Macular Degeneration

Macular degeneration

The macula is the central part of the retina we use for seeing fine detail such as reading a book or reading road signs. Macular degeneration covers a number of conditions which affect the macula. Macular degeneration normally starts as we get older and, hence it is often referred to as age-related macular degeneration (AMD, or ARMD). It is generally classified as being “dry” or “wet”.

Dry AMD

This is by far the most common type of macular degeneration. It causes gradual deterioration of the macula due to age-related degenerative changes, usually over many years. There is currently no effective treatment for dry AMD, but a lot of research is going on to find new treatments. If you have been diagnosed with dry AMD, but notice a sudden change in your vision, you must seek advice urgently as people with dry AMD can develop wet AMD as well.

Wet AMD

Wet AMD is caused by abnormal blood vessels growing behind the retina. These leak fluid and can cause rapid loss of central vision. The earliest symptom is distortion where straight lines look curved or wavy. If caught early, wet AMD can be treated, hence it is important to seek advice urgently if you notice a sudden onset of distorted vision or central area of blurred vision.

Apart from distortion, AMD can also cause the following symptoms:

  • Vision may become blurred or patchy
  • Dark spots could appear in the centre of your vision
  • Vision can fade in and out
  • You may find bright light glaring and uncomfortable
  • You may find it difficult to adapt to changes in lighting levels
  • Words might disappear when you are reading

Can AMD be prevented?

The causes of AMD are varied and some people are more susceptible to it due to genetic factors. The current advice on known risk factors includes:

Smoking

Although some people who have never smoked can get AMD as well, smoking is recognized as a high risk factor.

Diet

A diet rich in dark green vegetables such as kale and broccoli, and regular consumption of oily fish is believed to have a protective effect against age-related damage to the macula. Other benefical foodstuffs include blueberries and prunes.

Dietary supplements

There are various dietary supplements aimed at offering protection from AMD available from optometrists and health shops. Whilst there is strong evidence that supplements are beneficial to people diagnosed with AMD, there is some debate on their value purely as a protective measure.

Some experts feel having a suitable diet, as explained above, is as effective as taking supplements. Others feel it is difficult for most people to have a regular intake of the beneficial foodstuffs in sufficient quantities and this is made more difficult for people over 50 due to poor absorption of nutrients in the gut. Hence, they feel taking dietary supplements guarantees optimum protection.

There’s an argument for people with close family history of AMD to consider taking supplements as an “insurance policy” with the philosophy “it won’t do you any harm, but, it may do you some good!”.

If you are a smoker and you are considering taking dietary supplements, please contact us for further advice as some supplements are not suitable for smokers.

Blue Light

There is evidence that exposure to UV and short wavelength blue light can cause retinal damage, hence, wearing suitable sun protection is advisable for everyone. There is an increasing interest in possible retinal damage from long term exposure to short wavelength blue light (400-450nm) from modern indoor lighting and mobile devices. It is generally accepted that the levels emitted by devices such as laptops, tablets and mobile phones are too low to cause any concern.

Indoor LED and low voltage lighting is known to emit more blue light compared to older style incandescent or halogen lighting. However, there is insufficient evidence at present to say if this increases the risk of developing AMD or not. A number of spectacle lens manufacturers have developed special coatings to reduce the amount of blue light reaching the eyes. It is too early to know if these products provide effective protection, and a healthy approach might be to treat them as an “insurance policy” in the same way as dietary supplements.

You can get more information on macular degeneration at the following links: