Age-Related Macular Degeneration

Age-Related Macular Degeneration

Topic Overview

What is age-related macular degeneration?

Age-related macular degeneration is a disease that causes blurring of
your
central vision. The blurring happens because of damage
to the macula, a small area at the back of the
eye. The macula helps you see the fine detail in
things that your eyes are focusing on.

Macular degeneration makes
it harder to do things that require sharp central vision, like reading,
driving, and recognizing faces. It does not affect side vision, so it does not
lead to complete blindness.

There are two types of macular
degeneration—wet and dry. The dry form is by far the most common type. The wet
form is much less common, but it happens more quickly and is more
severe.

You may have either type in just one eye, but over time
you may get it in the other eye too.

What causes macular degeneration?

Macular
degeneration is the result of damage to the nerve cells in the
macula. The process that leads to this damage is
different for each type.

  • The dry form is a gradual process. As you
    age, the cells in the macula start to thin and break down, and waste deposits
    build up in the back of the eye. Over time, this damages the macula.
  • The wet form happens when abnormal blood vessels grow in the back
    of the eye. These blood vessels break easily and leak blood and fluid under the
    macula. This can quickly damage the macula and distort your central vision.

Experts are still studying the causes of both forms.

What are the symptoms?

The main symptom of macular
degeneration is dim or fuzzy central vision. Objects may look warped or smaller
than they really are. You may have a blank or blind spot in the center of your
field of vision. As the disease gets worse, you may have trouble with tasks
like reading and driving.

If you have the dry form, your vision will
probably become blurry slowly. You may have it for several years before it
affects your ability to read, drive, and do everyday activities.

Often the first symptom of the wet form is that straight
lines look wavy or curved. In the wet form, vision loss happens quickly and can be severe.

How is macular degeneration diagnosed?

A doctor
can usually detect macular degeneration by doing a regular eye exam and asking
questions about your past health. You may have some vision tests, including an
ophthalmoscopy. This test lets your doctor look at the inside of your eye and check for possible signs of this disease, such as drusen. These are yellowish white waste deposits that
can build up at the back of the eye.

How is it treated?

At this time, there is no cure
for macular degeneration. But experts are exploring many new treatments that
hold hope for the future. Your doctor can keep you up to date on any changes in
treatment that might help you.

Certain antioxidant vitamin and mineral supplements may help slow down vision loss in some people with
moderate to severe macular degeneration. Talk to your
doctor about whether this might help you.

Injections of medicine into your eye may slow down vision loss from the wet form of macular degeneration. Sometimes other treatments may be recommended.

How can you cope with vision problems?

There are
many things you can do at home to make the most of your remaining vision. Try using
aids like magnifying glasses, brighter lighting, and large-print books. Having a good support
network is important too.

If you need more help, your doctor may
refer you to an
occupational therapist or rehabilitation specialist.
These professionals can help you get the tools and training you need to cope
with reduced vision. Local agencies may also offer services for people who have
vision loss.

It can be scary to find out that you have a vision
problem that may get worse. It is common to have a range of emotions. But if
you feel very sad or hopeless, talk to your doctor.

Frequently Asked Questions

Learning about age-related macular degeneration (AMD):

Being diagnosed:

Getting treatment:

Living with AMD:

Health Tools

Health Tools help you make wise health decisions or take action to improve your health.


Actionsets are designed to help people take an active role in managing a health condition.

Cause

Vision loss from
age-related macular degeneration is caused by
damage to the light-detecting nerve cells in the
macula. The cause of this damage to the nerve cells is
unknown. A person's genes and family history may play a role.

Symptoms

Age-related macular degeneration (AMD) can cause these symptoms:

  • Central vision becomes dim, fuzzy, or less
    sharp.
  • Reading requires more light than it did in the
    past.
  • You find it harder to see people's faces
    clearly.
  • Objects appear distorted or smaller than they really
    are.
  • A new blank or blind spot develops in your central field of
    vision.
  • Straight lines begin to appear wavy or curved. This is
    usually the first symptom of wet AMD.
  • You have a loss of central
    vision that does not go away or becomes worse over time. The loss may be severe
    and rapid if you have wet AMD.

The symptoms of wet and dry AMD differ in two important
ways:

  • How fast the vision changes are
    • Dry AMD happens slowly. Vision changes
      may be so gradual that you don't notice them.
    • Wet AMD happens
      suddenly. Symptoms tend to appear suddenly and get worse
      fast.
  • How bad the vision changes are
    • Dry AMD symptoms are usually mild at first.
      Later, the symptoms can be more severe.
    • Wet AMD tends to cause
      more severe vision changes and vision loss.

What Happens

Dry AMD

With dry
age-related macular degeneration (dry AMD), the cells and blood vessels beneath the macula begin to thin and break down as they age.

When
these cells and blood vessels stop working, the nerve cells in the macula that
detect light can't work as well as they used to. As more and more of the nerve cells in
the macula break down, vision loss very slowly gets worse.

You
may have the disease for several years before it affects how you are able to read,
drive, and do everyday activities. If you have AMD in only one eye, you may not
notice minor vision changes, because your unaffected eye automatically makes up
for vision problems in your other eye.

A small percentage of people who have dry AMD eventually develop
wet AMD.

Wet AMD

Wet AMD begins with the growth of abnormal blood vessels under the macula. These blood vessels break easily. They
leak blood and fluid and cause scar tissue, all of which push against the
macula. They change the macula's shape and cause it to send distorted images to
your brain. Straight lines begin to appear wavy or curved, and objects may seem
oddly shaped or smaller.

Scar tissue also cuts off the macula
from the normal support cells that it needs in order to work. Nerve cells in
the macula begin to die, causing a loss of central vision.

If not treated, the scar beneath the macula may continue
to grow, affecting more and more of the nerve cells in the macula. Vision loss
gets worse as more of the macula becomes involved. The entire macula may be
destroyed by this process, resulting in a complete loss of central
vision.

Treatment can sometimes delay or prevent further vision
loss, but it cannot reverse vision loss that has already occurred.

With wet AMD,
vision loss can happen fast—within months or even weeks. This can make it hard to adjust to
the vision loss.

Even though AMD may affect
central vision, it doesn't cause complete blindness. And most people keep good side vision.

What Increases Your Risk

The main things that put you at risk (risk factors) for
age-related macular degeneration (AMD) include:

  • Age greater than 55. Older age is the biggest risk factor for getting AMD.
  • A family
    history
    of the disease. You are much more likely to get AMD if a close relative
    has it.
  • Race. Whites appear to have a higher risk than blacks or
    Hispanics.
  • Smoking. People who smoke are more likely to
    develop AMD than nonsmokers.

Other risk factors for developing AMD may include:footnote 1

  • Deposits at the back of the eye, called
    drusen. Eyes with large, soft drusen deposits are at a
    greater risk for developing abnormal blood vessels and wet AMD.
  • A
    diet high in saturated fat and cholesterol.
  • Not getting enough carotenoids, antioxidant vitamins, and zinc in your diet.

When To Call a Doctor

Call your doctor immediately if:

  • You have a sudden, rapid loss of
    vision.
  • You suddenly notice a new blank or dark spot in the center
    of your vision that does not go away.
  • Straight lines appear wavy or
    curved, or objects begin to change size or shape or appear distorted.

Your doctor will refer you to an eye doctor
(ophthalmologist) if needed.

Call your doctor to
discuss whether you need an eye exam if:

  • You
    see either of the following on an
    Amsler grid:

    • Lines that change or appear wavy and curved
    • A blank
      spot that you have not noticed before in the grid
  • You need more light to read than you used
    to.
  • Colors seem faded or less vivid than they used
    to.
  • Your vision seems to be getting more blurry.

Watchful waiting

Watchful waiting means to take a wait-and-see
approach.

Watchful waiting is not appropriate if you have rapid
vision loss or sudden changes in your vision. If you have any rapid vision
changes, go to your doctor as soon as possible. Immediate treatment may be able
to slow vision loss caused by wet AMD. Delaying treatment for wet AMD could
mean further loss of central vision.

If you have dry age-related macular degeneration (dry AMD),
watchful waiting is appropriate. You may
never develop vision loss to the point that it disrupts your regular
lifestyle.

Who to see

AMD can usually be
detected during a routine eye exam by your regular doctor or an eye care
professional (optometrist or
ophthalmologist).

An ophthalmologist who
specializes in problems with the retina and macula can diagnose which type of
AMD you have. Also, several treatments such as medicine injections for wet AMD are done
by an ophthalmologist.

To prepare for your appointment, see the topic Making the Most of Your Appointment.

Exams and Tests

A doctor can usually detect
age-related macular degeneration (AMD) with a regular
eye exam. The doctor first will find out more about your symptoms, past eye
problems, and other health conditions by asking you about your
medical history.

Vision tests

Visual acuity test

The doctor will
test your
central vision with a visual acuity test. During this
test, you cover one eye and read letters on a wall chart
20 ft (6.1 m) away. Central
vision gets worse over time in a person who has AMD, and a visual acuity test can
measure whether your vision has become worse since your last exam. The doctor
may also test your visual field, which includes both your central vision and
side (peripheral) vision.

Ophthalmoscopy

Your doctor will look inside your eye using ophthalmoscopy. This test lets your doctor check for possible signs of this disease, such as drusen, which appear as yellowish white spots under the
retina. Although some small drusen can usually be
found in the macula as a normal result of aging, the presence of numerous
large drusen is associated with AMD.footnote 1

Amsler grid test

An
Amsler grid test can detect
wet AMD. If you have wet AMD,
lines on the grid appear wavy or curved instead of straight, or
you may see a blank spot or hole on part of the grid.

For more
information on vision testing, see the topic
Vision Tests.

Other tests

If your doctor thinks that
you may have wet AMD, you may also have a test called an
eye angiogram or an optical coherence tomography (OCT) to find out if abnormal blood vessels
are growing beneath the macula. The tests can also locate leaky blood vessels
under the macula and help your doctor find out if they can be
treated.

If you have AMD and some loss of vision, your doctor may
do a
low-vision evaluation to help find ways for you to
make the most of your remaining vision and keep your quality of life.

Early detection

The American Academy of Ophthalmology recommends that all
people ages 40 to 54 have a comprehensive eye exam every 2 to
4 years to help detect AMD early. The following table summarizes the
recommendations for comprehensive eye exams:footnote 2

Eye exam schedule
Age (years) When to get a comprehensive eye exam
65 or olderEvery 1–2 years
55–64Every 1–3 years
40–54Every 2–4 years
Younger than 405–10 years

Treatment Overview

There is no cure for age-related macular degeneration (AMD), but certain treatments may delay vision loss.

Your doctor can refer you to counselors who
specialize in helping people adjust to living with low vision.

Dry AMD

Follow your doctor's advice for having
regular exams and for watching the condition at home (such as using an
Amsler grid), because dry AMD can sometimes develop into wet AMD.

Certain vitamin and mineral supplements may help slow vision loss. Studies show that antioxidant vitamin and mineral supplements can help delay the onset of advanced AMD or can help prevent further vision loss in people who have moderate AMD.footnote 1 Check with your doctor before
taking any supplements. Some can have harmful side effects, especially if you take high
doses.

Wet AMD

Treatment for wet AMD can sometimes slow down or delay further damage to your
central vision. But in most cases, growth of fragile
new blood vessels in wet AMD starts again. And even repeated treatment is usually not
effective over the long term in preventing some loss of central vision.

The main treatment for wet AMD is a medicine that is injected into your eye. This is called anti-VEGF medicine. Sometimes other treatments may be recommended, such as photodynamic therapy, which uses a light-sensitive medicine to block abnormal blood vessels beneath the macula.

Because wet AMD often causes rapid and severe loss of central vision, it
is important not to delay treatment if your doctor recommends it.

Prevention

You can't prevent
age-related macular degeneration (AMD). But there are
some steps you can take that may lower your risk of getting it.

  • Have regular eye exams. Eye exams may help
    you find out if you are at risk for AMD or, if you have AMD, may
    detect it early. Early detection can sometimes delay
    loss of vision.
  • Don't smoke. People who smoke are more
    likely to develop AMD than those who don't smoke.
    Even after you stop smoking, this increased risk may persist for many
    years.
  • Get regular exercise, and stay at a healthy weight. These choices may lower your risk of getting AMD.footnote 1

People who have an increased risk
for AMD should use the Amsler grid. Your doctor can give you one to use at home.

Home Treatment

There's no treatment that can cure age-related macular degeneration (AMD). But there are things you can do at home to care for your eyes.

Amsler grid

People with AMD should check the vision in both eyes using an
Amsler grid every day or as often as the doctor recommends. If any of the lines
on the grid change or begin to appear wavy and curved, or if you notice that
your vision is getting worse, call your doctor.

Living with reduced vision

Reduced vision or
vision loss from AMD can affect your life in many ways. How much it will affect
you depends on your lifestyle and on how bad your vision loss is. Work
with your doctor to find ways to make the best use of your remaining vision.
There are things that you can do to adjust and to keep your quality of
life as much as possible.

It is
normal to feel unhappy about your loss of vision. But if your feelings of sadness are
severe or do not improve, you may develop
depression, which requires treatment. If you need help
in dealing with your feelings about AMD, talk to your doctor and to your family
and friends. Your doctor can also refer you to a counselor who specializes in
helping people adjust to living with limited vision.

Medications

Anti-VEGF medicines, such as aflibercept (Eyelea), bevacizumab (Avastin) and ranibizumab (Lucentis), can slow the vision loss that is
linked to wet
age-related macular degeneration (wet AMD). In some people, these medicines may improve vision. These medicines are
injected into the eye.

Other Treatment

The main treatment for wet age-related macular degeneration (AMD) is injections of medicine into the eye. But in some cases doctors recommend other treatments, such as:

  • Laser surgery, which uses an intense beam of light to burn small areas of the retina
    and the abnormal blood vessels beneath the macula.
  • Photodynamic therapy, which uses a light-sensitive medicine to block abnormal blood vessels beneath the macula.

Studies are being done on possible other treatments for AMD. You can talk with your doctor about the progress of new potential treatments.

Other Places To Get Help

Organizations

American Academy of Ophthalmology: EyeSmart (U.S.)
www.geteyesmart.org

Library of Congress: National Library Service for the Blind and Physically Handicapped (U.S.)
www.loc.gov/nls/index.html

Macular Degeneration Partnership (U.S.)
www.amd.org

References

Citations

  1. American Academy of Ophthalmology Retina/Vitreous Panel (2015). Age-related macular degeneration. Preferred Practice Pattern Guidelines. San Francisco: American Academy of Ophthalmology. http://www.aao.org/preferred-practice-pattern/age-related-macular-degeneration-ppp-2015. Accessed April 30, 2015.
  2. American Academy of Ophthalmology (2010). Comprehensive Adult Medical Eye Evaluation (Preferred Practice Pattern). San Francisco: American Academy of Ophthalmology. Available online: http://one.aao.org/CE/PracticeGuidelines/PPP_Content.aspx?cid=64e9df91-dd10-4317-8142-6a87eee7f517.

Other Works Consulted

  • American Academy of Ophthalmology (2007). Vision Rehabilitation for Adults (Preferred Practice Pattern). San Francisco: American Academy of Ophthalmology. Available online: http://one.aao.org/CE/PracticeGuidelines/PPP.aspx.
  • Despriet DG, et al. (2006). Complement factor H polymorphism, complement activators, and risk of age-related macular degeneration. JAMA, 296(3): 301–309.
  • Fletcher EC, et al. (2011). Retina. In P Riordan-Eva, JP Whitcher, eds., Vaughan and Asbury's General Ophthalmology, 18th ed., pp. 190–221. New York: McGraw-Hill.
  • Vedula SS, Krzystolik M (2008). Antiangiogenic therapy with anti-vascular endothelial growth factor modalities for neovascular age-related macular degeneration. Cochrane Database of Systematic Reviews (2).

Credits

ByHealthwise StaffPrimary Medical Reviewer Kathleen Romito, MD - Family Medicine Adam Husney, MD - Family Medicine E. Gregory Thompson, MD - Internal Medicine Specialist Medical Reviewer Christopher J. Rudnisky, MD, MPH, FRCSC - Ophthalmology

Current as ofFebruary 27, 2018

Do NOT follow this link or you will be banned from the site!