Age-related Macular Degeneration (AMD), the leading cause of legal blindness in people 65 years or older in the United
States affects more than 10 million Americans according to the National Eye Institute.  

People with AMD may have difficulty with daily tasks that require fine vision such as reading and dialing a telephone.  
However, AMD does not damage the side vision, which is what one needs to get around without bumping into
furniture or other objects.  

What is Macular Degeneration?

The retina is the nerve layer in your eyes that perceives light, which is transmitted to the brain so that we can see.  In
many ways it is like film in a camera.  At the center of the retina is the macula, which allows you to see straight ahead
(your central vision).
There are two forms of macular degeneration, dry and wet.  

The dry type is more common, slow in progression and,
initially, less serious.  The initial stages of dry AMD presents
as yellowish spots called Drusen.  These spots can coalesce
to form larger areas.  The atrophy of the overlying retina
causes the vision loss seen in dry AMD.
Recently, selected vitamins have been shown to delay
progression in patients with early dry AMD.  
Commonly called the AREDS vitamins, these specially
formulated multivitamin tablets are highly recommend
for patients with mild to moderate dry AMD.  People who are current smokers or have quit recently should get the
non smokers formula to avoid certain side effects of high dose vitamin A (Beta Carotene).


The wet form is the second and more serious type of the disease.  In this case, abnormal blood vessels sprout in areas
of drusen and atrophy. These blood vessels can break and bleed very easily leading to hemorrhage and scarring
causing severe and rapid vision loss.











What causes AMD?

In dry macular degeneration vision loss is caused by atrophy (wasting away) of retinal tissue.  In the wet form vision
loss is usually caused by the growth of abnormal blood vessels that leak fluid and blood under the macular area of the
retina.

Who may be at risk for getting AMD?

Risk Factors for AMD include:
-        Family history of AMD (parents, brothers and sisters with the disease)
-        Smoking
-        High blood pressure and high cholesterol levels
-        Obesity

What are the AMD Symptoms?

-        Distorted vision
-        Blurry vision
-        Changes in color vision
-        Sudden Vision loss


How do you monitor progression of AMD?
Any change in vision in a patient with known AMD should be immediately reported to your Retina Specialist.  Patients
can use an Amsler grid to monitor their central vision.  Appearance of any new areas of distortion or any new gray
spots or blind spots might mean that the AMD is getting worse and should be reported to your retina doctor.  



















Instruction for Amsler Grid Use:

1) Cover one eye.

2) Look at the center dot and keep your eye focused on it at all times.

3) While looking directly at the center, and only the center, be sure that all the lines are straight and all the small   
squares are the same size.

4) Wear your reading glasses.

5) If you should notice any area on the grid that becomes distorted, blurred, discolored, or otherwise abnormal, please
call right away.

6) Do this test for each eye separately.


What can be done to treat AMD?

At present, there is no treatment available for dry AMD.  Studies done have shown that combination of certain
vitamins can reduce the risk of progression of dry AMD to the Wet kind.  Popularly known as the AREDS vitamins,
these readily available formulations contain Vitamin A (Beta Carotene), Vitamin C, Vitamin E, Copper and Zinc.  There
may be certain additional added nutrients like calcium and lutein.  These vitamins when taken regularly can reduce the
rate of progression to the wet AMD.  
Smokers need to take the Non-smokers formulation which lacks Vitamin A.  High doses of Vitamin A in Beta Carotene
form were linked to increased risk of developing lung cancer in people with smoking history.

Additional information about these vitamins can be obtained in the Academy Information Sheet

In case of wet AMD, there are several treatment options available.  All these treatments are meant to halt the
progression of AMD and prevent worsening of vision.  


The treatment regimen for Wet AMD is undergoing major changes.  Till recent past, the only treatments available
were heat laser or Visudyne Laser.  Both these methods were aimed at creating scarring of the abnormal blood vessels
to prevent further vision loss.  
Some of the newer medications available are aimed at a chemical called Vascular endothelial growth factor or VEGF
for short.  VEGF is a naturally occurring chemical in the body that is vital to many of our normal body functions.  
However in certain conditions, VEGF can cause abnormal blood vessel growth.  The newer medications available are
aimed at stopping this growth by blocking the action of VEGF.

The first Anti-VEGF medication that became available for treatment of AMD is called Macugen.  This medication
when given in form of injections into the eye was effective but improved vision in only about 6% of patients.

Another medication that is been used extensively is called Avastin.  This medication was developed by Genentech for
treatment of patients with colon cancer.  This medication when given as injection in the eye has been shown to reduce
the progression of AMD in a significant number of patient and even improve vision in numerous patients.  This
medication however has not been approved by FDA for treatment of macular degeneration.  When used in patients
with colon cancer in doses of 400 mg given once a month through intravenous route, these patients experienced side
effects that included bowel perforations, hemorrhage, strokes, high blood pressure and congestive heart failure.  In
case of usage in the AMD patients, the dose of medication used is only 1.25mg.  While the significantly lower dose of
Avastin when given into the eye directly reduces the risk of these potential complications, no FDA approved study has
been done to evaluate the true risk profile in this scenario.  You should talk to your doctor for additional information
about this medication.

The latest medication on the market is LUCENTIS which was also developed by Genentech specifically for the AMD
treatment. This medication also works in a manner similar to Avastin and has a similar risk profile.  

All three of these medications need to be injected directly into the eye and must given at periodic intervals varying
from 4 to 6 weeks.  Your retina specialist will do tests like fluorescein angiography to determine  the need for
continuing treatments.

For additional  information about AMD, please contact our office.

Additional Links:

American Academy of Ophthalmology Fact Sheet about AMD