Macular Degeneration: What it is, how to detect it with a simple at-home test, and how to prevent it

Macular degeneration is a vexing eye condition that is 2^nd only to cataracts as a robber of good sight. Currently it affects more than 10 million Americans and is the leading cause of legal blindness in persons over the age of 55. While MD does not result in complete blindness in most sufferers, it does frequently interfere with reading, driving, and performing other daily activities.

What is MD?

Macular Degeneration refers to the degeneration of the central part or macula of the retina in the human eye. There are two forms of MD: One results from an overgrowth of blood vessels in the retina and is called the wet type. It is somewhat rare. The other is the “dry type” which accounts for 90% of all MD cases.  

The macula itself is made up of densely packed light-sensitive cells called rods and cones. These cells, particularly the cones, are essential for central vision. The cones make possible color vision, while the rods enable us to see shades of gray. There is also a layer of blood vessels called the choroid that underlies the retina and which nourishes the cones and rods of the retina, as well as a layer forming the outermost surface of the retina called the retinal pigment epithelium (RPE). The RPE is crucial to the flow of nutrients from the choroid to the retina and also helps shuttle waste products from the retina to the choroid.

As we grow older, the RPE can deteriorate, lose its pigment and become atrophied. This has been linked to many things including smoking, arterial blockage, free radical damage due to a lack of dietary antioxidant intake, and such. This disrupts the nutritional influx and waste-removal between the retina and choroid. Waste deposits, especially a form of age-related extracellular accumulations called Drusen begin to form. Damaged cells can no longer send normal signals through the optic nerve to the brain, and as a result vision becomes blurred.

Initially, sufferers may notice little or no change in their vision. But as the drusen continues to develop, vision may deteriorate.

Thankfully, there is a way that you can test your vision at home to see if you might be developing MD called the Amsler Grid.

Click here to print out your own Amsler Grid. Tape the grip onto a wall or mirror, stand back about 14 inches, and with one eye covered look at the grid. 

• Are you able to see the corners and sides of the grid?
• Do you see any wavy lines?
• Are there any holes or missing areas in the grid?

Now do the same test using the other eye.

If the lines of grid do not appear straight and parallel or there are missing areas (either or both eyes), make an appointment to see your eye doctor right away.

Get your eyes examined. The early detection of macular degeneration increases your odds of preventing serious vision loss. If you are 40 years of age or older, get an exam every two to four years, and if you’re older than 65, have an exam every year or two.

Wear sunglasses that filter out harmful ultraviolet light. Orange-, yellow- or amber-tinted lenses can filter out retinal cell damaging ultraviolet light and blue light. Look for glasses that filter 99 percent to 100 percent of ultraviolet A (UVA) and ultraviolet B (UVB) rays.

Stop smoking. Smokers are more likely to develop macular degeneration than nonsmokers. Your doctor can suggest drugs and nicotine withdrawal approaches of merit.

Eat fish or take fish oil softgels. According to a study published in April 2006, a diet rich in fish and the omega-3 fatty acids found in fish (supplements) can help reduce the risk of developing macular degeneration. Diabetics and those on blood thinners should check with their primary care doctors concerning taking fish oil supplements. Those who wish to consume more fish should select species that typically sport the lowest levels of mercury (Farm raised fish frequently have higher levels than wild caught fish!)

Keep a handle on diseases that complicate or contribute to MD. If you have cardiovascular disease or high blood pressure, take your prescribed medication(s) and follow your doctor's instructions for managing your condition. Persons battling high cholesterol or existing heart disease might want to take a look at HEARTROL and CARDIUM, while those who have elevated homocysteine should read up on NUTRACENE. 

Combat Free Radicals, Reduce lipofushin & AGEs (Age-related glycation end products)

A diet rich in vegetables and fruits will supply a wealth of antioxidants. This intake, however, may not be sufficient to cover all the bases. People with certain health conditions such as type II diabetes churn out cell damaging free radicals at rates that may exceed the ability of native antioxidant defenses to keep pace. For these folks and others who might be “antioxidant challenged”, there are many ways to shore up these defenses. Among these: Full spectrum antioxidant supplements. But, that’s pills or tablets, right?! Not necessarily. There are many tasty antioxidant rich powder blends on the market these days, many of which are created using vegetable and fruit extracts. In addition, there is a chewing gum that provides users with a form of the antioxidant glutathione which resists breakdown until it has reached tissues everywhere in the body: Th-Queen™    

Lutein and zeaxanthin may also be of value in both preventing and treating MD. These are are free radical neutralizing carotenoids found in corn and dark green leafy vegetables, which also abound in high concentrations in the eye. Some researchers feel that lutein and zeaxanthin may protect the macula from light-induced damage by essentially dyeing it yellow (which constitutes a kind of natural sun filtration mechanism not unlike yellow lens sunglasses). 

The potential of lutein and zeaxathin for MD prevention and treatment was underscored in a 12 month double-blind, placebo-controlled study involving 90 people with dry macular degeneration. The participants were given either lutein (10 mg), lutein plus antioxidants and a multivitamin-mineral supplement, or a placebo. When the study ended and the results were analyzed, it was found that those persons in groups given lutein alone or lutein plus the other nutrients experienced notable improvements in vision, while no changes whatsoever in vision took place in the placebo group.

In addition to free radicals, there are other compounds generated in the human body that can set the stage for developing MD or contribute to its worsening. Among these is an age-related pigment called lipofuscin that accumulates in the retinal pigment epithelium (RPE) layer and interferes with its function.

Is there any way in which to partially or completely remove lipofuscin? In neurons and heart cells, yes. There are published studies that show that a drug called centrophenoxine will pull this off. But when the drug was tested in terms of its ability to break-up liposucin deposits in other organs, it failed to do so. However, this said, part of centrophenoxine is a compound called dimethylethanolamine (DMAE) which is lipofusinolytic when used on the skin (according to some experts), and thus might in-and-of-itself help bust up lipofuscin in areas the body that appear impervious to the drug. However, some scientists do not feel that DMAE and some of its metabolites can penetrate the blood brain barrier and therefore would not be available to act on the retina.

Readers interested in using DMAE need to discuss this with an eye doctor knowledgeable concerning its possible merits and contraindications.

 In addition to free radicals and lipofuscin, we all produce compounds called   advanced glycation endproducts (AGEs) that can undermine the biological integrity of the retina and macula. And indeed, scientists have found AGEs in the macula of persons with age-related MD. AGEs are formed in the body as a consequence of the processing or metabolism of glucose (sugar) and fats and proteins. When blood sugar is high – as is true in diabetes – AGE production steps up.

What can be done to reduce production of AGEs or undo their damage? 

For diabetes, keeping blood sugar under control is critical. Also, both diabetics and healthy folks should avoid consuming sugars that favor glycation such as fructose and galactose. Supplementation may also help. For example, the supplement L-carnosine appears to inhibit AGE formation, while alpha lipoic acid, and acetyl-L-carnitine are believed to reduce AGE damage to various tissues including the retina and macula.

The drug aminoguanadine appears to inhibit AGE formation and undo some of its damage to tissues throughout the body.

Supplements.  The results of the Age-Related Eye Disease Study (AREDS) showed that 500 milligrams vitamin C, 400 international units (IU) of vitamin E, 15 mg of beta carotene (often as vitamin A - up to 25,000 IU), 80 mg of zinc (as zinc oxide) and 2 mg of copper (cupric oxide) reduced the risk of progressing to moderate or severe vision loss by up to 25 percent in 3,640 individuals in the early stage of the MD. For individuals with moderate to advanced macular degeneration, the AREDS findings suggest that taking high doses of zinc, beta carotene, and vitamins C and E would be effective in reducing the risk of further vision loss. However, note that beta carotene supplementation is not advisable for smokers or those who once smoked (In one study involving beta carotene supplementation the rates of lung cancer shot up in smokers). Also, zinc in doses above 50 mgs. per day can have side effects such as an adverse impact on immune function. 

A body of weak but compelling evidence also suggests that bilberry and OPCs (oligomeric proanthocyanidins), both of which are rich in flavonoids, may prevent or treat macular degeneration.

The flavonoid-rich herb Ginkgo biloba also holds promise for ameliorating MD. In a 6-month, double-blind, placebo-controlled study of 20 people with macular degeneration, use of Ginkgo (160 mg daily) resulted in notable improved visual acuity.  These findings are underscored by results seen in a 24-week, double-blind, comparative study of ninety-nine (99) people with macular degeneration. In this study, a high dose of standardized Gingko extract (240 mg per day) was compared to a lower one (60 mg per day). The participant’s vision improved in both groups, but to a much greater extent in those on the higher dose.

And finally, at least one controlled study found visual benefits in persons with MD who took a combination of acetyl-L-carnitine, fish oil and CoQ10 (Check out CARDIUM).

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