WHAT YOU SHOULD KNOW ABOUT AGE- RELATED MACULAR DEGENERATION
Christiane Tourtet B.A.
November 01, 2007
Age-related macular degeneration (AMD) as the name implies, is an eye disease associated with the aging process that destroys gradually sharp central vision.
Central vision is essential to be able to see objects clearly and to perform common tasks such as driving and reading .Age-related macular degeneration which is not painful, affects the macula, which is the part of the eye that permit you to see fine details.
Sometimes AMD progresses so slowly that people notice very little change in their vision. However, in other cases, the disease progresses quite faster and may lead to a loss of vision in both eyes. For people 60 years and older, AMD is a leading cause of vision loss. AMD can occur in two forms, wet and dry. When abnormal blood vessels behind the retina start to grow under the macula, wet AMD occurs. The location of the macula is in the center of the retina, the light-sensitive tissue found at the back of the eye. The retina immediately converts an image or light into electrical impulses. The retina then sends to the nerves, signals or impulses to the brain.
The new blood vessels have a tendency to be very fragile and quite often leak fluid and blood. Loss of central vision can occur quickly with wet AMD. Wet AMD is also called advanced AMD, but it does not have stages like in dry AMD.
One of the early symptoms of wet AMD is that lines that are straight appear wavy. If you experience this type of symptom, contact your eye care professional immediately for a comprehensive dilated eye exam. When the light –sensitive cells in the macula slowly break down, dry AMD occurs, and gradually blurs the central vision in the affected area.
As dry AMD worsens, you may see spots that are blurred in the center of your vision. As the macula decreases in functions, over time, there is a gradually loss of central vision in the affected eye. One of the most common symptoms of dry AMD is a slightly blurred vision. In this instance you may need more light for performing tasks such as reading, and you may have difficulty recognizing faces. Usually dry AMD affects both eyes, but vision can be lost in one eye only, while the other eye appears to be unaffected.
Drusen are one of the most common early signs of dry AMD. Drusen are deposits that are yellow, and located under the retina. They usually are found in people over age 60 and can be detected during a comprehensive dilated eye exam. However drusen
usually do not cause loss of vision. Scientists are not sure about the connection between AMD and drusen, but they do know that a person´s risk of developing either wet AMD or dry AMD is due to an increase in the number or size of drusen. Serious vision loss can occur due to these changes.
There are three stages in dry AMD, all of which might occur in both eyes or in one eye.
Early AMD: People who have early AMD have either few medium-sized drusen or several small drusen. There is no vision loss or symptoms at this stage.
Intermediate AMD: People who have intermediate AMD have either one or more large drusen or many medium-sized drusen. Much more light may be needed for reading, and for many other tasks. Some persons see in the center of their vision a blurred spot.
Advanced Dry AMD People who have advanced dry AMD have a breakdown of supporting tissue in the central retinal and of light-sensitive cells. This breakdown can be responsible for a blurred spot in the center of your vision. Overtime, this blurred spot may get darker and bigger, taking more of central vision. It may be then difficult to read or to recognize faces unless they are very close to you. If there is loss of vision from dry AMD in one eye only, you may not notice in your overall vision any changes. You will still be able to read, see fine details, drive, since the other eye is seeing clearly. If AMD affects both eyes, then you will notice changes in your vision, and if blurriness occurs, see as soon as possible an eye care professional for a comprehensive dilated eye exam.
Ninety percent of all the people who have AMD have this type, and scientists are still uncertain as to what causes dry AMD.
The dry form of AMD is the most common one, and over 85 percent of all people who have intermediate and advanced AMD have the dry form. But, if only advanced is considered, then, about two-thirds of patients have the wet form. Almost all loss of vision comes from advanced AMD, and the wet forms leads to much more loss of vision than the dry form. The dry form can turn into the wet form, and all the people who have the wet form had the dry form first.
The dry form can progress and cause loss of vision without turning into the wet form, but it can also suddenly turn into the wet form even during the early stage of AMD. There is no way of knowing when will the dry form turn into the wet form. The wet form does not have early and intermediate stages. It is considered advanced AMD, right away.
The advanced AMD can be both dry form and wet form, and loss of vision can occur with either form, but in most cases, only advanced AMD can cause loss of vision. People who have advanced AMD in one eye only, are at a very high risk of developing advanced AMD in the other eye.
The age factor is the greatest risk. Even though AMD can occur during middle age, studies show that people that are over age 60 are at a much greater risk than people in other age groups. For example, a quite large study found that people in middle-age have approximately a 2 percent risk of getting AMD, but the risk of getting AMD increased to almost 30 percent in people over age 75. There are other risks factors as well, such as smoking, race, obesity, gender, family history. Women appear to be at a greater risk than men, and those with immediate members of their family who have AMD are at a higher risk of developing AMD.
Your lifestyle can make a difference in reducing your risk of developing AMD. It is important to eat a good, healthy diet, high in vegetables, fish, and especially green leafy vegetables. Do not smoke, do exercise, watch your weight, and maintain normal blood pressure.
Dry and wet AMD cause no pain at all. If you are over age 60, and you have experienced recent changes in your central vision, your eye care professional may suspect AMD. Advanced macular degeneration can be detected during a comprehensive eye exam that includes visual acuity test, dilated eye exam and tonometry. Other tests may also be done to learn more about the structure and the health of your eye.
Wet AMD can be treated with photodynamic therapy, which is relatively painless, and takes about 20 minutes in a doctor´s office, laser surgery which can be performed in a doctor´s office or eye clinic, and injections in the eye, that can be given as often as monthly in a doctor´s office, and can help slow down loss of vision from AMD and sometimes, in some cases improve eyesight. It is important to know that after laser treatment the risk of developing new blood vessels is high.
None of these treatments is a cure for wet AMD. The disease and vision loss may progress despite repeated treatments. No form of treatment can prevent loss of vision once dry AMD reaches the advanced stage, treatment can possibly prevent or delay intermediate AMD from progressing to the advanced stage.
According to the National Eye Institute´s Age-Related Eye Disease Study (AREDS) taking a specific high-dose formulation of antioxidants and zinc reduces significantly the risk of advanced AMD and its associated loss of vision. The vision of many people can be saved by slowing the progression of AMD from the intermediate stage to the advanced stage. Consult with your doctor, if you would like to take the specific high-dose formulation of antioxidants and zinc, used by the researchers of the AREDS.
If some loss of vision has already occurred from AMD, you can still use your eyes for routine activities, reading, watching TV, as normal use of your eyes is not going to create further damage to your vision. You can ask your eye care professional about low vision devices and services. The National Eyes Institute is supporting and conducting numerous studies to learn more about AMD, such as studying the possibility of transplanting healthy cells into a diseased retina, looking into certain anti-inflammatory treatments for the wet form of AMD, doing an evaluation of families with an history of AMD to be able to understand hereditary and genetic factors that may cause the disease. This research is quite helpful as it should provide better ways to detect, prevent, and treat loss of vision in people with AMD.
Resource:
National Eye Institute, U.S. National Institutes of Health.
© 2007 Christiane Tourtet, all rights reserved.
Central vision is essential to be able to see objects clearly and to perform common tasks such as driving and reading .Age-related macular degeneration which is not painful, affects the macula, which is the part of the eye that permit you to see fine details.
Sometimes AMD progresses so slowly that people notice very little change in their vision. However, in other cases, the disease progresses quite faster and may lead to a loss of vision in both eyes. For people 60 years and older, AMD is a leading cause of vision loss. AMD can occur in two forms, wet and dry. When abnormal blood vessels behind the retina start to grow under the macula, wet AMD occurs. The location of the macula is in the center of the retina, the light-sensitive tissue found at the back of the eye. The retina immediately converts an image or light into electrical impulses. The retina then sends to the nerves, signals or impulses to the brain.
The new blood vessels have a tendency to be very fragile and quite often leak fluid and blood. Loss of central vision can occur quickly with wet AMD. Wet AMD is also called advanced AMD, but it does not have stages like in dry AMD.
One of the early symptoms of wet AMD is that lines that are straight appear wavy. If you experience this type of symptom, contact your eye care professional immediately for a comprehensive dilated eye exam. When the light –sensitive cells in the macula slowly break down, dry AMD occurs, and gradually blurs the central vision in the affected area.
As dry AMD worsens, you may see spots that are blurred in the center of your vision. As the macula decreases in functions, over time, there is a gradually loss of central vision in the affected eye. One of the most common symptoms of dry AMD is a slightly blurred vision. In this instance you may need more light for performing tasks such as reading, and you may have difficulty recognizing faces. Usually dry AMD affects both eyes, but vision can be lost in one eye only, while the other eye appears to be unaffected.
Drusen are one of the most common early signs of dry AMD. Drusen are deposits that are yellow, and located under the retina. They usually are found in people over age 60 and can be detected during a comprehensive dilated eye exam. However drusen
usually do not cause loss of vision. Scientists are not sure about the connection between AMD and drusen, but they do know that a person´s risk of developing either wet AMD or dry AMD is due to an increase in the number or size of drusen. Serious vision loss can occur due to these changes.
There are three stages in dry AMD, all of which might occur in both eyes or in one eye.
Early AMD: People who have early AMD have either few medium-sized drusen or several small drusen. There is no vision loss or symptoms at this stage.
Intermediate AMD: People who have intermediate AMD have either one or more large drusen or many medium-sized drusen. Much more light may be needed for reading, and for many other tasks. Some persons see in the center of their vision a blurred spot.
Advanced Dry AMD People who have advanced dry AMD have a breakdown of supporting tissue in the central retinal and of light-sensitive cells. This breakdown can be responsible for a blurred spot in the center of your vision. Overtime, this blurred spot may get darker and bigger, taking more of central vision. It may be then difficult to read or to recognize faces unless they are very close to you. If there is loss of vision from dry AMD in one eye only, you may not notice in your overall vision any changes. You will still be able to read, see fine details, drive, since the other eye is seeing clearly. If AMD affects both eyes, then you will notice changes in your vision, and if blurriness occurs, see as soon as possible an eye care professional for a comprehensive dilated eye exam.
Ninety percent of all the people who have AMD have this type, and scientists are still uncertain as to what causes dry AMD.
The dry form of AMD is the most common one, and over 85 percent of all people who have intermediate and advanced AMD have the dry form. But, if only advanced is considered, then, about two-thirds of patients have the wet form. Almost all loss of vision comes from advanced AMD, and the wet forms leads to much more loss of vision than the dry form. The dry form can turn into the wet form, and all the people who have the wet form had the dry form first.
The dry form can progress and cause loss of vision without turning into the wet form, but it can also suddenly turn into the wet form even during the early stage of AMD. There is no way of knowing when will the dry form turn into the wet form. The wet form does not have early and intermediate stages. It is considered advanced AMD, right away.
The advanced AMD can be both dry form and wet form, and loss of vision can occur with either form, but in most cases, only advanced AMD can cause loss of vision. People who have advanced AMD in one eye only, are at a very high risk of developing advanced AMD in the other eye.
The age factor is the greatest risk. Even though AMD can occur during middle age, studies show that people that are over age 60 are at a much greater risk than people in other age groups. For example, a quite large study found that people in middle-age have approximately a 2 percent risk of getting AMD, but the risk of getting AMD increased to almost 30 percent in people over age 75. There are other risks factors as well, such as smoking, race, obesity, gender, family history. Women appear to be at a greater risk than men, and those with immediate members of their family who have AMD are at a higher risk of developing AMD.
Your lifestyle can make a difference in reducing your risk of developing AMD. It is important to eat a good, healthy diet, high in vegetables, fish, and especially green leafy vegetables. Do not smoke, do exercise, watch your weight, and maintain normal blood pressure.
Dry and wet AMD cause no pain at all. If you are over age 60, and you have experienced recent changes in your central vision, your eye care professional may suspect AMD. Advanced macular degeneration can be detected during a comprehensive eye exam that includes visual acuity test, dilated eye exam and tonometry. Other tests may also be done to learn more about the structure and the health of your eye.
Wet AMD can be treated with photodynamic therapy, which is relatively painless, and takes about 20 minutes in a doctor´s office, laser surgery which can be performed in a doctor´s office or eye clinic, and injections in the eye, that can be given as often as monthly in a doctor´s office, and can help slow down loss of vision from AMD and sometimes, in some cases improve eyesight. It is important to know that after laser treatment the risk of developing new blood vessels is high.
None of these treatments is a cure for wet AMD. The disease and vision loss may progress despite repeated treatments. No form of treatment can prevent loss of vision once dry AMD reaches the advanced stage, treatment can possibly prevent or delay intermediate AMD from progressing to the advanced stage.
According to the National Eye Institute´s Age-Related Eye Disease Study (AREDS) taking a specific high-dose formulation of antioxidants and zinc reduces significantly the risk of advanced AMD and its associated loss of vision. The vision of many people can be saved by slowing the progression of AMD from the intermediate stage to the advanced stage. Consult with your doctor, if you would like to take the specific high-dose formulation of antioxidants and zinc, used by the researchers of the AREDS.
If some loss of vision has already occurred from AMD, you can still use your eyes for routine activities, reading, watching TV, as normal use of your eyes is not going to create further damage to your vision. You can ask your eye care professional about low vision devices and services. The National Eyes Institute is supporting and conducting numerous studies to learn more about AMD, such as studying the possibility of transplanting healthy cells into a diseased retina, looking into certain anti-inflammatory treatments for the wet form of AMD, doing an evaluation of families with an history of AMD to be able to understand hereditary and genetic factors that may cause the disease. This research is quite helpful as it should provide better ways to detect, prevent, and treat loss of vision in people with AMD.
Resource:
National Eye Institute, U.S. National Institutes of Health.
© 2007 Christiane Tourtet, all rights reserved.
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