Dry age-related macular degeneration
Dry AMD is the common form of macular degeneration — around 80 to 90 per cent of cases. These are the questions people ask about it in clinic.
What is the macula, and what has gone wrong?
The macula is the small central part of the retina responsible for detailed vision: reading, recognising faces, driving, fine work.
In dry AMD, deposits called drusen build up underneath the retina, and the light-sensing cells above them gradually thin and stop working. It happens slowly, over years.
Will I go blind?
No. This is the fear almost everyone arrives with, and the answer is no.
AMD affects central vision, not peripheral vision. You keep the vision you use to move around a room, and dry AMD does not cause total blindness.
That does not make it trivial — losing central detail affects reading, faces and driving, and that matters enormously. But the fear of complete darkness is one worth setting aside.
How quickly does it progress?
Slowly, in most people. Many have mild changes for many years and never lose meaningful vision.
The number that matters is not how fast the dry AMD itself changes, but the risk of it converting to wet AMD, which behaves completely differently and moves in weeks.
What should I be watching for?
Three things matter more than anything else on this page:
- Straight lines looking bent, wavy or kinked — door frames, window frames, the line where the wall meets the ceiling, the lines on a page
- A new blurred, grey or missing patch in the centre of your vision
- A sudden drop in vision in one eye
If any of those appear, contact the clinic or your optometrist without waiting. Do not wait for your next scheduled appointment, and do not wait to see whether it settles.
Those symptoms suggest conversion to wet AMD, which is very treatable but only if caught early.
What are the everyday signs of dry AMD itself?
These come on gradually, and people often put them down to needing new glasses:
- Needing much more light to read. One of the earliest and most reliable signs.
- Difficulty in dim light, and slower adjustment when going from bright to dark.
- Loss of contrast — difficulty telling apart similar colours, or seeing a step in low light.
- Difficulty recognising faces, particularly at a distance.
- Words blurring or letters dropping out when reading.
None of these is an emergency. They are worth mentioning at your appointment, because they help judge how much the macula is affected.
Why do I have to check each eye separately?
Because your good eye compensates for the other one so completely that a substantial change can go unnoticed for months. This is the part people most often get wrong.
Once a day, with your glasses on, in decent light, cover one eye and look at something with straight lines. A door frame does perfectly well. Then swap. It takes ten seconds.
What is an Amsler grid?
A small chart of squares with a dot in the centre. Put it on the fridge and use it the same way — one eye at a time, glasses on, looking at the central dot.
If lines that were straight yesterday are wavy today, that is exactly the finding we want to know about.
What is geographic atrophy?
The advanced form of dry AMD, where patches of retinal cells have been lost altogether. It causes blank areas in central vision that gradually enlarge.
Treatments aimed at slowing it now exist and are covered on the treatments for dry AMD page.
What causes it, and is it my fault?
Age is the main factor, and you cannot do anything about that. Genetics play a substantial part too.
The one thing that is both major and modifiable is smoking, which is by a distance the biggest controllable risk factor.
Other contributors:
- Family history — a first-degree relative with AMD raises your risk
- Ethnicity — commoner in people of Northern European descent
- Being significantly overweight, which is associated with faster progression
- A diet low in antioxidants and omega-3
- High blood pressure and cardiovascular disease
Nobody develops AMD through carelessness. But if you smoke, stopping is the single most useful thing available to you.
Will my children get it?
Family history does increase risk, so it is worth them knowing and having regular eye tests from middle age onward. It is not a guarantee, and there is no genetic test in routine use for this.
Next steps
Patients — contact the clinic to arrange an appointment.
GPs and optometrists — refer directly to Limerick or Ennis, including by Healthmail.