Macular Degeneration

The macula is found at the center of the retina where the incoming rays of light are focused. The macula is very important, being responsible for what we see straight in front of us, the vision needed for detailed activities such as reading and writing, recognizing faces, fine work, and our ability to appreciate color.

Macular Degeneration is a condition whereby the delicate cells of the macula become damaged and stop working. We do not know why this is, although it tends to happen as people get older. Vision loss usually occurs gradually and typically affects both eyes at different rates.

What causes macular degeneration?

The root causes are still unknown. There are two forms of age-related macular degeneration, namely “wet” and “dry”.

  • For many people the visual cells simply cease to function, like the colors fading in an old photograph – this is known as ‘dry’ degeneration. 70% of patients have this “dry” form, which involves thinning of the macular tissues and disturbances in its pigmentation.
  • The other 30% have the “wet” form, which can involve bleeding within and beneath the retina, opaque deposits, and eventually scar tissue. The “wet” form accounts for 90% of all cases of legal blindness amongst macular degeneration patients. The dry form will often begin to convert to wet, with the appearance of abnormal choroidal blood vessels – angiogenesis. The reason why angiogenesis occurs is unknown but it is believed that this additional blood vessel development is somehow caused by deposits being left in the back of the eye. These deposits are similar to age spots on the skin. These new blood vessels are fragile and have a propensity to leak and bleed, eventually forming scar tissue and resulting in irreversible vision loss.
  • Different forms of macular degeneration may occur in younger patients. These non-age-related cases may be linked to heredity, diabetes, nutritional deficits, head injury, infection, or other factors.
  • Inherited macular degeneration, which appears in some families but not in others, is known as macular dystrophy. Since macular degeneration affects most patients later in life, it is difficult to study successive generations in a family. Recent studies of twins indicate that both genetic and non-genetic factors play important roles in age-related macular degeneration. If several members of a family are sufferers then it is very important that other members have their eyes checked regularly.
  • It has been demonstrated that the blue rays of the light spectrum seem to accelerate macular degeneration more than the others. This means that very bright light, such as sunlight or its reflection in the ocean and desert, may worsen macular degeneration. Special sunglasses that block out the blue end of the spectrum may decrease the progress of the disease.
  • Hypertension tends to make some forms of macular degeneration worse, particularly in the “wet” form where the retinal tissues are invaded by new blood vessels. The medications used to treat hypertension have not been shown to have any direct effect on macular degeneration, but they may slow progression of the disease by reducing hypertension.
  • Any type of smoking or exposure to tobacco smoke can accelerate the development of the “wet” type of macular degeneration.

What are the symptoms?

In the early stages your central vision may become blurred or distorted, with things looking an unusual size or shape. This may happen quickly or develop over several months. You may be very sensitive to light or actually see lights that are not there. People with the advanced condition will often notice a blank patch or dark spot in the centre of their sight. This makes activities like reading, writing and recognizing small objects or faces very difficult.

The formation of new blood vessels and exudates (“drusen”) from blood vessels in and under the macula is often the first physical sign that macular degeneration may develop. In addition, the following signs may be indicative of macular problems and anyone experiencing these symptoms should consult an ophthalmologist immediately:

  • The major risk factors: aging, atherosclerosis and hypertension.
  • Straight lines appear distorted and, in some cases, the center of vision appears more distorted than the rest of the scene.
  • A dark, blurry area or “white-out” appears in the center of vision.
  • Color perception changes or diminishes.

The following are NOT known to be linked to macular degeneration: floaters (moving spots caused by debris floating in the vitreous fluid between the lens and the retina); dry eye syndromes; cataracts and cataract surgery.

Early detection is important because a patient destined to develop macular degeneration can sometimes be treated before symptoms appear and this may delay or reduce the severity of the disease. Furthermore, as we develop better treatments for macular degeneration, whether they are medicinal, surgical, or low vision aids, those patients diagnosed with macular degeneration can sooner benefit from them.

Is there a cure?

At this time there is no known cure for macular degeneration. In some cases, macular degeneration may be active and then slow down considerably, or even stop progressing for many years. There are ways to slow macular degeneration, depending on the type and the degree of the condition. Current treatments fall into three main categories:

  • Nutritional Intervention.
  • Surgery. Laser surgery to remove the scar produced by macular degeneration has been successful in about 10% of people with disciform degeneration, mainly the younger patients. If the degeneration is associated with leaking blood vessels in the center of the macula and vision is worse than 20/70 then laser surgery called photocoagulation is recommended. This will not improve vision but generally reduces further vision loss. Unfortunately for most people, the area of degeneration is in the middle of the macula, at its focal point. This means that treatment cannot be given because the scars produced by the laser would make central vision worse rather than better. ‘Dry’ degeneration cannot be treated by laser.

    Retinal transplantation is a new experimental approach to macular degeneration, but will require research to determine its safety and effectiveness.
  • Making the most of remaining vision. Low vision aids (such as brighter reading lights, magnifying glasses and more sophisticated devices) and techniques for maximizing the use of peripheral vision are used to help patients adapt better to their loss of central vision.

What is the usual outcome?

There is some good news: macular degeneration is not painful, and never leads to total blindness. It is the most common cause of poor sight in people over 60 but never leads to complete sight loss because it is only the central vision that is affected. Macular degeneration never affects vision at the outer edges of the eye, so most sufferers will have enough side vision to get around and keep their independence.

The bad news is that if you have macular degeneration in one eye then it will usually develop in the other also. In the early stages, only one eye may be affected, but as the disease progresses, both eyes are usually affected. Even with a loss of central vision, however, color vision and peripheral vision may remain clear.

 


Signs, symptoms & indicators of Macular Degeneration

Symptoms - Head - Eyes/Ocular  

Vision disturbances

In the early stages, central vision may be blurred or distorted, with things looking an unusual size or shape. This may happen quickly or develop over several months.



 

(High) sensitivity to bright light

Those suffering from macular degeneration may be very sensitive to light or actually see lights that are not there.




Conditions that suggest Macular Degeneration

Organ Health  



Risk factors for Macular Degeneration

Environment / Toxicity  

Cigarette Smoke Damage

Any type of smoking or exposure to tobacco smoke can accelerate the development of the “wet” type of macular degeneration. Smokers on average exhibit only half the density of yellow macular pigment (lutein and zeaxanthin) and develop macular degeneration 7 years sooner than non-smokers.



Family History  

Macular degeneration in family

Children and young people can suffer from an inherited form of macular degeneration called macular dystrophy. Sometimes several members of a family will suffer from this, and if this is the case in your family it is very important that you have your eyes checked regularly.




Macular Degeneration suggests the following may be present

Environment / Toxicity  

Cigarette Smoke Damage

Any type of smoking or exposure to tobacco smoke can accelerate the development of the “wet” type of macular degeneration. Smokers on average exhibit only half the density of yellow macular pigment (lutein and zeaxanthin) and develop macular degeneration 7 years sooner than non-smokers.




Recommendations for Macular Degeneration

Amino Acid / Protein  

Glutathione

Researchers have found that age-related macular degeneration correlates with low glutathione levels. When taking into consideration other variables such as smoking, age, cardiovascular disease and multivitamin use, depletion of glutathione by itself was thought to be a major contributing factor behind macular degeneration. [British Journal of Ophthalmology, 1994; 78 [10], pp.791-4)]



Animal-based  

Fish Oil / Krill

One component of fish oil is docosahexaenoic acid (DHA). DHA builds up in the eye near light-sensing nerve cells.

National Eye Institute researcher John Paul SanGiovanni, ScD, and colleagues analyzed dietary data from 4,513 60 to 80 year-old participants in the Age-Related Eye Disease Study. Those who ate fish more than twice a week were half as likely to get macular degeneration as those who ate no fish at all. More than one weekly portion of broiled/baked fish or tuna lowered the risk by a third.

“The risk for [age-related macular degeneration] was significantly decreased for the highest versus the lowest quintiles of total [omega-3 fatty acids] intake,” SanGiovanni and colleagues write in their abstract. [Association for Research in Vision and Ophthalmology 2003, Fort Lauderdale, Fla., May 4-9, 2003]



Botanical  

Bindweed (Convolvulus arvensis)

Bindweed prevents new vessel growth and may help stop the scarring and permanent damage seen with wet macular degeneration. The suggested dose is two 250mg capsules per day.

Convulvulus arvensis is available as Vascustatin, the most potent natural antineovascular/antiangioneogenesis remedy available. This is indicated in wet macular degeneration, especially where neovascularization is already documented.



 

Bilberry (Vaccinium myrtillus)

Bilberry contains compounds which act as antioxidants in the retina, making it a possible preventive measure for macular degeneration [Klin Monatsbl Augenheikld Beih 1981;178: pp.386-9]. It also strengthens capillaries in the retina and reduces hemorrhaging [Minerva Med 1977;68: pp.3565-81]. An oral dose is in the range of 40 to 80mg (24% anthocyanosides) per day.



 

Ginkgo Biloba

Ginkgo Biloba appears to reduce the risk of macular degeneration. [Recent Results in Pharmacology and Clinic, Fuenfgeld FW, ed. Berlin: Springer-Verlag, 1988; pp.231-6]



Diet  

Increased Fruit/Vegetable Consumption

There is evidence that eating fresh fruits and dark green, leafy vegetables (such as spinach and collard greens) may delay or reduce the severity of age-related macular degeneration.



 

Low Fat Diet

Some scientists have suggested an association between macular degeneration and high saturated fat, low carotenoid pigments, and other substances in the diet.



Mineral  

Zinc

Oral use of zinc has produced improvement in vision. Intravenous administration along with selenium have demonstrated benefits in the treatment of macular degeneration. According to researchers at Harvard University, however, zinc has shown mixed results. [Arch Ophthalmol 1988:106, pp.192-8]



Nutrient  

Lutein / Zeaxanthin

Lutein, an antioxidant found in spinach and kale, works extremely well in protecting the retina against sunlight damage [Methods Enzymol 1992:213: pp.360-6]. Supplementation with 6mg of Lutein daily may decrease the occurrence of macular degeneration by more than 50% [JAMA 1994:272: pp.1413-20]. Lutein is one of the primary antioxidants for the macula rather than for the lens of the eye.

Six months of lutein 15mg per day, vitamin E 20mg per day and nicotinamide 18mg per day improved electrophysiologic measures of macular function in a pilot study of 30 patients with early age-related maculopathy as well as in eight healthy people who served as controls. [Ophthalmology 2003;110(1): pp.51-60]

The prevention of macular degeneration requires a lower dose of lutein and zeazanthin than does treating an already exisitng condition.

However, a study of 2,335 adults in Australia over a period of 5 years suggests that an increased intake of lutein, zeazanthin or other antioxidants may not have a protective effect. [Ophthalmology 2002;109(12): pp.2272-8]



 

CoQ10 (Ubiquin-one/ol)

A researcher at the University of Rome in Italy, reported that CoQ10 may improve retinal function in patients with age-related macular degeneration by improving the performance of mitochondria in the retinal pigment epithelium.

Dr. Feher and associates treated 14 patients diagnosed with early age-related macular degeneration using a preparation that included CoQ10, acetyl-L-carnitine, polyunsaturated fatty acids, and vitamin E. A matched control group received vitamin E alone. A number of tests were then performed at 3, 6, 9, 12, and 24 months.

In patients receiving the CoQ10 mixture, all functions were slightly improved after three months and remained level throughout the two-year study period, while degeneration and visual function among participants in the control group continued to slowly decline. [Ophthalmol. 2003 Sept- Oct:217(5):351-7]



 


Vitamins  

Vitamin D

Age-related vision changes result in large part from changes is the outer retina of the eye, which is subject to inflammation and cell loss. Glen Jeffery, from the Institute of Ophthalmology at University College London (United Kingdom), and colleagues fed old mice vitamin D for six weeks, observing that inflammation was reduced, the retinal debris partially removed, and tests showed that the animals’ vision was improved.

The researchers identified two changes taking place in the eyes of the mice that they posit that accounted for this improvement. Firstly, the number of potentially damaging cells, called macrophages, were reduced considerably in the eyes of the mice given vitamin D. Giving mice vitamin D not only led to reduced numbers of macrophages in the eye, but also triggered the remaining macrophages to change to a different configuration. Rather than damaging the eye the researchers think that in their new configuration macrophages actively worked to reduce inflammation and clear up debris.

The second change the researchers saw in the eyes of mice given vitamin D was a reduction in deposits of a toxic molecule called amyloid beta that accumulates with age. Inflammation and the accumulation of amyloid beta are known to contribute, in humans, to an increased risk of age-related macular degeneration (AMD), the largest cause of blindness in people over 50 in the developed world.

The researchers submit that, based on their findings in mice, giving vitamin D supplements to people who are at risk of AMD might be a simple way of helping to prevent the disease. [“Vitamin D rejuvenates aging eyes by reducing inflammation, clearing amyloid beta and improving visual function.” Neurobiology of Aging, 2 January 2012.]



 

Vitamin C (Ascorbic Acid)

Taking anti-oxidants such as vitamins C and E has beneficial protective effects against age-related macular degeneration (AMD). Since oxidative damage of the eye can cause macular degeneration, taking antioxidants may lower the disease’s occurrence. People with high levels of vitamin C, vitamin E, and selenium appear to have a 70% lower risk of developing macular degeneration. [Arch Ophthalmol, December 1995:113(12, 15): pp.18-23, Arch Ophthalmol 1993:111: pp.104-9]

Long-term use of multiple antioxidants plus zinc and copper clearly reduced the risk of developing advanced AMD and the rate of visual acuity loss in a randomized, double-blind, placebo-controlled trial of 3,640 older adults (aged 55-80 years) with preexisting retinal abnormalities, advanced AMD or vision loss due to AMD who were followed for an average of 6.3 years. [AREDS Report No. 8. Arch Ophthalmol 2001;119(10): pp.1417-1436]

Vitamin E use (500IU per day) alone did not produce any benefit in a 4 year study regarding the development or progression of age related macular degeneration. [BMJ 2002;325(7354): pp.11-14]



Key

Weak or unproven link
Strong or generally accepted link
May do some good
Likely to help
Highly recommended

Glossary

Retina

A 10-layered, frail nervous tissue membrane of the eye, parallel with the optic nerve. It receives images of outer objects and carries sight signals through the optic nerve to the brain.

Macular Degeneration

Increasingly poor eyesight often accompanied by light sensitivity, distorted vision and a blank or dark patch in the center of vision.

Scar Tissue

Fibrous tissue replacing normal tissues destroyed by injury or disease.

Age Spots

Also called "liver spots", these are flat, brown areas usually found on the face, hands, back and feet. They vary in size from 1/8 of an inch to several inches (0.3cm to several cm) and are associated with aging, but long-term sun exposure is also a major cause.

Diabetes Mellitus

A disease with increased blood glucose levels due to lack or ineffectiveness of insulin. Diabetes is found in two forms; insulin-dependent diabetes (juvenile-onset) and non-insulin-dependent (adult-onset). Symptoms include increased thirst; increased urination; weight loss in spite of increased appetite; fatigue; nausea; vomiting; frequent infections including bladder, vaginal, and skin; blurred vision; impotence in men; bad breath; cessation of menses; diminished skin fullness. Other symptoms include bleeding gums; ear noise/buzzing; diarrhea; depression; confusion.

Hypertension

High blood pressure. Hypertension increases the risk of heart attack, stroke, and kidney failure because it adds to the workload of the heart, causing it to enlarge and, over time, to weaken; in addition, it may damage the walls of the arteries.

Atherosclerosis

Common form of arteriosclerosis associated with the formation of atheromas which are deposits of yellow plaques containing cholesterol, lipids, and lipophages within the intima and inner media of arteries. This results in a narrowing of the arteries, which reduces the blood and oxygen flow to the heart and brain as well as to other parts of the body and can lead to a heart attack, stroke, or loss of function or gangrene of other tissues.

Cataract

A steadily worsening disease of the eye in which the lens becomes cloudy as a result of the precipitation of proteins. Most cataracts are caused by the functions of the body breaking down. Eye trauma, such as from a puncture wound, may also result in cataracts.

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