Age-Related Macular Degeneration
What is age-related macular degeneration?
Age-related macular degeneration is a disorder that is characterised by the appearance of small yellow spots (drusen) on the retina surface. It mainly affects the central retina. This is the part that is important for reading and seeing fine detail such as recognising faces or reading small letters. The disease can be broadly grouped into early, intermediate and advanced age-related macular degeneration.
Features of early macular degeneration are very common. It is very common for opticians to find small drusen on a routine eye test without the patient noticing any problems with the vision. This does not usually require any treatment. There is no proven benefit in taking vitamin supplements at this stage.
Intermediate macular degeneration is still of the dry type. The drusen appear larger in size and there may be pigmentary changes in the retina. If this is noticed, your ophthalmologist may recommend the importance of vitamin and lutein supplements in order to slow down the progression.
Advanced macular degeneration is characterised by either the retina becoming very thin (atrophy) or the development of abnormal blood vessels below the retina (wet AMD). The vision can then start to reduce more dramatically. Only about 10%- 15% of patients will develop advanced macular degeneration.
Symptoms of age-related macular degeneration:
In the early stages, most people do not have any problems with their vision. As the disease progresses to an intermediate stage, there may be some difficulty with tasks such as reading.
If symptoms of wet age-related macular degeneration develop, your eyes must be examined by an eye doctor urgently. The warning symptoms are:
- Distortion – this results in straight lines looking crooked or letters may crowd into each other when you try to read.
- A rapid reduction in your reading or distance vision (vision can fall within days or weeks).
- A grey patch may develop in the centre of your vision or you may notice an area where letters seem to disappear when you look directly at them.
It is important to monitor your eyes with an Amsler chart if you have intermediate stage macular degeneration. This will help to detect wet macular degeneration at an early stage before permanent damage sets in. Early treatment will help give the best results to protect your vision. You can download your free Amsler chart here.
Managing intermediate (dry) macular degeneration:
The aim of any intervention would be to reduce the risk of the disease progressing to the advanced stage. There are certain measures that are considered to be helpful. These include:
- Avoidance of smoking; this is critical as smoking carries one of the highest risks for progression.
- Make sure your blood pressure is well controlled
- A diet rich in antioxidants; these are commonly found in coloured vegetables and fruits, especially berries such as blueberries and bilberries.
- Vitamin supplements; although there are many different preparations available that claim to offer protection, the most comprehensive study were the AREDS 1 & 2 studies. The supplements that resemble the AREDS 2 formula include Viteyes 2 and Macushield Gold. Avoid high dose vitamin A supplements. This would include many fish oil and cod liver oil supplements. A normal dietary intake of fish is not harmful and may offer some benefits as a source of omega oils.
- Wearing protective sunglasses; although most of the harmful ultraviolet is already filtered by structures in your eyes, there may be some benefit to limiting oxidative stress from high energy light waves. This is likely to be helpful when you are in bright sunlight or by the seaside. More research is needed to clarify this.
What will happen at my consultation?
Your consultation in London will consist of a discussion with your doctor and a thorough eye examination. You will then have an OCT scan and some patients may need a fluorescein angiogram as well. More information about these tests can be found in the patient information section above.
If the tests find evidence of wet age-related macular degeneration, you will be offered urgent treatment that can take place the same day (if your are insured, your insurer will need to approve this first).
It is important to remember that a diagnosis of wet macular degeneration does not mean that you will go blind. Vision can be protected in 90% of patients. Up to 60% of patients can have an increase in their vision. The best results are obtained when treatment is given early.
Treating wet macular degeneration:
This involves giving injections into the eye. The drugs used are designed to stop the abnormal blood vessels leaking and reduce the risk of bleeding and scarring that can cause permanent loss of vision. Injections need to be given as a course of injections. Most patients will need between 5-6 in one year.
Having an injection is not painful. The eyelids are cleaned with Iodine and local anaesthetic eye drops will be used to numb the eye surface. A speculum is used to keep the eye open and the injection is given with a very fine needle (almost as thin as an eyelash). You will feel a sensation of pressure (like a finger pressing on the eye) but this will not usually feel sharp or painful. The whole process takes less than 10 minutes.
What to expect after the injection:
The eye will feel like it has a small piece of grit under the lids. This is where the needle entered the eye. This sensation will usually pass within a day and can be easily managed by using artificial tear drops.
There may be a small blood spot on the eye surface where the needle entered the eye. This is harmless and will disappear after about a week.
Immediately after the injection, your vision may be blurred. This will resolve within a few hours. You may also notice small black spots floating in the bottom of your vision. The commonest reason for this is small air bubbles that are within the drug solution and these will clear within a day.
You can assume all normal tasks after an injection. However, it is important to avoid contaminating the eye surface with unclean water or dirt. We advise patients not to perform tasks such as gardening or swimming for 5 days after the injection.
There is a 1:1000 risk of developing a sight-threatening infection after an injection into the eye. This is very rare but needs to be treated urgently. If you develop either worsening pain, worsening redness of the eye or worsening vision in the first 10 days after an injection, you must contact your doctor immediately.
Important points to remember:
Dry AMD is very common and most people maintain very good vision in the long term.
Developing advanced macular degeneration (wet or atrophic) only occurs in 10-15% of patients with dry macular degeneration.
Monitoring the dry macular degeneration with an Amsler chart is an excellent way of monitoring for any progression, so that treatment can be given before permanent damage occurs.
You can download your free Amsler chart here.
If there is any sudden worsening of vision or the development of distortion, you must seek help immediately.
With prompt treatment of wet macular degeneration, vision can be preserved to an excellent level. Early treatment gives the best chance of protecting your vision.