What is the Macula?

The macula is the name given to an area at the center of the retina (the back of the eye) rich in light-sensitive cells. This area is is responsible for central vision and allows you to see fine detail when performing tasks such as reading, writing or threading a needle.

What is Macular Degeneration?

Macular degeneration, also referred to as Age Related Macular Degeneration (AMD), is a condition that results in blurred and distorted central vision while peripheral vision is left unaffected. As AMD progresses, it can show up with dark spots or complete loss of central vision.

There are two types of Macular Degeneration: Dry AMD and Wet AMD.

Dry AMD

As someone ages, the layer of tissue under the retina starts to thicken. This prevents the proper exchange of nutrients into the cells and movement of waste products out of the cells. Over time, those waste products start to build up in the retina and create little deposits called drusen. With the accumulation of drusen and a decrease in nutrients reaching the cells, the macula becomes damaged and problems with central vision start to occur. Dry AMD progresses slowly over time, and many patients maintain their vision for many years after the process has started.

Wet AMD

In wet AMD, there is a growth of new, tiny blood vessels underneath the macula. While it is still unclear as to what exactly triggers the growth of these vessels, it is suggested that they are a way that the body attempts to clear waste products and move more nutrients to the retina.  Unfortunately, these blood vessels are poorly formed and fragile which causes them to leak blood and fluid into the retina. This results in scarring and damage to the macula and more rapid progression of central vision loss. Wet AMD often develops from Dry AMD.

What are the Symptoms of Macular Degeneration?

Comparison of the Amsler Grid as seen by someone without AMD (left) and someone with AMD (right).

Comparison of the Amsler Grid as seen by someone without AMD (left) and someone with AMD (right).

In the earlier stages, Macular Degeneration often shows no obvious signs. One of the first symptoms that a person may notice is blurred or distorted vision when performing detailed tasks like reading or writing, that is not corrected with prescription lenses. Eventually they may notice blurred central vision when looking at faces or watching TV. As the condition progresses, straight lines will start to look distorted or broken and dark spots may form in the central vision.

There is a common test to monitor for signs of macular degeneration called the Amsler Grid. In this test, a straight-line grid is used to notice any distortion in the central vision. As you can see to the right of the page, a person with healthy vision will see straight lines, while a person with macular degeneration will see distorted or broken lines that may be accompanied with a dark spot. It’s important to test one eye at a time because when both eyes are working together,  they may be correcting the distortion and hiding the vision problem.
(See Amsler Grid Test below to try it yourself).

In Macular Degeneration, once vision has been lost, it can not be fully restored, however early detection and intervention can effectively prevent further vision loss. Also note that the hallmark signs of Macular Degeneration may also show up in other conditions, so if you are experiencing any of the above symptoms or notice any abnormalities with the Amsler Grid test, it’s important to see your optometrist for a comprehensive eye exam.

Who is at risk for Macular Degeneration?

There are many potential risk factors for AMD. Some are factors that can’t be controlled such as age (50+), race and family history. There are other factors related to lifestyle such as smoking and unprotected exposure to UV light that increase the risk exponentially. Diet plays a big role in the development of AMD and the risk increases in those with low antioxidant intake, nutrient deficient diets and vitamin D deficiency. Obesity and cardiovascular disease also pose a big risk, particularly in the development of Wet AMD.

A scene as might be viewed by a person with Macular Degeneration.

A scene as might be viewed by a person with Macular Degeneration.

How can Macular Degeneration be prevented?

Simple ways to prevent macular degeneration include things like protecting the eyes with UV  blocking sunglasses, smoking cessation and receiving regular eye exams to catch early signs. One of the most effective ways to prevent AMD is through diet, with a particular focus on antioxidants like vitamins A, C and E and other nutrients such as omega-3 fatty acids, vitamin D, vitamin K and zinc. These can be found primarily in dark leafy greens, bright colored vegetables, fruits, berries, nuts and seeds. For those with more serious risks of AMD, ask your optometrist about supplementing with an AREDS formulation, an AMD specific formulation containing proven effective doses of each of these nutrients.

How is Macular Degeneration treated?

Dry macular degeneration is typically treated with an ocular vitamin supplement as mentioned above. Diet and lifestyle modifications will also be recommended including things like wearing sunglasses, stopping smoking, increasing exercise and evaluating diet to prevent further damage.

Wet macular degeneration may require more aggressive treatment including medications and/or other procedures recommended by your optometrist.

Early detection is crucial in terms of treating AMD, so regular eye exams are important for everyone. Once someone is diagnosed with Macular Degeneration, progression will be monitored closely by their care provider.

 

The Amsler Grid Test

amsler grid test

 

 

1. Wearing reading glasses if applicable, sit about 14 inches from the screen
2. Cover up your left eye and focus on the black dot in the center of the grid with your right eye
3. Without moving your right eye, notice if any of the lines are blurred, distorted or broken if there are any dark spots in your vision
4. Repeat with the left eye

If you notice any abnormalities with the Amsler Grid test, call our office to book an appointment with your optometrist.