|
Home
Contacts
Acuvue Contact Lenses
Freshlook Contacts
Focus Daily
Discount Contacts
Bifocals
Toric
Color Contacts
Manufacturers
Bausch and Lomb
Ciba Vision
Coopervision
Accessories
Contact Lens Cases
Contact Lens
Solutions
Vision
Eye
Exams
Computer Vision
Sports Vision
Vision and Nutrition
Contact
Lens Prescriptions
LASIK & Vision
Surgery
Eye Illnesses
Astigmatism
Macular
Degeneration
Myopia
Presbyopia
Hyperopia
Cataracts
Diabetic
Retinopathy
Glaucoma
Retinal Detachment
|
Macular Degeneration
Macular degeneration is the leading cause of vision loss in individuals
over the age of 50. It develops with age, and is also called age-related
macular degeneration.
What is Macular Degeneration?
Macular Degeneration is a chronic eye disease. It results from the
deterioration of tissue in the macula. The macula is an area of the retina
that is responsible for central vision. Macular degeneration affects
central vision as opposed to peripheral vision. For this reason, it does
not cause complete vision loss. It can, however, cause severe vision loss
and although it can't be cured or reversed, early detection is critical
for effective treatment.
Clear central vision is necessary for many tasks, such as reading, facial
recognition and driving. The first symptom of macular degeneration is
typically the need for more light when reading. Images appear distorted or
bent, and the center of the visual field may be impeded by blank spots or
dark spots. Macular degeneration can progress rapidly, making early
detection that much more important.
The retina is a layer of tissue that sits on the back wall of the eyeball.
At the center of the retina lies the macula, which holds rods and cones -
light sensitive cells that are essential for central vision. The
underlying layer of blood vessels responsible for providing nourishment to
rods and cones is called the choroid. On the outermost surface of the
retina lies the retinal pigment epithelium (RPE), a layer of tissue that
provides a passage for nutrients from the choroid to the retina.
As eyes age, the RPE deteriorates and gets thinner. This negatively
impacts the movement of nutrients and leads to the formation of waste
deposits. The end result is damage to the rods and cones present in the
macula, causing blurred or distorted vision.
There are two types of Macular Degeneration
1) Dry Macular Degeneration
This is the most commmon form of macular degeneration. Typically, dry
macular degeneration affects both eyes, but often begins in one eye. Dry
macular degeneration involves the RPE cells, and severely interrupts the
normal disposal of waste, causing waste to build up in the RPE and the
degeneration of cells in the macula. Dry macular degeneration is brought
on by aging, and can result in complete loss of central vision
2) Wet Macular Degeneration
Wet macular degeneration begins with dry macular degeneration, and
accounts for up to 15% of all cases of macular degeneration. Cases of wet
macular degeneration cause close to 90% of all cases of severe vision loss
from either type of macular degeneration.
This form of macular degeneration results from the growth of new blood
vessels from the choroid that leak blood or fluid, causing the
deterioration of central vision. It is believed that the abnormal growth
of blood vessels may be caused by an interruption in the waste disposal
system from the cones and rods and the subsequent accumulation of
nutrients to the macula.
Wet macular degeneration typically leads to severe and rapid vision loss.
Both types of macular degeneration carry with them their own symptoms.
Dry Macular Degeneration
- Requiring very bright light when reading or doing close detail work
- Finding that printed words appear blurry
- Washed out or dull color perception
- Blind spots in the center of the visual field
- Increased overall blurriness of vision
Wet Macular Degeneration
- Visual distortions
- Blurry spot in central vision
- Decreased central vision
In both forms of macular degeneration, a patient may feel symptoms
occurring in only one eye; however, as the condition develops in the other
eye, the good eye is able to compensate less for the limitations of the
initially affected eye, and overall eyesight is significantly diminished.
Are you at risk?
Although researchers have yet to pinpoint the actual cause of macular
degeneration, they do believe that some factors may contribute to a
person's susceptibility.
1) Age
Individuals over age 50 are at much higher risk.
2) Sex
Women are more likely than men to be affected by macular degeneration.
3) Race
Asian Americans, American blacks and American Indians are less likely than
other groups to develop macular degeneration.
4) Ultraviolet Light Exposure
Long term exposure to intense sunlight and sunlamps can increase the
chances of developing macular degeneration.
5) Eye Color
Individuals with light colored eyes are most likely to develop the
disease.
6) Nutrients
Low levels of minerals and vitamins such as A, C, and E may increase the
risk of developing the disease.
7) Cardiovascular Disease
Patients who have experienced heart attack, stroke, angina or circulatory
problems may be at increased risk.
8) Smoking
Smokers are up to 3 times as likely as non-smokers to develop macular
degeneration.
Diagnosing Macular Degeneration
When a doctor conducts a complete
eye exam, he or she will examine the
macula. The presence of mottled pigmentation in the macula is a sign of
macular degeneration. A comprehensive eye exam will include an examination
for central vision, typically using an Amsler grid. A doctor can determine
the extent to which macular damage is present by examining where on the
grid visual distortion occurs.
Fluorescein Angiography can be used to assess the extent of damage from
macular degeneration. Fluorescent dye is injected into a leg or arm and
photographs are taken as the dye passes through the blood vessels in the
retina and choroid. This test shows the presence of abnormal blood vessels
in the macula and detects changes in macular pigmentation.
The damage caused by macular degeneration cannot be reversed; however, as
with so many other eye diseases, early prevention and treatment are
critical.
Resources: Get detailed information from the
Macular Degeneration Foundation. Learn about
treatment options for macular degeneration.
|
