Macular Degeneration

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MACULAR degeneration (ARMD) is a disorder that is related to growing old, where  central vision is slowly destroyed. It affects the macula of the eye.  

In some patients, ARMD progresses so slowly that you don’t notice it at all until it’s really advanced. In other patients, it progresses rapidly and may lead to a loss of vision in both eyes. ARMD is quite common people who are 60 years of age and older.  

The macula is in the centre of the retina, which is the “screen” that pictures and visuals are portrayed upon at the back of the eye. The retina contains plenty of cones and rods, which are the light-sensitive cells that convert an image into electrical impulses, which are then sent by the optic nerve to the brain.  

The macula contains a profusion of these light-sensitive cells, and is the most sensitive area for detecting central vision, which is needed for seeing objects clearly and for tasks such as reading and driving.  

ARMD has two forms – wet and dry. The dry form is much more common, with more than 85% of patients having it.   

Wet (advanced) ARMD is when abnormal blood vessels behind the retina start to grow under the macula. These new blood vessels are very fine and they often give rise to bleeding and the leakage of fluid, therefore allowing fluid to accumulate behind the eye.  

As a result, the macula begins to build up like a little hill and gets damaged very quickly. Central vision will therefore be rapidly affected. An early symptom of wet ARMD is when straight lines appear wavy.   

The other version is dry ARMD. This is a less severe version than the wet one because the macula cells slowly break down, gradually giving rise to blurred central vision. You might begin to see a blurred spot in the centre of your vision. Over time, as the macula continues to break down, central vision is gradually lost in the affected eye.  

This condition only affects the macula, and therefore it is the CENTRAL vision, what you see in the middle of your eye, that will be affected. And if one eye is affected, it might not be the case with the other eye. 

A common early sign of dry ARMD is the appearance of yellow spots under the retina during a routine eye check-up. This is called drusen. It can only be found when the ophthalmologist dilates your eye and gives you a comprehensive check-up. Drusen itself does not cause blurring of vision. An increase in the size or number of drusen raises your risk of developing either advanced dry or wet ARMD.  

The most common symptom of dry ARMD is slightly blurred vision. It may start off when you find yourself having difficulty recognising faces, needing more light for reading and fine tasks, like needlework. Then you may start seeing a blurred spot in the centre of your vision.   

Dry ARMD usually affects both eyes, though either eye can also be affected.   

Finally, in advanced dry ARMD, the blurred spot may get bigger and darker, taking more of your central vision. Now you can only read or recognise faces only when they are very close to you.   

Be careful. When dry ARMD affects one eye only, you may not notice any changes in your overall vision. So if any blurriness occurs at all in your vision, you should see an ophthalmologist and not attribute it to mere aging.   

All people who have the wet form had the dry form first. The wet form is considered advanced.   

Age is actually the greatest risk factor, especially if you are older than 60. Other risk factors include smoking, obesity (Yes, if you are fat, there is a link!), and if you have immediate family members who are having the disorder. Immediate family members mean your mother and your father, or your brother and your sister.Women appear to be at greater risk than men.  

Wet ARMD can be treated with laser surgery, photodynamic therapy, and injections into the eye. All these serve to destroy those fragile, leaky blood vessels. However, none of them is a cure. The loss of vision may progress despite treatment.  

It has been found that dry ARMD can be slowed down by taking a specific high-dose formulation of antioxidants and zinc.  

(Written by Dr Y.L.M)