and driving. AMD affects the macula, the part of the eye that allows you to see fine detail. AMD causes no pain. In some cases, AMD advances so slowly that people notice little change in their vision. In others, the disease progresses faster and may lead to a loss of vision in both eyes. AMD is a leading cause of vision loss in Americans 60 years of age and older. AMD occurs in two forms: wet and dry. Where is the macula? The macula is located in the center of the retina, the light-sensitive tissue at the back of the eye. The retina instantly converts light, or an image, into electrical impulses. The retina then sends these impulses, or nerve signals, to the brain. What is wet AMD? Wet AMD occurs when abnormal blood vessels behind the retina start to grow under the macula. These new blood vessels tend to be very fragile and often leak blood and fluid. The blood and fluid raise the macula from its normal place at the back of the eye. Damage to the macula occurs rapidly. With wet AMD, loss of central vision can occur quickly. Wet AMD is also known as advanced AMD. It does not have stages like dry AMD. An early symptom of wet AMD is that straight lines appear wavy. If you notice this condition or other changes to your vision, contact your eye care professional at once. You need a comprehensive dilated eye exam. What is dry AMD? Dry AMD occurs when the light-sensitive cells in the macula slowly break down, gradually blurring central vision in the affected eye. As dry AMD gets worse, you may see a blurred spot in the center of your vision. Over time, as less of the macula functions, central vision is gradually lost in the affected eye. The most common symptom of dry AMD is slightly blurred vision. You may have difficulty recognizing faces. You may need more light for reading and other tasks. Dry AMD generally affects both eyes, but vision can be lost in one eye while the other eye seems unaffected. One of the most common early signs of dry AMD is drusen. What are drusen? Drusen are yellow deposits under the retina. They often are found in people over age 60. Your eye care professional can detect drusen during a comprehensive dilated eye exam. Drusen alone do not usually cause vision loss. In fact, scientists are unclear about the connection between drusen and AMD. They do know that an increase in the size or number of drusen raises a person's risk of developing either advanced dry AMD or wet AMD. These changes can cause serious vision loss. Dry AMD has three stages, all of which may occur in one or both eyes: Early AMD. People with early AMD have either several small drusen or a few medium-sized drusen. At this stage, there are no symptoms and no vision loss. Intermediate AMD. People with intermediate AMD have either many medium-sized drusen or one or more large drusen. Some people see a blurred spot in the center of their vision. More light may be needed for reading and other tasks. Advanced Dry AMD. In addition to drusen, people with advanced dry AMD have a breakdown of light-sensitive cells and supporting tissue in the central retinal area. This breakdown can cause a blurred spot in the center of your vision. Over time, the blurred spot may get bigger and darker, taking more of your central vision. You may have difficulty reading or recognizing faces until they are very close to you Frequently Asked Questions about wet and dry AMD Which is more common-the dry form or the wet form? The dry form is much more common. More than 85 percent of all people with intermediate and advanced AMD combined have the dry form. However, if only advanced AMD is considered, about two-thirds of patients have the wet form. Because almost all vision loss comes from advanced AMD, the wet form leads to significantly more vision loss than the dry form. Can the dry form turn into the wet form? Yes. All people who have the wet form had the dry form first. The dry form can advance and cause vision loss without turning into the wet form. The dry form also can suddenly turn into the wet form, even during early stage AMD. There is no way to tell if or when the dry form will turn into the wet form. The dry form has early and intermediate stages. Does the wet form have similar stages? No. The wet form is considered advanced AMD. Can advanced AMD be either the dry form or the wet form? Yes. Both the wet form and the advanced dry form are considered advanced AMD. Vision loss occurs with either form. In most cases, only advanced AMD can cause vision loss. People who have advanced AMD in one eye are at especially high risk of developing advanced AMD in the other eye. Causes and Risk Factors Who is at risk for AMD? The greatest risk factor is age. Although AMD may occur during middle age, studies show that people over age 60 are clearly at greater risk than other age groups. For instance, a large study found that people in middle-age have about a 2 percent risk of getting AMD, but this risk increased to nearly 30 percent in those over age 75. Other risk factors include: Smoking. Smoking may increase the risk of AMD. Obesity. Research studies suggest a link between obesity and the progression of early and intermediate stage AMD to advanced AMD. Race. Whites are much more likely to lose vision from AMD than African Americans. Family history. Those with immediate family members who have AMD are at a higher risk of developing the disease. Gender. Women appear to be at greater risk than men. Can my lifestyle make a difference? Your lifestyle can play a role in reducing your risk of developing AMD. Eat a healthy diet high in green leafy vegetables and fish. Don't smoke. Maintain normal blood pressure. Watch your weight. Exercise. Symptoms and Detection What are the symptoms? Both dry and wet AMD cause no pain. For dry AMD: the most common early sign is blurred vision. As fewer cells in the macula are able to function, people will see details less clearly in front of them, such as faces or words in a book. Often this blurred vision will go away in brighter light. If the loss of these light-sensing cells becomes great, people may see a small--but growing--blind spot in the middle of their field of vision. For wet AMD: the classic early symptom is that straight lines appear crooked. This results when fluid from the leaking blood vessels gathers and lifts the macula, distorting vision. A small blind spot may also appear in wet AMD, resulting in loss of one's central vision. How is AMD detected? Your eye care professional may suspect AMD if you are over age 60 and have had recent changes in your central vision. To look for signs of the disease, he or she will use eye drops to dilate, or enlarge, your pupils. Dilating the pupils allows your eye care professional to view the back of the eye better.
amblyopia
What is amblyopia?
The brain and the eye work together to produce vision. Light enters the eye and is changed into nerve signals that travel along the optic nerve to the brain. Amblyopia is the medical term used when the vision in one of the eyes is reduced because the eye and the brain are not working together properly. The eye itself looks normal, but it is not being used normally because the brain is favoring the other eye. This condition is also sometimes called lazy eye.
How common is amblyopia?
Amblyopia is the most common cause of visual impairment in childhood. The condition affects approximately 2 to 3 out of every 100 children. Unless it is successfully treated in early childhood, amblyopia usually persists into adulthood, and is the most common cause of monocular (one eye) visual impairment among children and young and middle-aged adults.
What causes amblyopia?
Amblyopia may be caused by any condition that affects normal visual development or use of the eyes. Amblyopia can be caused by strabismus, an imbalance in the positioning of the two eyes. Strabismus can cause the eyes to cross in (esotropia) or turn out (exotropia). Sometimes amblyopia is caused when one eye is more nearsighted, farsighted, or astigmatic than the other eye. Occasionally, amblyopia is caused by other eye conditions such as cataract.
How is amblyopia treated in children?
Treating amblyopia involves making the child use the eye with the reduced vision (weaker eye). Currently, there are two ways used to do this:
AtropineA drop of a drug called atropine is placed in the stronger eye once a day to temporarily blur the vision so that the child will prefer to use the eye with amblyopia. Treatment with atropine also stimulates vision in the weaker eye and helps the part of the brain that manages vision develop more completely.
PatchingAn opaque, adhesive patch is worn over the stronger eye for weeks to months. This therapy forces the child to use the eye with amblyopia. Patching stimulates vision in the weaker eye and helps the part of the brain that manages vision develop more completely.
Previously, eye care professionals often thought that treating amblyopia in older children would be of little benefit. However, surprising results from a nationwide clinical trial show that many children age seven through 17 with amblyopia may benefit from treatments that are more commonly used on younger children. This study shows that age alone should not be used as a factor to decide whether or not to treat a child for amblyopia.
Can amblyopia be treated in adults?
Studies are very limited at this time and scientists don’t know what the success rate might be for treating amblyopia in adults. During the first six to nine years of life, the visual system develops very rapidly. Complicated connections between the eye and the brain are created during that period of growth and development. Scientists are exploring whether treatment for amblyopia in adults can improve vision.
What is amblyopia? The brain and the eye work together to produce vision. Light enters the eye and is changed into nerve signals that travel along the optic nerve to the brain. Amblyopia is the medical term used when the vision in one of the eyes is reduced because the eye and the brain are not working together properly. The eye itself looks normal, but it is not being used normally because the brain is favoring the other eye. This condition is also sometimes called lazy eye. How common is amblyopia? Amblyopia is the most common cause of visual impairment in childhood. The condition affects approximately 2 to 3 out of every 100 children. Unless it is successfully treated in early childhood, amblyopia usually persists into adulthood, and is the most common cause of monocular (one eye) visual impairment among children and young and middle-aged adults. What causes amblyopia? Amblyopia may be caused by any condition that affects normal visual development or use of the eyes. Amblyopia can be caused by strabismus, an imbalance in the positioning of the two eyes. Strabismus can cause the eyes to cross in (esotropia) or turn out (exotropia). Sometimes amblyopia is caused when one eye is more nearsighted, farsighted, or astigmatic than the other eye. Occasionally, amblyopia is caused by other eye conditions such as cataract. How is amblyopia treated in children? Treating amblyopia involves making the child use the eye with the reduced vision (weaker eye). Currently, there are two ways used to do this: AtropineA drop of a drug called atropine is placed in the stronger eye once a day to temporarily blur the vision so that the child will prefer to use the eye with amblyopia. Treatment with atropine also stimulates vision in the weaker eye and helps the part of the brain that manages vision develop more completely. PatchingAn opaque, adhesive patch is worn over the stronger eye for weeks to months. This therapy forces the child to use the eye with amblyopia. Patching stimulates vision in the weaker eye and helps the part of the brain that manages vision develop more completely. Previously, eye care professionals often thought that treating amblyopia in older children would be of little benefit. However, surprising results from a nationwide clinical trial show that many children age seven through 17 with amblyopia may benefit from treatments that are more commonly used on younger children. This study shows that age alone should not be used as a factor to decide whether or not to treat a child for amblyopia. Can amblyopia be treated in adults? Studies are very limited at this time and scientists don’t know what the success rate might be for treating amblyopia in adults. During the first six to nine years of life, the visual system develops very rapidly. Complicated connections between the eye and the brain are created during that period of growth and development. Scientists are exploring whether treatment for amblyopia in adults can improve vision.
The brain and the eye work together to produce vision. Light enters the eye and is changed into nerve signals that travel along the optic nerve to the brain. Amblyopia is the medical term used when the vision in one of the eyes is reduced because the eye and the brain are not working together properly. The eye itself looks normal, but it is not being used normally because the brain is favoring the other eye. This condition is also sometimes called lazy eye.
How common is amblyopia?
Amblyopia is the most common cause of visual impairment in childhood. The condition affects approximately 2 to 3 out of every 100 children. Unless it is successfully treated in early childhood, amblyopia usually persists into adulthood, and is the most common cause of monocular (one eye) visual impairment among children and young and middle-aged adults.
What causes amblyopia?
Amblyopia may be caused by any condition that affects normal visual development or use of the eyes. Amblyopia can be caused by strabismus, an imbalance in the positioning of the two eyes. Strabismus can cause the eyes to cross in (esotropia) or turn out (exotropia). Sometimes amblyopia is caused when one eye is more nearsighted, farsighted, or astigmatic than the other eye. Occasionally, amblyopia is caused by other eye conditions such as cataract.
How is amblyopia treated in children?
Treating amblyopia involves making the child use the eye with the reduced vision (weaker eye). Currently, there are two ways used to do this:
AtropineA drop of a drug called atropine is placed in the stronger eye once a day to temporarily blur the vision so that the child will prefer to use the eye with amblyopia. Treatment with atropine also stimulates vision in the weaker eye and helps the part of the brain that manages vision develop more completely.
PatchingAn opaque, adhesive patch is worn over the stronger eye for weeks to months. This therapy forces the child to use the eye with amblyopia. Patching stimulates vision in the weaker eye and helps the part of the brain that manages vision develop more completely.
Previously, eye care professionals often thought that treating amblyopia in older children would be of little benefit. However, surprising results from a nationwide clinical trial show that many children age seven through 17 with amblyopia may benefit from treatments that are more commonly used on younger children. This study shows that age alone should not be used as a factor to decide whether or not to treat a child for amblyopia.
Can amblyopia be treated in adults?
Studies are very limited at this time and scientists don’t know what the success rate might be for treating amblyopia in adults. During the first six to nine years of life, the visual system develops very rapidly. Complicated connections between the eye and the brain are created during that period of growth and development. Scientists are exploring whether treatment for amblyopia in adults can improve vision.
What is amblyopia? The brain and the eye work together to produce vision. Light enters the eye and is changed into nerve signals that travel along the optic nerve to the brain. Amblyopia is the medical term used when the vision in one of the eyes is reduced because the eye and the brain are not working together properly. The eye itself looks normal, but it is not being used normally because the brain is favoring the other eye. This condition is also sometimes called lazy eye. How common is amblyopia? Amblyopia is the most common cause of visual impairment in childhood. The condition affects approximately 2 to 3 out of every 100 children. Unless it is successfully treated in early childhood, amblyopia usually persists into adulthood, and is the most common cause of monocular (one eye) visual impairment among children and young and middle-aged adults. What causes amblyopia? Amblyopia may be caused by any condition that affects normal visual development or use of the eyes. Amblyopia can be caused by strabismus, an imbalance in the positioning of the two eyes. Strabismus can cause the eyes to cross in (esotropia) or turn out (exotropia). Sometimes amblyopia is caused when one eye is more nearsighted, farsighted, or astigmatic than the other eye. Occasionally, amblyopia is caused by other eye conditions such as cataract. How is amblyopia treated in children? Treating amblyopia involves making the child use the eye with the reduced vision (weaker eye). Currently, there are two ways used to do this: AtropineA drop of a drug called atropine is placed in the stronger eye once a day to temporarily blur the vision so that the child will prefer to use the eye with amblyopia. Treatment with atropine also stimulates vision in the weaker eye and helps the part of the brain that manages vision develop more completely. PatchingAn opaque, adhesive patch is worn over the stronger eye for weeks to months. This therapy forces the child to use the eye with amblyopia. Patching stimulates vision in the weaker eye and helps the part of the brain that manages vision develop more completely. Previously, eye care professionals often thought that treating amblyopia in older children would be of little benefit. However, surprising results from a nationwide clinical trial show that many children age seven through 17 with amblyopia may benefit from treatments that are more commonly used on younger children. This study shows that age alone should not be used as a factor to decide whether or not to treat a child for amblyopia. Can amblyopia be treated in adults? Studies are very limited at this time and scientists don’t know what the success rate might be for treating amblyopia in adults. During the first six to nine years of life, the visual system develops very rapidly. Complicated connections between the eye and the brain are created during that period of growth and development. Scientists are exploring whether treatment for amblyopia in adults can improve vision.
anophthalmia,microphthalmia
What are anophthalmia and microphthalmia?
Anophthalmia and microphthalmia are often used interchangeably. Microphthalmia is a disorder in which one or both eyes are abnormally small, while anophthalmia is the absence of one or both eyes. These rare disorders develop during pregnancy and can be associated with other birth defects.
What causes anophthalmia and microphthalmia?
Causes of these conditions may include genetic mutations and abnormal chromosomes. Researchers also believe that environmental factors, such as exposure to X-rays, chemicals, drugs, pesticides, toxins, radiation, or viruses, increase the risk of anophthalmia and microphthalmia, but research is not conclusive. Sometimes the cause in an individual patient cannot be determined.
Can anophthalmia and microphthalmia be treated?
There is no treatment for severe anophthalmia or microphthalmia that will create a new eye or restore vision. However, some less severe forms of microphthalmia may benefit from medical or surgical treatments. In almost all cases improvements to a child's appearance are possible. Children can be fitted for a prosthetic (artificial) eye for cosmetic purposes and to promote socket growth. A newborn with anophthalmia or microphthalmia will need to visit several eye care professionals, including those who specialize in pediatrics, vitreoretinal disease, orbital and oculoplastic surgery, ophthalmic genetics, and prosthetic devices for the eye. Each specialist can provide information and possible treatments resulting in the best care for the child and family. The specialist in prosthetic diseases for the eye will make conformers, plastic structures that help support the face and encourage the eye socket to grow. As the face develops, new conformers will need to be made. A child with anophthalmia may also need to use expanders in addition to conformers to further enlarge the eye socket. Once the face is fully developed, prosthetic eyes can be made and placed. Prosthetic eyes will not restore vision.
How do conformers and prosthetic eyes look?
A painted prosthesis that looks like a normal eye is usually fitted between ages one and two. Until then, clear conformers are used. When the conformers are in place the eye socket will look black. These conformers are not painted to look like a normal eye because they are changed too frequently. Every few weeks a child will progress to a larger size conformer until about two years of age. If a child needs to wear conformers after age two, the conformers will be painted like a regular prosthesis, giving the appearance of a normal but smaller eye. The average child will need three to four new painted prostheses before the age of 10.
How is microphthalmia managed if there is residual vision in the eye?
Children with microphthalmia may have some residual vision (limited sight). In these cases, the good eye can be patched to strengthen vision in the microphthalmic eye. A prosthesis can be made to cap the microphthalmic eye to help with cosmetic appearance, while preserving the remaining sight.
What are anophthalmia and microphthalmia? Anophthalmia and microphthalmia are often used interchangeably. Microphthalmia is a disorder in which one or both eyes are abnormally small, while anophthalmia is the absence of one or both eyes. These rare disorders develop during pregnancy and can be associated with other birth defects. What causes anophthalmia and microphthalmia? Causes of these conditions may include genetic mutations and abnormal chromosomes. Researchers also believe that environmental factors, such as exposure to X-rays, chemicals, drugs, pesticides, toxins, radiation, or viruses, increase the risk of anophthalmia and microphthalmia, but research is not conclusive. Sometimes the cause in an individual patient cannot be determined. Can anophthalmia and microphthalmia be treated? There is no treatment for severe anophthalmia or microphthalmia that will create a new eye or restore vision. However, some less severe forms of microphthalmia may benefit from medical or surgical treatments. In almost all cases improvements to a child's appearance are possible. Children can be fitted for a prosthetic (artificial) eye for cosmetic purposes and to promote socket growth. A newborn with anophthalmia or microphthalmia will need to visit several eye care professionals, including those who specialize in pediatrics, vitreoretinal disease, orbital and oculoplastic surgery, ophthalmic genetics, and prosthetic devices for the eye. Each specialist can provide information and possible treatments resulting in the best care for the child and family. The specialist in prosthetic diseases for the eye will make conformers, plastic structures that help support the face and encourage the eye socket to grow. As the face develops, new conformers will need to be made. A child with anophthalmia may also need to use expanders in addition to conformers to further enlarge the eye socket. Once the face is fully developed, prosthetic eyes can be made and placed. Prosthetic eyes will not restore vision.
Anophthalmia and microphthalmia are often used interchangeably. Microphthalmia is a disorder in which one or both eyes are abnormally small, while anophthalmia is the absence of one or both eyes. These rare disorders develop during pregnancy and can be associated with other birth defects.
What causes anophthalmia and microphthalmia?
Causes of these conditions may include genetic mutations and abnormal chromosomes. Researchers also believe that environmental factors, such as exposure to X-rays, chemicals, drugs, pesticides, toxins, radiation, or viruses, increase the risk of anophthalmia and microphthalmia, but research is not conclusive. Sometimes the cause in an individual patient cannot be determined.
Can anophthalmia and microphthalmia be treated?
There is no treatment for severe anophthalmia or microphthalmia that will create a new eye or restore vision. However, some less severe forms of microphthalmia may benefit from medical or surgical treatments. In almost all cases improvements to a child's appearance are possible. Children can be fitted for a prosthetic (artificial) eye for cosmetic purposes and to promote socket growth. A newborn with anophthalmia or microphthalmia will need to visit several eye care professionals, including those who specialize in pediatrics, vitreoretinal disease, orbital and oculoplastic surgery, ophthalmic genetics, and prosthetic devices for the eye. Each specialist can provide information and possible treatments resulting in the best care for the child and family. The specialist in prosthetic diseases for the eye will make conformers, plastic structures that help support the face and encourage the eye socket to grow. As the face develops, new conformers will need to be made. A child with anophthalmia may also need to use expanders in addition to conformers to further enlarge the eye socket. Once the face is fully developed, prosthetic eyes can be made and placed. Prosthetic eyes will not restore vision.
How do conformers and prosthetic eyes look?
A painted prosthesis that looks like a normal eye is usually fitted between ages one and two. Until then, clear conformers are used. When the conformers are in place the eye socket will look black. These conformers are not painted to look like a normal eye because they are changed too frequently. Every few weeks a child will progress to a larger size conformer until about two years of age. If a child needs to wear conformers after age two, the conformers will be painted like a regular prosthesis, giving the appearance of a normal but smaller eye. The average child will need three to four new painted prostheses before the age of 10.
How is microphthalmia managed if there is residual vision in the eye?
Children with microphthalmia may have some residual vision (limited sight). In these cases, the good eye can be patched to strengthen vision in the microphthalmic eye. A prosthesis can be made to cap the microphthalmic eye to help with cosmetic appearance, while preserving the remaining sight.
What are anophthalmia and microphthalmia? Anophthalmia and microphthalmia are often used interchangeably. Microphthalmia is a disorder in which one or both eyes are abnormally small, while anophthalmia is the absence of one or both eyes. These rare disorders develop during pregnancy and can be associated with other birth defects. What causes anophthalmia and microphthalmia? Causes of these conditions may include genetic mutations and abnormal chromosomes. Researchers also believe that environmental factors, such as exposure to X-rays, chemicals, drugs, pesticides, toxins, radiation, or viruses, increase the risk of anophthalmia and microphthalmia, but research is not conclusive. Sometimes the cause in an individual patient cannot be determined. Can anophthalmia and microphthalmia be treated? There is no treatment for severe anophthalmia or microphthalmia that will create a new eye or restore vision. However, some less severe forms of microphthalmia may benefit from medical or surgical treatments. In almost all cases improvements to a child's appearance are possible. Children can be fitted for a prosthetic (artificial) eye for cosmetic purposes and to promote socket growth. A newborn with anophthalmia or microphthalmia will need to visit several eye care professionals, including those who specialize in pediatrics, vitreoretinal disease, orbital and oculoplastic surgery, ophthalmic genetics, and prosthetic devices for the eye. Each specialist can provide information and possible treatments resulting in the best care for the child and family. The specialist in prosthetic diseases for the eye will make conformers, plastic structures that help support the face and encourage the eye socket to grow. As the face develops, new conformers will need to be made. A child with anophthalmia may also need to use expanders in addition to conformers to further enlarge the eye socket. Once the face is fully developed, prosthetic eyes can be made and placed. Prosthetic eyes will not restore vision.
Adamantiades,behcets disease
What is Behçet's disease?
Behçet's disease is an autoimmune disease that results from damage to blood vessels throughout the body, particularly veins. In an autoimmune disease, the immune system attacks and harms the body's own tissues.
What causes Behçet's disease?
The exact cause is unknown. It is believed that an autoimmune reaction may cause blood vessels to become inflamed, but it is not clear what triggers this reaction.
What are the symptoms of Behçet's disease?
Behçet's disease affects each person differently. The four most common symptoms are mouth sores, genital sores, inflammation inside of the eye, and skin problems. Inflammation inside of the eye (uveitis, retinitis, and iritis) occurs in more that half of those with Behçet's disease and can cause blurred vision, pain, and redness.
Other symptoms may include arthritis, blood clots, and inflammation in the central nervous system and digestive organs.
How is Behçet's disease treated?
There is no cure for Behçet's disease. Treatment typically focuses on reducing discomfort and preventing serious complications. Corticosteroids and other medications that suppress the immune system may be prescribed to treat inflammation.
What is the prognosis for someone with Behçet's disease?
Behçet's is a chronic disease that recurs. However, patients may have periods of time when symptoms go away temporarily (remission). How severe the disease is varies from patient to patient. Some patients may live normal lives, but others may become blind or severely disabled
What is Behçet's disease? Behçet's disease is an autoimmune disease that results from damage to blood vessels throughout the body, particularly veins. In an autoimmune disease, the immune system attacks and harms the body's own tissues. What causes Behçet's disease? The exact cause is unknown. It is believed that an autoimmune reaction may cause blood vessels to become inflamed, but it is not clear what triggers this reaction. What are the symptoms of Behçet's disease? Behçet's disease affects each person differently. The four most common symptoms are mouth sores, genital sores, inflammation inside of the eye, and skin problems. Inflammation inside of the eye (uveitis, retinitis, and iritis) occurs in more that half of those with Behçet's disease and can cause blurred vision, pain, and redness. Other symptoms may include arthritis, blood clots, and inflammation in the central nervous system and digestive organs. How is Behçet's disease treated? There is no cure for Behçet's disease
Behçet's disease is an autoimmune disease that results from damage to blood vessels throughout the body, particularly veins. In an autoimmune disease, the immune system attacks and harms the body's own tissues.
What causes Behçet's disease?
The exact cause is unknown. It is believed that an autoimmune reaction may cause blood vessels to become inflamed, but it is not clear what triggers this reaction.
What are the symptoms of Behçet's disease?
Behçet's disease affects each person differently. The four most common symptoms are mouth sores, genital sores, inflammation inside of the eye, and skin problems. Inflammation inside of the eye (uveitis, retinitis, and iritis) occurs in more that half of those with Behçet's disease and can cause blurred vision, pain, and redness.
Other symptoms may include arthritis, blood clots, and inflammation in the central nervous system and digestive organs.
How is Behçet's disease treated?
There is no cure for Behçet's disease. Treatment typically focuses on reducing discomfort and preventing serious complications. Corticosteroids and other medications that suppress the immune system may be prescribed to treat inflammation.
What is the prognosis for someone with Behçet's disease?
Behçet's is a chronic disease that recurs. However, patients may have periods of time when symptoms go away temporarily (remission). How severe the disease is varies from patient to patient. Some patients may live normal lives, but others may become blind or severely disabled
What is Behçet's disease? Behçet's disease is an autoimmune disease that results from damage to blood vessels throughout the body, particularly veins. In an autoimmune disease, the immune system attacks and harms the body's own tissues. What causes Behçet's disease? The exact cause is unknown. It is believed that an autoimmune reaction may cause blood vessels to become inflamed, but it is not clear what triggers this reaction. What are the symptoms of Behçet's disease? Behçet's disease affects each person differently. The four most common symptoms are mouth sores, genital sores, inflammation inside of the eye, and skin problems. Inflammation inside of the eye (uveitis, retinitis, and iritis) occurs in more that half of those with Behçet's disease and can cause blurred vision, pain, and redness. Other symptoms may include arthritis, blood clots, and inflammation in the central nervous system and digestive organs. How is Behçet's disease treated? There is no cure for Behçet's disease
Bietti's crystalline corneoretinal dystrophy
What is Bietti's Crystalline Dystrophy?
Bietti's crystalline dystrophy (BCD) is an inherited eye disease named for Dr. G. B. Bietti, an Italian ophthalmologist, who described three patients with similar symptoms in 1937. The symptoms of BCD include: crystals in the cornea (the clear covering of the eye); yellow, shiny deposits on the retina; and progressive atrophy of the retina, choriocapillaries and choroid (the back layers of the eye). This tends to lead to progressive night blindness and visual field constriction. BCD is a rare disease and appears to be more common in people with Asian ancestry.
People with BCD have crystals in some of their white blood cells (lymphocytes) that can be seen by using an electron microscope. Researchers have been unable to determine exactly what substance makes up these crystalline deposits. Their presence does not appear to harm the patient in any other way except to affect vision.
What causes Bietti's Crystalline Dystrophy?
From family studies, we know that BCD is inherited primarily in an autosomal recessive fashion. This means that an affected person receives one nonworking gene from each of his or her parents. A person who inherits a nonworking gene from only one parent will be a carrier, but will not develop the disease. A person with BCD syndrome will pass on one gene to each of his or her children. However, unless the person has children with another carrier of BCD genes, the individual's children are not at risk for developing the disease
What is Bietti's Crystalline Dystrophy? Bietti's crystalline dystrophy (BCD) is an inherited eye disease named for Dr. G. B. Bietti, an Italian ophthalmologist, who described three patients with similar symptoms in 1937. The symptoms of BCD include: crystals in the cornea (the clear covering of the eye); yellow, shiny deposits on the retina; and progressive atrophy of the retina, choriocapillaries and choroid (the back layers of the eye). This tends to lead to progressive night blindness and visual field constriction. BCD is a rare disease and appears to be more common in people with Asian ancestry. People with BCD have crystals in some of their white blood cells (lymphocytes) that can be seen by using an electron microscope. Researchers have been unable to determine exactly what substance makes up these crystalline deposits. Their presence does not appear to harm the patient in any other way except to affect vision.
Bietti's crystalline dystrophy (BCD) is an inherited eye disease named for Dr. G. B. Bietti, an Italian ophthalmologist, who described three patients with similar symptoms in 1937. The symptoms of BCD include: crystals in the cornea (the clear covering of the eye); yellow, shiny deposits on the retina; and progressive atrophy of the retina, choriocapillaries and choroid (the back layers of the eye). This tends to lead to progressive night blindness and visual field constriction. BCD is a rare disease and appears to be more common in people with Asian ancestry.
People with BCD have crystals in some of their white blood cells (lymphocytes) that can be seen by using an electron microscope. Researchers have been unable to determine exactly what substance makes up these crystalline deposits. Their presence does not appear to harm the patient in any other way except to affect vision.
What causes Bietti's Crystalline Dystrophy?
From family studies, we know that BCD is inherited primarily in an autosomal recessive fashion. This means that an affected person receives one nonworking gene from each of his or her parents. A person who inherits a nonworking gene from only one parent will be a carrier, but will not develop the disease. A person with BCD syndrome will pass on one gene to each of his or her children. However, unless the person has children with another carrier of BCD genes, the individual's children are not at risk for developing the disease
What is Bietti's Crystalline Dystrophy? Bietti's crystalline dystrophy (BCD) is an inherited eye disease named for Dr. G. B. Bietti, an Italian ophthalmologist, who described three patients with similar symptoms in 1937. The symptoms of BCD include: crystals in the cornea (the clear covering of the eye); yellow, shiny deposits on the retina; and progressive atrophy of the retina, choriocapillaries and choroid (the back layers of the eye). This tends to lead to progressive night blindness and visual field constriction. BCD is a rare disease and appears to be more common in people with Asian ancestry. People with BCD have crystals in some of their white blood cells (lymphocytes) that can be seen by using an electron microscope. Researchers have been unable to determine exactly what substance makes up these crystalline deposits. Their presence does not appear to harm the patient in any other way except to affect vision.
Granulated eyelids,blepharitis
What is blepharitis?
Blepharitis is a common condition that causes inflammation of the eyelids. The condition can be difficult to manage because it tends to recur.
What causes blepharitis?
Blepharitis occurs in two forms:
Anterior blepharitis affects the outside front of the eyelid, where the eyelashes are attached. The two most common causes of anterior blepharitis are bacteria (Staphylococcus) and scalp dandruff.
Posterior blepharitis affects the inner eyelid (the moist part that makes contact with the eye) and is caused by problems with the oil (meibomian) glands in this part of the eyelid. Two skin disorders can cause this form of blepharitis: acne rosacea, which leads to red and inflamed skin, and scalp dandruff (seborrheic dermatitis).
What are the symptoms of blepharitis?
Symptoms of either form of blepharitis include a foreign body or burning sensation, excessive tearing, itching, sensitivity to light (photophobia), red and swollen eyelids, redness of the eye, blurred vision, frothy tears, dry eye, or crusting of the eyelashes on awakening.
What other conditions are associated with blepharitis?
Complications from blepharitis include:
Stye: A red tender bump on the eyelid that is caused by an acute infection of the oil glands of the eyelid.
Chalazion: This condition can follow the development of a stye. It is a usually painless firm lump caused by inflammation of the oil glands of the eyelid. Chalazion can be painful and red if there is also an infection.
Problems with the tear film: Abnormal or decreased oil secretions that are part of the tear film can result in excess tearing or dry eye. Because tears are necessary to keep the cornea healthy, tear film problems can make people more at risk for corneal infections.
How is blepharitis treated?
Treatment for both forms of blepharitis involves keeping the lids clean and free of crusts. Warm compresses should be applied to the lid to loosen the crusts, followed by a light scrubbing of the eyelid with a cotton swab and a mixture of water and baby shampoo. Because blepharitis rarely goes away completely, most patients must maintain an eyelid hygiene routine for life. If the blepharitis is severe, an eye care professional may also prescribe antibiotics or steroid eyedrops.
When scalp dandruff is present, a dandruff shampoo for the hair is recommended as well. In addition to the warm compresses, patients with posterior blepharitis will need to massage their eyelids to clean the oil accumulated in the glands. Patients who also have acne rosacea should have that condition treated at the same time.
What is blepharitis? Blepharitis is a common condition that causes inflammation of the eyelids. The condition can be difficult to manage because it tends to recur. What causes blepharitis? Blepharitis occurs in two forms: Anterior blepharitis affects the outside front of the eyelid, where the eyelashes are attached. The two most common causes of anterior blepharitis are bacteria (Staphylococcus) and scalp dandruff. Posterior blepharitis affects the inner eyelid (the moist part that makes contact with the eye) and is caused by problems with the oil (meibomian) glands in this part of the eyelid. Two skin disorders can cause this form of blepharitis: acne rosacea, which leads to red and inflamed skin, and scalp dandruff (seborrheic dermatitis). What are the symptoms of blepharitis? Symptoms of either form of blepharitis include a foreign body or burning sensation, excessive tearing, itching, sensitivity to light (photophobia), red and swollen eyelids, redness of the eye, blurred vision, frothy tears, dry eye, or crusting of the eyelashes on awakening. What other conditions are associated with blepharitis?
Blepharitis is a common condition that causes inflammation of the eyelids. The condition can be difficult to manage because it tends to recur.
What causes blepharitis?
Blepharitis occurs in two forms:
Anterior blepharitis affects the outside front of the eyelid, where the eyelashes are attached. The two most common causes of anterior blepharitis are bacteria (Staphylococcus) and scalp dandruff.
Posterior blepharitis affects the inner eyelid (the moist part that makes contact with the eye) and is caused by problems with the oil (meibomian) glands in this part of the eyelid. Two skin disorders can cause this form of blepharitis: acne rosacea, which leads to red and inflamed skin, and scalp dandruff (seborrheic dermatitis).
What are the symptoms of blepharitis?
Symptoms of either form of blepharitis include a foreign body or burning sensation, excessive tearing, itching, sensitivity to light (photophobia), red and swollen eyelids, redness of the eye, blurred vision, frothy tears, dry eye, or crusting of the eyelashes on awakening.
What other conditions are associated with blepharitis?
Complications from blepharitis include:
Stye: A red tender bump on the eyelid that is caused by an acute infection of the oil glands of the eyelid.
Chalazion: This condition can follow the development of a stye. It is a usually painless firm lump caused by inflammation of the oil glands of the eyelid. Chalazion can be painful and red if there is also an infection.
Problems with the tear film: Abnormal or decreased oil secretions that are part of the tear film can result in excess tearing or dry eye. Because tears are necessary to keep the cornea healthy, tear film problems can make people more at risk for corneal infections.
How is blepharitis treated?
Treatment for both forms of blepharitis involves keeping the lids clean and free of crusts. Warm compresses should be applied to the lid to loosen the crusts, followed by a light scrubbing of the eyelid with a cotton swab and a mixture of water and baby shampoo. Because blepharitis rarely goes away completely, most patients must maintain an eyelid hygiene routine for life. If the blepharitis is severe, an eye care professional may also prescribe antibiotics or steroid eyedrops.
When scalp dandruff is present, a dandruff shampoo for the hair is recommended as well. In addition to the warm compresses, patients with posterior blepharitis will need to massage their eyelids to clean the oil accumulated in the glands. Patients who also have acne rosacea should have that condition treated at the same time.
What is blepharitis? Blepharitis is a common condition that causes inflammation of the eyelids. The condition can be difficult to manage because it tends to recur. What causes blepharitis? Blepharitis occurs in two forms: Anterior blepharitis affects the outside front of the eyelid, where the eyelashes are attached. The two most common causes of anterior blepharitis are bacteria (Staphylococcus) and scalp dandruff. Posterior blepharitis affects the inner eyelid (the moist part that makes contact with the eye) and is caused by problems with the oil (meibomian) glands in this part of the eyelid. Two skin disorders can cause this form of blepharitis: acne rosacea, which leads to red and inflamed skin, and scalp dandruff (seborrheic dermatitis). What are the symptoms of blepharitis? Symptoms of either form of blepharitis include a foreign body or burning sensation, excessive tearing, itching, sensitivity to light (photophobia), red and swollen eyelids, redness of the eye, blurred vision, frothy tears, dry eye, or crusting of the eyelashes on awakening. What other conditions are associated with blepharitis?
Benign essential blepharospasm, hemifacial spasm
What is Blepharospasm?
Blepharospasm is an abnormal, involuntary blinking or spasm of the eyelids.
What causes Blepharospasm?
Blepharospasm is associated with an abnormal function of the basal ganglion from an unknown cause. The basal ganglion is the part of the brain responsible for controlling the muscles. In rare cases, heredity may play a role in the development of blepharospasm.
What are the symptoms of Blepharospasm?
Most people develop blepharospasm without any warning symptoms. It may begin with a gradual increase in blinking or eye irritation. Some people may also experience fatigue, emotional tension, or sensitivity to bright light. As the condition progresses, the symptoms become more frequent, and facial spasms may develop. Blepharospasm may decrease or cease while a person is sleeping or concentrating on a specific task.
How is Blepharospasm treated?
To date, there is no successful cure for blepharospasm, although several treatment options can reduce its severity.
In the United States and Canada, the injection of Oculinum (botulinum toxin, or Botox) into the muscles of the eyelids is an approved treatment for blepharospasm. Botulinum toxin, produced by the bacterium Clostridium botulinum, paralyzes the muscles of the eyelids.
Medications taken by mouth for blepharospasm are available but usually produce unpredictable results. Any symptom relief is usually short term and tends to be helpful in only 15 percent of the cases.
Myectomy, a surgical procedure to remove some of the muscles and nerves of the eyelids, is also a possible treatment option. This surgery has improved symptoms in 75 to 85 percent of people with blepharospasm.
Alternative treatments may include biofeedback, acupuncture, hypnosis, chiropractic, and nutritional therapy. The benefits of these alternative therapies have not been proven.
What is Blepharospasm? Blepharospasm is an abnormal, involuntary blinking or spasm of the eyelids. What causes Blepharospasm? Blepharospasm is associated with an abnormal function of the basal ganglion from an unknown cause. The basal ganglion is the part of the brain responsible for controlling the muscles. In rare cases, heredity may play a role in the development of blepharospasm. What are the symptoms of Blepharospasm? Most people develop blepharospasm without any warning symptoms. It may begin with a gradual increase in blinking or eye irritation. Some people may also experience fatigue, emotional tension, or sensitivity to bright light. As the condition progresses, the symptoms become more frequent, and facial spasms may develop. Blepharospasm may decrease or cease while a person is sleeping or concentrating on a specific task. How is Blepharospasm treated? To date, there is no successful cure for blepharospasm, although several treatment options can reduce its severity. In the United States and Canada, the injection of Oculinum (botulinum toxin, or Botox) into the muscles of the eyelids is an approved treatment for blepharospasm. Botulinum toxin, produced by the bacterium Clostridium botulinum, paralyzes the muscles of the eyelids. Medications taken by mouth
Blepharospasm is an abnormal, involuntary blinking or spasm of the eyelids.
What causes Blepharospasm?
Blepharospasm is associated with an abnormal function of the basal ganglion from an unknown cause. The basal ganglion is the part of the brain responsible for controlling the muscles. In rare cases, heredity may play a role in the development of blepharospasm.
What are the symptoms of Blepharospasm?
Most people develop blepharospasm without any warning symptoms. It may begin with a gradual increase in blinking or eye irritation. Some people may also experience fatigue, emotional tension, or sensitivity to bright light. As the condition progresses, the symptoms become more frequent, and facial spasms may develop. Blepharospasm may decrease or cease while a person is sleeping or concentrating on a specific task.
How is Blepharospasm treated?
To date, there is no successful cure for blepharospasm, although several treatment options can reduce its severity.
In the United States and Canada, the injection of Oculinum (botulinum toxin, or Botox) into the muscles of the eyelids is an approved treatment for blepharospasm. Botulinum toxin, produced by the bacterium Clostridium botulinum, paralyzes the muscles of the eyelids.
Medications taken by mouth for blepharospasm are available but usually produce unpredictable results. Any symptom relief is usually short term and tends to be helpful in only 15 percent of the cases.
Myectomy, a surgical procedure to remove some of the muscles and nerves of the eyelids, is also a possible treatment option. This surgery has improved symptoms in 75 to 85 percent of people with blepharospasm.
Alternative treatments may include biofeedback, acupuncture, hypnosis, chiropractic, and nutritional therapy. The benefits of these alternative therapies have not been proven.
What is Blepharospasm? Blepharospasm is an abnormal, involuntary blinking or spasm of the eyelids. What causes Blepharospasm? Blepharospasm is associated with an abnormal function of the basal ganglion from an unknown cause. The basal ganglion is the part of the brain responsible for controlling the muscles. In rare cases, heredity may play a role in the development of blepharospasm. What are the symptoms of Blepharospasm? Most people develop blepharospasm without any warning symptoms. It may begin with a gradual increase in blinking or eye irritation. Some people may also experience fatigue, emotional tension, or sensitivity to bright light. As the condition progresses, the symptoms become more frequent, and facial spasms may develop. Blepharospasm may decrease or cease while a person is sleeping or concentrating on a specific task. How is Blepharospasm treated? To date, there is no successful cure for blepharospasm, although several treatment options can reduce its severity. In the United States and Canada, the injection of Oculinum (botulinum toxin, or Botox) into the muscles of the eyelids is an approved treatment for blepharospasm. Botulinum toxin, produced by the bacterium Clostridium botulinum, paralyzes the muscles of the eyelids. Medications taken by mouth
diabetic eye disease
Diabetic Retinopathy Defined
What is diabetic eye disease?
Diabetic eye disease refers to a group of eye problems that people with diabetes may face as a complication of diabetes. All can cause severe vision loss or even blindness.
Diabetic eye disease may include:
Diabetic retinopathy—damage to the blood vessels in the retina.
Cataract—clouding of the eye's lens. Cataracts develop at an earlier age in people with diabetes.
Glaucoma—increase in fluid pressure inside the eye that leads to optic nerve damage and loss of vision. A person with diabetes is nearly twice as likely to get glaucoma as other adults.
What is diabetic retinopathy?
Diabetic retinopathy is the most common diabetic eye disease and a leading cause of blindness in American adults. It is caused by changes in the blood vessels of the retina.
In some people with diabetic retinopathy, blood vessels may swell and leak fluid. In other people, abnormal new blood vessels grow on the surface of the retina. The retina is the light-sensitive tissue at the back of the eye. A healthy retina is necessary for good vision.
If you have diabetic retinopathy, at first you may not notice changes to your vision. But over time, diabetic retinopathy can get worse and cause vision loss. Diabetic retinopathy usually affects both eyes.
What are the stages of diabetic retinopathy?
Diabetic retinopathy has four stages:
Mild Nonproliferative Retinopathy. At this earliest stage, microaneurysms occur. They are small areas of balloon-like swelling in the retina's tiny blood vessels.
Moderate Nonproliferative Retinopathy. As the disease progresses, some blood vessels that nourish the retina are blocked.
Severe Nonproliferative Retinopathy. Many more blood vessels are blocked, depriving several areas of the retina with their blood supply. These areas of the retina send signals to the body to grow new blood vessels for nourishment.
Proliferative Retinopathy. At this advanced stage, the signals sent by the retina for nourishment trigger the growth of new blood vessels. This condition is called proliferative retinopathy. These new blood vessels are abnormal and fragile. They grow along the retina and along the surface of the clear, vitreous gel that fills the inside of the eye. By themselves, these blood vessels do not cause symptoms or vision loss. However, they have thin, fragile walls. If they leak blood, severe vision loss and even blindness can result.
Causes and Risk Factors
How does diabetic retinopathy cause vision loss?
Blood vessels damaged from diabetic retinopathy can cause vision loss in two ways:
Fragile, abnormal blood vessels can develop and leak blood into the center of the eye, blurring vision. This is proliferative retinopathy and is the fourth and most advanced stage of the disease.
Fluid can leak into the center of the macula, the part of the eye where sharp, straight-ahead vision occurs. The fluid makes the macula swell, blurring vision. This condition is called macular edema. It can occur at any stage of diabetic retinopathy, although it is more likely to occur as the disease progresses. About half of the people with proliferative retinopathy also have macular edema
Who is at risk for diabetic retinopathy?
All people with diabetes--both type 1 and type 2--are at risk. That's why everyone with diabetes should get a comprehensive dilated eye exam at least once a year. The longer someone has diabetes, the more likely he or she will get diabetic retinopathy. Between 40 to 45 percent of Americans diagnosed with diabetes have some stage of diabetic retinopathy. If you have diabetic retinopathy, your doctor can recommend treatment to help prevent its progression.
During pregnancy, diabetic retinopathy may be a problem for women with diabetes. To protect vision, every pregnant woman with diabetes should have a comprehensive dilated eye exam as soon as possible. Your doctor may recommend additional exams during your pregnancy.
What can I do to protect my vision?
If you have diabetes get a comprehensive dilated eye exam at least once a year and remember:
Proliferative retinopathy can develop without symptoms. At this advanced stage, you are at high risk for vision loss.
Macular edema can develop without symptoms at any of the four stages of diabetic retinopathy.
You can develop both proliferative retinopathy and macular edema and still see fine. However, you are at high risk for vision loss.
Your eye care professional can tell if you have macular edema or any stage of diabetic retinopathy. Whether or not you have symptoms, early detection and timely treatment can prevent vision loss.
If you have diabetic retinopathy, you may need an eye exam more often. People with proliferative retinopathy can reduce their risk of blindness by 95 percent with timely treatment and appropriate follow-up care.
The Diabetes Control and Complications Trial (DCCT) showed that better control of blood sugar levels slows the onset and progression of retinopathy. The people with diabetes who kept their blood sugar levels as close to normal as possible also had much less kidney and nerve disease. Better control also reduces the need for sight-saving laser surgery.
This level of blood sugar control may not be best for everyone, including some elderly patients, children under age 13, or people with heart disease. Be sure to ask your doctor if such a control program is right for you.
Other studies have shown that controlling elevated blood pressure and cholesterol can reduce the risk of vision loss. Controlling these will help your overall health as well as help protect your vision.
Symptoms and Detection
Does diabetic retinopathy have any symptoms?
Often there are no symptoms in the early stages of the disease, nor is there any pain. Don't wait for symptoms. Be sure to have a comprehensive dilated eye exam at least once a year.
Blurred vision may occur when the macula—the part of the retina that provides sharp central vision—swells from leaking fluid. This condition is called macular edema.
If new blood vessels grow on the surface of the retina, they can bleed into the eye and block vision.
What are the symptoms of proliferative retinopathy if bleeding occurs?
At first, you will see a few specks of blood, or spots, "floating" in your vision. If spots occur, see your eye care professional as soon as possible. You may need treatment before more serious bleeding occurs. Hemorrhages tend to happen more than once, often during sleep.
Sometimes, without treatment, the spots clear, and you will see better. However, bleeding can reoccur and cause severely blurred vision. You need to be examined by your eye care professional at the first sign of blurred vision, before more bleeding occurs.
If left untreated, proliferative retinopathy can cause severe vision loss and even blindness. Also, the earlier you receive treatment, the more likely treatment will be effective.
How are diabetic retinopathy and macular edema detected?
Diabetic retinopathy and macular edema are detected during a comprehensive eye exam that includes:
Visual acuity test. This eye chart test measures how well you see at various distances.
Dilated eye exam. Drops are placed in your eyes to widen, or dilate, the pupils. This allows the eye care professional to see more of the inside of your eyes to check for signs of the disease. Your eye care professional uses a special magnifying lens to examine your retina and optic nerve for signs of damage and other eye problems. After the exam, your close-up vision may remain blurred for several hours.
Tonometry. An instrument measures the pressure inside the eye. Numbing drops may be applied to your eye for this test.
Your eye care professional checks your retina for early signs of the disease, including:
Leaking blood vessels.
Retinal swelling (macular edema).
Pale, fatty deposits on the retina--signs of leaking blood vessels.
Damaged nerve tissue.
Any changes to the blood vessels.
If your eye care professional believes you need treatment for macular edema, he or she may suggest a fluorescein angiogram. In this test, a special dye is injected into your arm. Pictures are taken as the dye passes through the blood vessels in your retina. The test allows your eye care professional to identify any leaking blood vessels and recommend treatment.
Treatment
How is diabetic retinopathy treated?
During the first three stages of diabetic retinopathy, no treatment is needed, unless you have macular edema. To prevent progression of diabetic retinopathy, people with diabetes should control their levels of blood sugar, blood pressure, and blood cholesterol.
Proliferative retinopathy is treated with laser surgery. This procedure is called scatter laser treatment. Scatter laser treatment helps to shrink the abnormal blood vessels. Your doctor places 1,000 to 2,000 laser burns in the areas of the retina away from the macula, causing the abnormal blood vessels to shrink. Because a high number of laser burns are necessary, two or more sessions usually are required to complete treatment. Although you may notice some loss of your side vision, scatter laser treatment can save the rest of your sight. Scatter laser treatment may slightly reduce your color vision and night vision.
Scatter laser treatment works better before the fragile, new blood vessels have started to bleed. That is why it is important to have regular, comprehensive dilated eye exams. Even if bleeding has started, scatter laser treatment may still be possible, depending on the amount of bleeding.
If the bleeding is severe, you may need a surgical procedure called a vitrectomy. During a vitrectomy, blood is removed from the center of your eye.
How is a macular edema treated?
Macular edema is treated with laser surgery. This procedure is called focal laser treatment. Your doctor places up to several hundred small laser burns in the areas of retinal leakage surrounding the macula. These burns slow the leakage of fluid and reduce the amount of fluid in the retina. The surgery is usually completed in one session. Further treatment may be needed.
A patient may need focal laser surgery more than once to control the leaking fluid. If you have macular edema in both eyes and require laser surgery, generally only one eye will be treated at a time, usually several weeks apart.
Focal laser treatment stabilizes vision. In fact, focal laser treatment reduces the risk of vision loss by 50 percent. In a small number of cases, if vision is lost, it can be improved. Contact your eye care professional if you have vision loss.
What happens during laser treatment?
Both focal and scatter laser treatment are performed in your doctor's office or eye clinic. Before the surgery, your doctor will dilate your pupil and apply drops to numb the eye. The area behind your eye also may be numbed to prevent discomfort.
The lights in the office will be dim. As you sit facing the laser machine, your doctor will hold a special lens to your eye. During the procedure, you may see flashes of light. These flashes eventually may create a stinging sensation that can be uncomfortable. You will need someone to drive you home after surgery. Because your pupil will remain dilated for a few hours, you should bring a pair of sunglasses.
For the rest of the day, your vision will probably be a little blurry. If your eye hurts, your doctor can suggest treatment.
Laser surgery and appropriate follow-up care can reduce the risk of blindness by 90 percent. However, laser surgery often cannot restore vision that has already been lost. That is why finding diabetic retinopathy early is the best way to prevent vision loss.
What is a vitrectomy?
If you have a lot of blood in the center of the eye (vitreous gel), you may need a vitrectomy to restore your sight. If you need vitrectomies in both eyes, they are usually done several weeks apart.
A vitrectomy is performed under either local or general anesthesia. Your doctor makes a tiny incision in your eye. Next, a small instrument is used to remove the vitreous gel that is clouded with blood. The vitreous gel is replaced with a salt solution. Because the vitreous gel is mostly water, you will notice no change between the salt solution and the original vitreous gel.
You will probably be able to return home after the vitrectomy. Some people stay in the hospital overnight. Your eye will be red and sensitive. You will need to wear an eye patch for a few days or weeks to protect your eye. You also will need to use medicated eyedrops to protect against infection.
Are scatter laser treatment and vitrectomy effective in treating proliferative retinopathy?
Yes. Both treatments are very effective in reducing vision loss. People with proliferative retinopathy have less than a five percent chance of becoming blind within five years when they get timely and appropriate treatment. Although both treatments have high success rates, they do not cure diabetic retinopathy.
Once you have proliferative retinopathy, you always will be at risk for new bleeding. You may need treatment more than once to protect your sight.
What can I do if I already have lost some vision from diabetic retinopathy?
If you have lost some sight from diabetic retinopathy, ask your eye care professional about low vision services and devices that may help you make the most of your remaining vision. Ask for a referral to a specialist in low vision. Many community organizations and agencies offer information about low vision counseling, training, and other special services for people with visual impairments. A nearby school of medicine or optometry may provide low vision services.
Diabetic Retinopathy Defined What is diabetic eye disease? Diabetic eye disease refers to a group of eye problems that people with diabetes may face as a complication of diabetes. All can cause severe vision loss or even blindness. Diabetic eye disease may include: Diabetic retinopathy—damage to the blood vessels in the retina. Cataract—clouding of the eye's lens. Cataracts develop at an earlier age in people with diabetes. Glaucoma—increase in fluid pressure inside the eye that leads to optic nerve damage and loss of vision. A person with diabetes is nearly twice as likely to get glaucoma as other adults. What is diabetic retinopathy? Diabetic retinopathy is the most common diabetic eye disease and a leading cause of blindness in American adults. It is caused by changes in the blood vessels of the retina. In some people with diabetic retinopathy, blood vessels may swell and leak fluid. In other people, abnormal new blood vessels grow on the surface of the retina. The retina is the light-sensitive tissue at the back of the eye. A healthy retina is necessary for good vision. If you have diabetic retinopathy, at first you may not notice changes to your vision. But over time, diabetic retinopathy can get worse and cause vision loss. Diabetic retinopathy usually affects both eyes. What are the stages of diabetic retinopathy? Diabetic retinopathy has four stages: Mild Nonproliferative Retinopathy. At this earliest stage, microaneurysms occur. They are small areas of balloon-like swelling in the retina's tiny blood vessels. Moderate Nonproliferative Retinopathy. As the disease progresses, some blood vessels that nourish the retina are blocked. Severe Nonproliferative Retinopathy. Many more blood vessels are blocked, depriving several areas of the retina with their blood supply. These areas of the retina send signals to the body to grow new blood vessels for nourishment. Proliferative Retinopathy. At this advanced stage, the signals sent by the retina for nourishment trigger the growth of new blood vessels. This condition is called proliferative retinopathy. These new blood vessels are abnormal and fragile. They grow along the retina and along the surface of the clear, vitreous gel that fills the inside of the eye. By themselves, these blood vessels do not cause symptoms or vision loss. However, they have thin, fragile walls. If they leak blood, severe vision loss and even blindness can result. Causes and Risk Factors How does diabetic retinopathy cause vision loss? Blood vessels damaged from diabetic retinopathy can cause vision loss in two ways: Fragile, abnormal blood vessels can develop and leak blood into the center of the eye, blurring vision. This is proliferative retinopathy and is the fourth and most advanced stage of the disease. Fluid can leak into the center of the macula, the part of the eye where sharp, straight-ahead vision occurs. The fluid makes the macula swell, blurring vision. This condition is called macular edema. It can occur at any stage of diabetic retinopathy, although it is more likely to occur as the disease progresses. About half of the people with proliferative retinopathy also have macular edema Who is at risk for diabetic retinopathy?
What is diabetic eye disease?
Diabetic eye disease refers to a group of eye problems that people with diabetes may face as a complication of diabetes. All can cause severe vision loss or even blindness.
Diabetic eye disease may include:
Diabetic retinopathy—damage to the blood vessels in the retina.
Cataract—clouding of the eye's lens. Cataracts develop at an earlier age in people with diabetes.
Glaucoma—increase in fluid pressure inside the eye that leads to optic nerve damage and loss of vision. A person with diabetes is nearly twice as likely to get glaucoma as other adults.
What is diabetic retinopathy?
Diabetic retinopathy is the most common diabetic eye disease and a leading cause of blindness in American adults. It is caused by changes in the blood vessels of the retina.
In some people with diabetic retinopathy, blood vessels may swell and leak fluid. In other people, abnormal new blood vessels grow on the surface of the retina. The retina is the light-sensitive tissue at the back of the eye. A healthy retina is necessary for good vision.
If you have diabetic retinopathy, at first you may not notice changes to your vision. But over time, diabetic retinopathy can get worse and cause vision loss. Diabetic retinopathy usually affects both eyes.
What are the stages of diabetic retinopathy?
Diabetic retinopathy has four stages:
Mild Nonproliferative Retinopathy. At this earliest stage, microaneurysms occur. They are small areas of balloon-like swelling in the retina's tiny blood vessels.
Moderate Nonproliferative Retinopathy. As the disease progresses, some blood vessels that nourish the retina are blocked.
Severe Nonproliferative Retinopathy. Many more blood vessels are blocked, depriving several areas of the retina with their blood supply. These areas of the retina send signals to the body to grow new blood vessels for nourishment.
Proliferative Retinopathy. At this advanced stage, the signals sent by the retina for nourishment trigger the growth of new blood vessels. This condition is called proliferative retinopathy. These new blood vessels are abnormal and fragile. They grow along the retina and along the surface of the clear, vitreous gel that fills the inside of the eye. By themselves, these blood vessels do not cause symptoms or vision loss. However, they have thin, fragile walls. If they leak blood, severe vision loss and even blindness can result.
Causes and Risk Factors
How does diabetic retinopathy cause vision loss?
Blood vessels damaged from diabetic retinopathy can cause vision loss in two ways:
Fragile, abnormal blood vessels can develop and leak blood into the center of the eye, blurring vision. This is proliferative retinopathy and is the fourth and most advanced stage of the disease.
Fluid can leak into the center of the macula, the part of the eye where sharp, straight-ahead vision occurs. The fluid makes the macula swell, blurring vision. This condition is called macular edema. It can occur at any stage of diabetic retinopathy, although it is more likely to occur as the disease progresses. About half of the people with proliferative retinopathy also have macular edema
Who is at risk for diabetic retinopathy?
All people with diabetes--both type 1 and type 2--are at risk. That's why everyone with diabetes should get a comprehensive dilated eye exam at least once a year. The longer someone has diabetes, the more likely he or she will get diabetic retinopathy. Between 40 to 45 percent of Americans diagnosed with diabetes have some stage of diabetic retinopathy. If you have diabetic retinopathy, your doctor can recommend treatment to help prevent its progression.
During pregnancy, diabetic retinopathy may be a problem for women with diabetes. To protect vision, every pregnant woman with diabetes should have a comprehensive dilated eye exam as soon as possible. Your doctor may recommend additional exams during your pregnancy.
What can I do to protect my vision?
If you have diabetes get a comprehensive dilated eye exam at least once a year and remember:
Proliferative retinopathy can develop without symptoms. At this advanced stage, you are at high risk for vision loss.
Macular edema can develop without symptoms at any of the four stages of diabetic retinopathy.
You can develop both proliferative retinopathy and macular edema and still see fine. However, you are at high risk for vision loss.
Your eye care professional can tell if you have macular edema or any stage of diabetic retinopathy. Whether or not you have symptoms, early detection and timely treatment can prevent vision loss.
If you have diabetic retinopathy, you may need an eye exam more often. People with proliferative retinopathy can reduce their risk of blindness by 95 percent with timely treatment and appropriate follow-up care.
The Diabetes Control and Complications Trial (DCCT) showed that better control of blood sugar levels slows the onset and progression of retinopathy. The people with diabetes who kept their blood sugar levels as close to normal as possible also had much less kidney and nerve disease. Better control also reduces the need for sight-saving laser surgery.
This level of blood sugar control may not be best for everyone, including some elderly patients, children under age 13, or people with heart disease. Be sure to ask your doctor if such a control program is right for you.
Other studies have shown that controlling elevated blood pressure and cholesterol can reduce the risk of vision loss. Controlling these will help your overall health as well as help protect your vision.
Symptoms and Detection
Does diabetic retinopathy have any symptoms?
Often there are no symptoms in the early stages of the disease, nor is there any pain. Don't wait for symptoms. Be sure to have a comprehensive dilated eye exam at least once a year.
Blurred vision may occur when the macula—the part of the retina that provides sharp central vision—swells from leaking fluid. This condition is called macular edema.
If new blood vessels grow on the surface of the retina, they can bleed into the eye and block vision.
What are the symptoms of proliferative retinopathy if bleeding occurs?
At first, you will see a few specks of blood, or spots, "floating" in your vision. If spots occur, see your eye care professional as soon as possible. You may need treatment before more serious bleeding occurs. Hemorrhages tend to happen more than once, often during sleep.
Sometimes, without treatment, the spots clear, and you will see better. However, bleeding can reoccur and cause severely blurred vision. You need to be examined by your eye care professional at the first sign of blurred vision, before more bleeding occurs.
If left untreated, proliferative retinopathy can cause severe vision loss and even blindness. Also, the earlier you receive treatment, the more likely treatment will be effective.
How are diabetic retinopathy and macular edema detected?
Diabetic retinopathy and macular edema are detected during a comprehensive eye exam that includes:
Visual acuity test. This eye chart test measures how well you see at various distances.
Dilated eye exam. Drops are placed in your eyes to widen, or dilate, the pupils. This allows the eye care professional to see more of the inside of your eyes to check for signs of the disease. Your eye care professional uses a special magnifying lens to examine your retina and optic nerve for signs of damage and other eye problems. After the exam, your close-up vision may remain blurred for several hours.
Tonometry. An instrument measures the pressure inside the eye. Numbing drops may be applied to your eye for this test.
Your eye care professional checks your retina for early signs of the disease, including:
Leaking blood vessels.
Retinal swelling (macular edema).
Pale, fatty deposits on the retina--signs of leaking blood vessels.
Damaged nerve tissue.
Any changes to the blood vessels.
If your eye care professional believes you need treatment for macular edema, he or she may suggest a fluorescein angiogram. In this test, a special dye is injected into your arm. Pictures are taken as the dye passes through the blood vessels in your retina. The test allows your eye care professional to identify any leaking blood vessels and recommend treatment.
Treatment
How is diabetic retinopathy treated?
During the first three stages of diabetic retinopathy, no treatment is needed, unless you have macular edema. To prevent progression of diabetic retinopathy, people with diabetes should control their levels of blood sugar, blood pressure, and blood cholesterol.
Proliferative retinopathy is treated with laser surgery. This procedure is called scatter laser treatment. Scatter laser treatment helps to shrink the abnormal blood vessels. Your doctor places 1,000 to 2,000 laser burns in the areas of the retina away from the macula, causing the abnormal blood vessels to shrink. Because a high number of laser burns are necessary, two or more sessions usually are required to complete treatment. Although you may notice some loss of your side vision, scatter laser treatment can save the rest of your sight. Scatter laser treatment may slightly reduce your color vision and night vision.
Scatter laser treatment works better before the fragile, new blood vessels have started to bleed. That is why it is important to have regular, comprehensive dilated eye exams. Even if bleeding has started, scatter laser treatment may still be possible, depending on the amount of bleeding.
If the bleeding is severe, you may need a surgical procedure called a vitrectomy. During a vitrectomy, blood is removed from the center of your eye.
How is a macular edema treated?
Macular edema is treated with laser surgery. This procedure is called focal laser treatment. Your doctor places up to several hundred small laser burns in the areas of retinal leakage surrounding the macula. These burns slow the leakage of fluid and reduce the amount of fluid in the retina. The surgery is usually completed in one session. Further treatment may be needed.
A patient may need focal laser surgery more than once to control the leaking fluid. If you have macular edema in both eyes and require laser surgery, generally only one eye will be treated at a time, usually several weeks apart.
Focal laser treatment stabilizes vision. In fact, focal laser treatment reduces the risk of vision loss by 50 percent. In a small number of cases, if vision is lost, it can be improved. Contact your eye care professional if you have vision loss.
What happens during laser treatment?
Both focal and scatter laser treatment are performed in your doctor's office or eye clinic. Before the surgery, your doctor will dilate your pupil and apply drops to numb the eye. The area behind your eye also may be numbed to prevent discomfort.
The lights in the office will be dim. As you sit facing the laser machine, your doctor will hold a special lens to your eye. During the procedure, you may see flashes of light. These flashes eventually may create a stinging sensation that can be uncomfortable. You will need someone to drive you home after surgery. Because your pupil will remain dilated for a few hours, you should bring a pair of sunglasses.
For the rest of the day, your vision will probably be a little blurry. If your eye hurts, your doctor can suggest treatment.
Laser surgery and appropriate follow-up care can reduce the risk of blindness by 90 percent. However, laser surgery often cannot restore vision that has already been lost. That is why finding diabetic retinopathy early is the best way to prevent vision loss.
What is a vitrectomy?
If you have a lot of blood in the center of the eye (vitreous gel), you may need a vitrectomy to restore your sight. If you need vitrectomies in both eyes, they are usually done several weeks apart.
A vitrectomy is performed under either local or general anesthesia. Your doctor makes a tiny incision in your eye. Next, a small instrument is used to remove the vitreous gel that is clouded with blood. The vitreous gel is replaced with a salt solution. Because the vitreous gel is mostly water, you will notice no change between the salt solution and the original vitreous gel.
You will probably be able to return home after the vitrectomy. Some people stay in the hospital overnight. Your eye will be red and sensitive. You will need to wear an eye patch for a few days or weeks to protect your eye. You also will need to use medicated eyedrops to protect against infection.
Are scatter laser treatment and vitrectomy effective in treating proliferative retinopathy?
Yes. Both treatments are very effective in reducing vision loss. People with proliferative retinopathy have less than a five percent chance of becoming blind within five years when they get timely and appropriate treatment. Although both treatments have high success rates, they do not cure diabetic retinopathy.
Once you have proliferative retinopathy, you always will be at risk for new bleeding. You may need treatment more than once to protect your sight.
What can I do if I already have lost some vision from diabetic retinopathy?
If you have lost some sight from diabetic retinopathy, ask your eye care professional about low vision services and devices that may help you make the most of your remaining vision. Ask for a referral to a specialist in low vision. Many community organizations and agencies offer information about low vision counseling, training, and other special services for people with visual impairments. A nearby school of medicine or optometry may provide low vision services.
Diabetic Retinopathy Defined What is diabetic eye disease? Diabetic eye disease refers to a group of eye problems that people with diabetes may face as a complication of diabetes. All can cause severe vision loss or even blindness. Diabetic eye disease may include: Diabetic retinopathy—damage to the blood vessels in the retina. Cataract—clouding of the eye's lens. Cataracts develop at an earlier age in people with diabetes. Glaucoma—increase in fluid pressure inside the eye that leads to optic nerve damage and loss of vision. A person with diabetes is nearly twice as likely to get glaucoma as other adults. What is diabetic retinopathy? Diabetic retinopathy is the most common diabetic eye disease and a leading cause of blindness in American adults. It is caused by changes in the blood vessels of the retina. In some people with diabetic retinopathy, blood vessels may swell and leak fluid. In other people, abnormal new blood vessels grow on the surface of the retina. The retina is the light-sensitive tissue at the back of the eye. A healthy retina is necessary for good vision. If you have diabetic retinopathy, at first you may not notice changes to your vision. But over time, diabetic retinopathy can get worse and cause vision loss. Diabetic retinopathy usually affects both eyes. What are the stages of diabetic retinopathy? Diabetic retinopathy has four stages: Mild Nonproliferative Retinopathy. At this earliest stage, microaneurysms occur. They are small areas of balloon-like swelling in the retina's tiny blood vessels. Moderate Nonproliferative Retinopathy. As the disease progresses, some blood vessels that nourish the retina are blocked. Severe Nonproliferative Retinopathy. Many more blood vessels are blocked, depriving several areas of the retina with their blood supply. These areas of the retina send signals to the body to grow new blood vessels for nourishment. Proliferative Retinopathy. At this advanced stage, the signals sent by the retina for nourishment trigger the growth of new blood vessels. This condition is called proliferative retinopathy. These new blood vessels are abnormal and fragile. They grow along the retina and along the surface of the clear, vitreous gel that fills the inside of the eye. By themselves, these blood vessels do not cause symptoms or vision loss. However, they have thin, fragile walls. If they leak blood, severe vision loss and even blindness can result. Causes and Risk Factors How does diabetic retinopathy cause vision loss? Blood vessels damaged from diabetic retinopathy can cause vision loss in two ways: Fragile, abnormal blood vessels can develop and leak blood into the center of the eye, blurring vision. This is proliferative retinopathy and is the fourth and most advanced stage of the disease. Fluid can leak into the center of the macula, the part of the eye where sharp, straight-ahead vision occurs. The fluid makes the macula swell, blurring vision. This condition is called macular edema. It can occur at any stage of diabetic retinopathy, although it is more likely to occur as the disease progresses. About half of the people with proliferative retinopathy also have macular edema Who is at risk for diabetic retinopathy?
dry eye
What is the cornea?
The cornea is the clear, dome-shaped outer surface that covers the eye in front of the iris, the colored part of the eye. The cornea helps protect the rest of the eye from germs, dust, and other harmful matter. The cornea bends, or refracts, light entering the eye, and accounts for most of the eye's total focusing power. It also serves as a filter to screen out most of the damaging ultraviolet (UV) wavelengths in sunlight.
The cornea is a highly organized, clear structure made up of a group of cells and proteins precisely arranged in layers, but it has no blood vessels to nourish or protect it against infection. Instead, it receives its nourishment from the tears and the watery fluid (aqueous humor) that fills the chamber behind it.-->
What is dry eye?
Dry eye occurs when the eye does not produce tears properly, or when the tears are not of the correct consistency and evaporate too quickly.
In addition, inflammation of the surface of the eye may occur along with dry eye. If left untreated, this condition can lead to pain, ulcers, or scars on the cornea, and some loss of vision. However, permanent loss of vision from dry eye is uncommon.
Dry eye can make it more difficult to perform some activities, such as using a computer or reading for an extended period of time, and it can decrease tolerance for dry environments, such as the air inside an airplane.
What are tears, and how do they relate to dry eye?
Tears, made by the lacrimal gland, are necessary for overall eye health and clear vision. Tears bathe the surface of the eye, keeping it moist, and wash away dust and debris. They also help protect the eye from bacterial and other types of infections.
Tears are composed of three major components: a) outer, oily, lipid layer produced by the meibomian glands; b) middle, watery, lacrimal layer produced by the lacrimal glands; and c) inner, mucous or mucin layer produced by goblet cells located within a thin transparent layer over the white part of the eye and covering the inner surface of the eyelids. Tears are made of proteins (including growth factors), electrolytes, and vitamins that are critical to maintain the health of the eye surface and to prevent infection.
Tears are constantly produced to bathe, nourish, and protect the eye surface. They are also produced in response to emergencies, such as a particle of dust in the eye, an infection or irritation of the eye, or an onset of strong emotions. When the lacrimal glands fail to produce sufficient tears, dry eye can result.
Any disease process that alters the components of tears can make them unhealthy and result in dry eye.
What are the types of dry eye?
1) Aqueous tear-deficient dry eye is a disorder in which the lacrimal glands fail to produce enough of the watery component of tears to maintain a healthy eye surface.
2) Evaporative dry eye may result from inflammation of the meibomian glands, also located in the eyelids. These glands make the lipid or oily part of tears that slows evaporation and keeps the tears stable.
Dry eye can be associated with:
inflammation of the surface of the eye, the lacrimal gland, or the conjunctiva;
any disease process that alters the components of the tears;
an increase in the surface of the eye, as in thyroid disease when the eye protrudes forward;
cosmetic surgery, if the eyelids are opened too widely.
What are the symptoms of dry eye?
Dry eye symptoms may include any of the following:
stinging or burning of the eye;
a sandy or gritty feeling as if something is in the eye;
episodes of excess tears following very dry eye periods;
a stringy discharge from the eye;
pain and redness of the eye;
episodes of blurred vision;
heavy eyelids;
inability to cry when emotionally stressed;
uncomfortable contact lenses;
decreased tolerance of reading, working on the computer, or any activity that requires sustained visual attention;
eye fatigue.
NOTE: If symptoms of dry eye persist, consult an eye care professional to get an accurate diagnosis of the condition and begin treatment to avoid permanent damage.
Who is likely to develop dry eye?
Elderly people frequently experience dryness of the eyes, but dry eye can occur at any age. Nearly five million Americans 50 years of age and older are estimated to have dry eye. Of these, more than three million are women and more than one and a half million are men. Tens of millions more have less severe symptoms. Dry eye is more common after menopause. Women who experience menopause prematurely are more likely to have eye surface damage from dry eye.
What are the causes of dry eye?
Dry eye can be a temporary or chronic condition:
Dry eye can be a side effect of some medications, including antihistamines, nasal decongestants, tranquilizers, certain blood pressure medicines, Parkinson's medications, birth control pills and anti-depressants.
Skin disease on or around the eyelids can result in dry eye.
Diseases of the glands in the eyelids, such as meibomian gland dysfunction, can cause dry eye.
Dry eye can occur in women who are pregnant.
Women who are on hormone replacement therapy may experience dry eye symptoms. Women taking only estrogen are 70 percent more likely to experience dry eye, whereas those taking estrogen and progesterone have a 30 percent increased risk of developing dry eye.
Dry eye can also develop after the refractive surgery known as LASIK. These symptoms generally last three to six months, but may last longer in some cases.
Dry eye can result from chemical and thermal burns that scar the membrane lining the eyelids and covering the eye.
Allergies can be associated with dry eye.
Infrequent blinking, associated with staring at computer or video screens, may also lead to dry eye symptoms.
Both excessive and insufficient dosages of vitamins can contribute to dry eye.
Homeopathic remedies may have an adverse impact on a dry eye condition.
Loss of sensation in the cornea from long-term contact lens wear can lead to dry eye.
Dry eye can be associated with immune system disorders such as Sjögren's syndrome, lupus, and rheumatoid arthritis. Sjögren's leads to inflammation and dryness of the mouth, eyes, and other mucous membranes. It can also affect other organs, including the kidneys, lungs and blood vessels.
Dry eye can be a symptom of chronic inflammation of the conjunctiva, the membrane lining the eyelid and covering the front part of the eye, or the lacrimal gland. Chronic conjunctivitis can be caused by certain eye diseases, infection, exposure to irritants such as chemical fumes and tobacco smoke, or drafts from air conditioning or heating.
If the surface area of the eye is increased, as in thyroid disease when the eye protrudes forward or after cosmetic surgery if the eyelids are opened too widely, dry eye can result.
Dry eye may occur from exposure keratitis, in which the eyelids do not close completely during sleep.
What can I do to help myself?
Use artificial tears, gels, gel inserts, and ointments - available over the counter - as the first line of therapy. They offer temporary relief and provide an important replacement of naturally produced tears in patients with aqueous tear deficiency. Avoid artificial tears with preservatives if you need to apply them more than four times a day or preparations with chemicals that cause blood vessels to constrict.
Wearing glasses or sunglasses that fit close to the face (wrap around shades) or that have side shields can help slow tear evaporation from the eye surfaces. Indoors, an air cleaner to filter dust and other particles helps prevent dry eyes. A humidifier also may help by adding moisture to the air.
Avoid dry conditions and allow your eyes to rest when performing activities that require you to use your eyes for long periods of time. Instill lubricating eye drops while performing these tasks.
How is dry eye treated?
Depending on the causes of dry eye, your doctor may use various approaches to relieve the symptoms.
Dry eye can be managed as an ongoing condition. The first priority is to determine if a disease is the underlying cause of the dry eye (such as Sjögren's syndrome or lacrimal and meibomian gland dysfunction). If it is, then the underlying disease needs to be treated.
Cyclosporine, an anti-inflammatory medication, is the only prescription drug available to treat dry eye. It decreases corneal damage, increases basic tear production, and reduces symptoms of dry eye. It may take three to six months of twice-a-day dosages for the medication to work. In some cases of severe dry eye, short term use of corticosteroid eye drops that decrease inflammation is required.
If dry eye results from taking a medication, your doctor may recommend switching to a medication that does not cause the dry eye side effect.
If contact lens wear is the problem, your eye care practitioner may recommend another type of lens or reducing the number of hours you wear your lenses. In the case of severe dry eye, your eye care professional may advise you not to wear contact lenses at all.
Another option is to plug the drainage holes, small circular openings at the inner corners of the eyelids where tears drain from the eye into the nose. Lacrimal plugs, also called punctal plugs, can be inserted painlessly by an eye care professional. The patient usually does not feel them. These plugs are made of silicone or collagen, are reversible, and are a temporary measure. In severe cases, permanent plugs may be considered.
In some cases, a simple surgery, called punctal cautery, is recommended to permanently close the drainage holes. The procedure helps keep the limited volume of tears on the eye for a longer period of time.
In some patients with dry eye, supplements or dietary sources (such as tuna fish) of omega-3 fatty acids (especially DHA and EPA) may decrease symptoms of irritation. The use and dosage of nutritional supplements and vitamins should be discussed with your primary medical doctor
What is the cornea? The cornea is the clear, dome-shaped outer surface that covers the eye in front of the iris, the colored part of the eye. The cornea helps protect the rest of the eye from germs, dust, and other harmful matter. The cornea bends, or refracts, light entering the eye, and accounts for most of the eye's total focusing power. It also serves as a filter to screen out most of the damaging ultraviolet (UV) wavelengths in sunlight. The cornea is a highly organized, clear structure made up of a group of cells and proteins precisely arranged in layers, but it has no blood vessels to nourish or protect it against infection. Instead, it receives its nourishment from the tears and the watery fluid (aqueous humor) that fills the chamber behind it.--> What is dry eye? Dry eye occurs when the eye does not produce tears properly, or when the tears are not of the correct consistency and evaporate too quickly. In addition, inflammation of the surface of the eye may occur along with dry eye. If left untreated, this condition can lead to pain, ulcers, or scars on the cornea, and some loss of vision. However, permanent loss of vision from dry eye is uncommon. Dry eye can make it more difficult to perform some activities, such as using a computer or reading for an extended period of time, and it can decrease tolerance for dry environments, such as the air inside an airplane. What are tears, and how do they relate to dry eye? Tears, made by the lacrimal gland, are necessary for overall eye health and clear vision. Tears bathe the surface of the eye, keeping it moist, and wash away dust and debris. They also help protect the eye from bacterial and other types of infections. Tears are composed of three major components: a) outer, oily, lipid layer produced by the meibomian glands; b) middle, watery, lacrimal layer produced by the lacrimal glands; and c) inner, mucous or mucin layer produced by goblet cells located within a thin transparent layer over the white part of the eye and covering the inner surface of the eyelids. Tears are made of proteins (including growth factors), electrolytes, and vitamins that are critical to maintain the health of the eye surface and to prevent infection. Tears are constantly produced to bathe, nourish, and protect the eye surface. They are also produced in response to emergencies, such as a particle of dust in the eye, an infection or irritation of the eye, or an onset of strong emotions. When the lacrimal glands fail to produce sufficient tears, dry eye can result. Any disease process that alters the components of tears can make them unhealthy and result in dry eye. What are the types of dry eye? 1) Aqueous tear-deficient dry eye is a disorder in which the lacrimal glands fail to produce enough of the watery component of tears to maintain a healthy eye surface. 2) Evaporative dry eye may result from inflammation of the meibomian glands, also located in the eyelids. These glands make the lipid or oily part of tears that slows evaporation and keeps the tears stable. Dry eye can be associated with: inflammation of the surface of the eye, the lacrimal gland, or the conjunctiva; any disease process that alters the components of the tears; an increase in the surface of the eye, as in thyroid disease when the eye protrudes forward; cosmetic surgery, if the eyelids are opened too widely. What are the symptoms of dry eye? Dry eye symptoms may include any of the following: stinging or burning of the eye; a sandy or gritty feeling as if something is in the eye; episodes of excess tears following very dry eye periods; a stringy discharge from the eye; pain and redness of the eye; episodes of blurred vision; heavy eyelids; inability to cry when emotionally stressed; uncomfortable contact lenses; decreased tolerance of reading, working on the computer, or any activity that requires sustained visual attention; eye fatigue.
The cornea is the clear, dome-shaped outer surface that covers the eye in front of the iris, the colored part of the eye. The cornea helps protect the rest of the eye from germs, dust, and other harmful matter. The cornea bends, or refracts, light entering the eye, and accounts for most of the eye's total focusing power. It also serves as a filter to screen out most of the damaging ultraviolet (UV) wavelengths in sunlight.
The cornea is a highly organized, clear structure made up of a group of cells and proteins precisely arranged in layers, but it has no blood vessels to nourish or protect it against infection. Instead, it receives its nourishment from the tears and the watery fluid (aqueous humor) that fills the chamber behind it.-->
What is dry eye?
Dry eye occurs when the eye does not produce tears properly, or when the tears are not of the correct consistency and evaporate too quickly.
In addition, inflammation of the surface of the eye may occur along with dry eye. If left untreated, this condition can lead to pain, ulcers, or scars on the cornea, and some loss of vision. However, permanent loss of vision from dry eye is uncommon.
Dry eye can make it more difficult to perform some activities, such as using a computer or reading for an extended period of time, and it can decrease tolerance for dry environments, such as the air inside an airplane.
What are tears, and how do they relate to dry eye?
Tears, made by the lacrimal gland, are necessary for overall eye health and clear vision. Tears bathe the surface of the eye, keeping it moist, and wash away dust and debris. They also help protect the eye from bacterial and other types of infections.
Tears are composed of three major components: a) outer, oily, lipid layer produced by the meibomian glands; b) middle, watery, lacrimal layer produced by the lacrimal glands; and c) inner, mucous or mucin layer produced by goblet cells located within a thin transparent layer over the white part of the eye and covering the inner surface of the eyelids. Tears are made of proteins (including growth factors), electrolytes, and vitamins that are critical to maintain the health of the eye surface and to prevent infection.
Tears are constantly produced to bathe, nourish, and protect the eye surface. They are also produced in response to emergencies, such as a particle of dust in the eye, an infection or irritation of the eye, or an onset of strong emotions. When the lacrimal glands fail to produce sufficient tears, dry eye can result.
Any disease process that alters the components of tears can make them unhealthy and result in dry eye.
What are the types of dry eye?
1) Aqueous tear-deficient dry eye is a disorder in which the lacrimal glands fail to produce enough of the watery component of tears to maintain a healthy eye surface.
2) Evaporative dry eye may result from inflammation of the meibomian glands, also located in the eyelids. These glands make the lipid or oily part of tears that slows evaporation and keeps the tears stable.
Dry eye can be associated with:
inflammation of the surface of the eye, the lacrimal gland, or the conjunctiva;
any disease process that alters the components of the tears;
an increase in the surface of the eye, as in thyroid disease when the eye protrudes forward;
cosmetic surgery, if the eyelids are opened too widely.
What are the symptoms of dry eye?
Dry eye symptoms may include any of the following:
stinging or burning of the eye;
a sandy or gritty feeling as if something is in the eye;
episodes of excess tears following very dry eye periods;
a stringy discharge from the eye;
pain and redness of the eye;
episodes of blurred vision;
heavy eyelids;
inability to cry when emotionally stressed;
uncomfortable contact lenses;
decreased tolerance of reading, working on the computer, or any activity that requires sustained visual attention;
eye fatigue.
NOTE: If symptoms of dry eye persist, consult an eye care professional to get an accurate diagnosis of the condition and begin treatment to avoid permanent damage.
Who is likely to develop dry eye?
Elderly people frequently experience dryness of the eyes, but dry eye can occur at any age. Nearly five million Americans 50 years of age and older are estimated to have dry eye. Of these, more than three million are women and more than one and a half million are men. Tens of millions more have less severe symptoms. Dry eye is more common after menopause. Women who experience menopause prematurely are more likely to have eye surface damage from dry eye.
What are the causes of dry eye?
Dry eye can be a temporary or chronic condition:
Dry eye can be a side effect of some medications, including antihistamines, nasal decongestants, tranquilizers, certain blood pressure medicines, Parkinson's medications, birth control pills and anti-depressants.
Skin disease on or around the eyelids can result in dry eye.
Diseases of the glands in the eyelids, such as meibomian gland dysfunction, can cause dry eye.
Dry eye can occur in women who are pregnant.
Women who are on hormone replacement therapy may experience dry eye symptoms. Women taking only estrogen are 70 percent more likely to experience dry eye, whereas those taking estrogen and progesterone have a 30 percent increased risk of developing dry eye.
Dry eye can also develop after the refractive surgery known as LASIK. These symptoms generally last three to six months, but may last longer in some cases.
Dry eye can result from chemical and thermal burns that scar the membrane lining the eyelids and covering the eye.
Allergies can be associated with dry eye.
Infrequent blinking, associated with staring at computer or video screens, may also lead to dry eye symptoms.
Both excessive and insufficient dosages of vitamins can contribute to dry eye.
Homeopathic remedies may have an adverse impact on a dry eye condition.
Loss of sensation in the cornea from long-term contact lens wear can lead to dry eye.
Dry eye can be associated with immune system disorders such as Sjögren's syndrome, lupus, and rheumatoid arthritis. Sjögren's leads to inflammation and dryness of the mouth, eyes, and other mucous membranes. It can also affect other organs, including the kidneys, lungs and blood vessels.
Dry eye can be a symptom of chronic inflammation of the conjunctiva, the membrane lining the eyelid and covering the front part of the eye, or the lacrimal gland. Chronic conjunctivitis can be caused by certain eye diseases, infection, exposure to irritants such as chemical fumes and tobacco smoke, or drafts from air conditioning or heating.
If the surface area of the eye is increased, as in thyroid disease when the eye protrudes forward or after cosmetic surgery if the eyelids are opened too widely, dry eye can result.
Dry eye may occur from exposure keratitis, in which the eyelids do not close completely during sleep.
What can I do to help myself?
Use artificial tears, gels, gel inserts, and ointments - available over the counter - as the first line of therapy. They offer temporary relief and provide an important replacement of naturally produced tears in patients with aqueous tear deficiency. Avoid artificial tears with preservatives if you need to apply them more than four times a day or preparations with chemicals that cause blood vessels to constrict.
Wearing glasses or sunglasses that fit close to the face (wrap around shades) or that have side shields can help slow tear evaporation from the eye surfaces. Indoors, an air cleaner to filter dust and other particles helps prevent dry eyes. A humidifier also may help by adding moisture to the air.
Avoid dry conditions and allow your eyes to rest when performing activities that require you to use your eyes for long periods of time. Instill lubricating eye drops while performing these tasks.
How is dry eye treated?
Depending on the causes of dry eye, your doctor may use various approaches to relieve the symptoms.
Dry eye can be managed as an ongoing condition. The first priority is to determine if a disease is the underlying cause of the dry eye (such as Sjögren's syndrome or lacrimal and meibomian gland dysfunction). If it is, then the underlying disease needs to be treated.
Cyclosporine, an anti-inflammatory medication, is the only prescription drug available to treat dry eye. It decreases corneal damage, increases basic tear production, and reduces symptoms of dry eye. It may take three to six months of twice-a-day dosages for the medication to work. In some cases of severe dry eye, short term use of corticosteroid eye drops that decrease inflammation is required.
If dry eye results from taking a medication, your doctor may recommend switching to a medication that does not cause the dry eye side effect.
If contact lens wear is the problem, your eye care practitioner may recommend another type of lens or reducing the number of hours you wear your lenses. In the case of severe dry eye, your eye care professional may advise you not to wear contact lenses at all.
Another option is to plug the drainage holes, small circular openings at the inner corners of the eyelids where tears drain from the eye into the nose. Lacrimal plugs, also called punctal plugs, can be inserted painlessly by an eye care professional. The patient usually does not feel them. These plugs are made of silicone or collagen, are reversible, and are a temporary measure. In severe cases, permanent plugs may be considered.
In some cases, a simple surgery, called punctal cautery, is recommended to permanently close the drainage holes. The procedure helps keep the limited volume of tears on the eye for a longer period of time.
In some patients with dry eye, supplements or dietary sources (such as tuna fish) of omega-3 fatty acids (especially DHA and EPA) may decrease symptoms of irritation. The use and dosage of nutritional supplements and vitamins should be discussed with your primary medical doctor
What is the cornea? The cornea is the clear, dome-shaped outer surface that covers the eye in front of the iris, the colored part of the eye. The cornea helps protect the rest of the eye from germs, dust, and other harmful matter. The cornea bends, or refracts, light entering the eye, and accounts for most of the eye's total focusing power. It also serves as a filter to screen out most of the damaging ultraviolet (UV) wavelengths in sunlight. The cornea is a highly organized, clear structure made up of a group of cells and proteins precisely arranged in layers, but it has no blood vessels to nourish or protect it against infection. Instead, it receives its nourishment from the tears and the watery fluid (aqueous humor) that fills the chamber behind it.--> What is dry eye? Dry eye occurs when the eye does not produce tears properly, or when the tears are not of the correct consistency and evaporate too quickly. In addition, inflammation of the surface of the eye may occur along with dry eye. If left untreated, this condition can lead to pain, ulcers, or scars on the cornea, and some loss of vision. However, permanent loss of vision from dry eye is uncommon. Dry eye can make it more difficult to perform some activities, such as using a computer or reading for an extended period of time, and it can decrease tolerance for dry environments, such as the air inside an airplane. What are tears, and how do they relate to dry eye? Tears, made by the lacrimal gland, are necessary for overall eye health and clear vision. Tears bathe the surface of the eye, keeping it moist, and wash away dust and debris. They also help protect the eye from bacterial and other types of infections. Tears are composed of three major components: a) outer, oily, lipid layer produced by the meibomian glands; b) middle, watery, lacrimal layer produced by the lacrimal glands; and c) inner, mucous or mucin layer produced by goblet cells located within a thin transparent layer over the white part of the eye and covering the inner surface of the eyelids. Tears are made of proteins (including growth factors), electrolytes, and vitamins that are critical to maintain the health of the eye surface and to prevent infection. Tears are constantly produced to bathe, nourish, and protect the eye surface. They are also produced in response to emergencies, such as a particle of dust in the eye, an infection or irritation of the eye, or an onset of strong emotions. When the lacrimal glands fail to produce sufficient tears, dry eye can result. Any disease process that alters the components of tears can make them unhealthy and result in dry eye. What are the types of dry eye? 1) Aqueous tear-deficient dry eye is a disorder in which the lacrimal glands fail to produce enough of the watery component of tears to maintain a healthy eye surface. 2) Evaporative dry eye may result from inflammation of the meibomian glands, also located in the eyelids. These glands make the lipid or oily part of tears that slows evaporation and keeps the tears stable. Dry eye can be associated with: inflammation of the surface of the eye, the lacrimal gland, or the conjunctiva; any disease process that alters the components of the tears; an increase in the surface of the eye, as in thyroid disease when the eye protrudes forward; cosmetic surgery, if the eyelids are opened too widely. What are the symptoms of dry eye? Dry eye symptoms may include any of the following: stinging or burning of the eye; a sandy or gritty feeling as if something is in the eye; episodes of excess tears following very dry eye periods; a stringy discharge from the eye; pain and redness of the eye; episodes of blurred vision; heavy eyelids; inability to cry when emotionally stressed; uncomfortable contact lenses; decreased tolerance of reading, working on the computer, or any activity that requires sustained visual attention; eye fatigue.
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