Macular Degeneration 101

Frequently Asked Questions about Macular Degeneration

What is macular degeneration?

Pathologic condition (altered or caused by a disease or abnormal function) Group of conditions that include deterioration of the macula, resulting in loss of sharp central vision. Hereditary types can occur in any age group.

(Back to top.)

What is age related macular degeneration (AMD)?

Pathologic condition (altered or caused by a disease or abnormal function) Group of conditions that include deterioration of the macula, (small area at the back of the retina) resulting in a loss of sharp central vision. It is the leading cause of severe vision loss in people over age 60 in the western world. Vision loss occurs when the cells in the light sensitive region of the eye, known as the retina, start to deteriorate or break down. The most severely affected cells are those within a special region of the retina known as the macula, which is responsible for fine detail vision. This type of vision loss - central detail vision - affects reading, driving, watching TV, sewing, seeing the faces of family and friends, and any other task that requires focusing on small objects. Although macular degeneration reduces central vision, side vision remains clear. Sometimes only one eye loses vision while the other eye continues to see well.

There are two main types of macular degeneration: "dry" and "wet." Dry macular degeneration is the most common type of macular degeneration and vision loss is usually gradual. In fact, in its early stages, changes in vision may be hard to notice. One may realize that straight lines appear wavy, or that there are blank spots in the center of vision. Colors may look dim. There is no way to restore vision loss from dry AMD. However, dry macular degeneration must be monitored because it can turn into wet macular degeneration.

Wet macular degeneration results when abnormal blood vessels from underneath the retina leak blood or fluid thus causing that portion of the retina to bulge. This bulging of the retina distorts vision and is characterized by a sudden decrease in central vision. An eye with wet macular degeneration will usually lose its ability to see fine detail; although prompt treatment may slow or minimize vision loss. While only 10% of people with macular degeneration have the wet type, it accounts for about 90% of the cases that lead to severe vision loss.

(Back to top.)

How do I know if I have macular degeneration?

Your eye doctor can tell if you have macular degeneration - and its level of development - through an eye exam in which drops are placed in the eyes to dilate the pupils and a special lens is used to examine the retina. This procedure allows for careful examination of the inside of the eye. The ophthalmologist can give you a definitive diagnosis after this retinal examination.

(Back to top.)

What are the symptoms of macular degeneration?

In the early stages of macular degeneration, vision may seem blurred or somewhat distorted: or a blank spot may be seen in one's vision. Straight edges may seem bent or wavy. One may notice that each eye perceives the size or color of an object differently. Many people may not even notice early changes in vision because only one eye is affected while the other eye continues to see well. It is very important that any distortion of vision be promptly reported to an ophthalmologist for further evaluation.

Many older people develop macular degeneration as part of the natural aging process.

Drusen

Most people with drusen have no symptoms. However, the development of drusen may be a precursor to the development of macular degeneration. Drusen are deposits which lie beneath the retina in a layer called Bruch's membrane. Drusen can be a marker for macular degeneration (especially in the over 50 age group) because there appears to be an increased risk for macular degeneration as the number of drusen increases. Fat also accumulates in Bruch's membrane with age. This may also contribute to drusen formation. Drusen can be thought of as backed up waste products from various layers of the retina.

Are there different types of drusen?

Drusen occurs in two forms:

Persons with large, soft drusen may also be at risk for subretinal bleeding.

How is drusen treated?

There is no clinically effective way to treat drusen. However, several clinical trials are underway to evaluate various methods, including laser treatments, and their effects on drusen reduction, and on the progression of macular degeneration.

How is drusen managed?

It is very important to be followed closely by an ophthalmologist if drusen are present. Only an ophthalmologist can monitor subtle changes in the retina, and also manage any complications that may arise. Persons with drusen should also perform a self-test called an Amsler grid, on a routine basis to monitor for the presence of visual disorders.

(Back to top.)

What causes macular degeneration?

Besides age, and a family history of drusen, there are several characteristics that many people with macular degeneration seem to have in common. These include family history, smoking, or having blue or light colored eyes. Although seen as common factors in people with macular degeneration, it is not specifically known to what degree these characteristics actually increase one's risk for developing macular degeneration. There are also some animal studies that suggest exposure to Ultraviolet light can damage the retina causing drusen.

(Back to top.)

Is there a genetic link to age related macular degeneration?

There seems to be a genetic, hereditary link - many current studies related to this topic are being conducted. It seems that the risk for developing age related macular degeneration is higher if there are other family members who have it. It is not fully understood why this happens. If there is a gene that determines AMD and many family members have it, why doesn't each member develop the disease? Research is focused on identifying the gene or genes of AMD (and many have been isolated) and then determining why some people then get AMD and other family members do not.

(Back to top.)

Can macular degeneration be prevented?

The cause of macular degeneration is not clearly understood and thus, methods of prevention are unproven. Demographic studies examining people with macular degeneration and their common characteristics suggest that there may be ways to minimize one's risk for developing macular degeneration. These include cessation of smoking, wearing sunglasses to prevent exposure to ultraviolet light, the harmful radiation from the sun, and eating a diet containing antioxidants, lutein and zeaxanthin. Although studies examining these interventions have produced conflicting results with regard to preventing or minimizing macular degeneration, studies showing the general health value of stopping smoking and eating a diet rich in antioxidants are well supported.

(Back to top.)

How is macular degeneration treated?

Despite ongoing research, there is no cure or medical treatment for the dry form of macular degeneration. However, low vision rehabilitation is very useful in helping people use their remaining vision in order to perform activities of daily living and maintain as high a level of independence as possible.

Certain types of wet macular degeneration can be treated with laser therapy. Traditional laser therapy uses a highly focused light to dry up leaking blood vessels or preventing them from continuing to grow. The area, treated with the laser, becomes a permanent blind spot. However, the vision loss is usually less severe than if laser therapy was not done. Laser treatment does not permanently stop the formation of new blood vessels. Therefore, repeat treatments are usually needed.

The Food and Drug Administration approved a new treatment for wet macular degeneration, a treatment known as photodynamic therapy (PDT). PDT uses the medication Visudyne, that causes light sensitivity; and a low intensity laser. PDT may slow vision loss and in some cases, improve vision. Research suggests this treatment may be effective for 10 - 15% of people with wet form of macular degeneration. Unlike traditional laser therapy, PDT does not cause a blind spot on the retina.

Photdynamic Therapy (PDT)

Photodynamic therapy is considered effective for age related macular degeneration when vision loss results from blood vessels leaking under the center of the retina. A test known as fluorescein angiography can determine whether a particular person with AMD can be treated with PDT. About 10% - 15% of people with wet macular degeneration may benefit. However, research studies have documented no benefit to people who do not meet specific criteria. If you are interested in PDT for macular degeneration, talk with your ophthalmologist.

How can age related macular degeneration be managed?

There are three ways that macular degeneration can be managed:

Regular eye exams are very important to monitor the course of macular degeneration as well as to watch for other problems. In many cases, early detection of any new changes in vision or in the retina allow for earlier treatments and therefore, a better result.

It is very important that people with macular degeneration monitor their vision daily since sudden vision changes may be a sign of wet macular degeneration or new abnormal blood vessel growth or leaking. A simple test, called an Amsler grid, can reveal signs of macular degeneration such as blurry areas, wavy lines, or blank spots. Any changes should immediately be reported to the ophthalmologist.

Low vision aids can help with tasks that require detailed vision. It is also helpful to see a low vision specialist, a doctor specifically trained in low vision rehabilitation. Aids such as magnifiers, closed circuit television, reading machines, writing guides, large-faced appliances and clocks, large-print checks, and large print reading materials can help people continue to read and take care of themselves.

(Back to top.)

What is the impact of macular degeneration?

In personal terms, vision is the most important of the five senses: it links us most intimately to the world. Vision allows one to see a new grandchild, read a letter from a friend, scan a computer screen or navigate through traffic. At the beginning stage, macular degeneration, alone, does not result in complete loss of sight and most people continue to have some useful vision and are able to take care of themselves. As the disease advances, it is devastating, robbing people of their independence and their ability to function well in everyday life. Dreams and hopes of their later years vanish -- lives are not the same!

The Macula Vision Research Foundation is hopeful that its support of pioneering vision research will find the cause, prevention, treatment, and cure for macular degeneration.

(Back to top.)