Wet age-related macular degeneration
Urgent: if straight lines have started to look bent or wavy, or a blurred or blank patch has appeared in the centre of your vision, contact the clinic or your optometrist straight away. Do not wait for your next appointment. Wet AMD responds far better when caught early, and delay costs vision that cannot be recovered.
What is wet AMD?
Abnormal blood vessels grow underneath the retina and leak fluid, and sometimes blood, into the macula. The macula swells, and central vision blurs and distorts.
It is much less common than dry AMD — around one in ten cases — but it is the form responsible for most of the serious vision loss, because it moves quickly.
How fast does it move?
Weeks, not years. That is the crucial difference from dry AMD.
This is why the advice about not waiting matters so much. Someone who reports distortion within days does substantially better than someone who waits for a routine appointment six weeks away.
What does it feel like?
Usually one of three things:
- Straight lines looking bent, wavy or kinked — often noticed on a door frame, a window frame, or the line where the wall meets the ceiling
- A blurred, grey or missing patch appearing in the centre of your vision
- A sudden drop in vision in one eye
There is no pain and no redness. Wet AMD is entirely painless, which is part of why people delay.
I have dry AMD. What are the chances it turns wet?
A minority of people with dry AMD convert, and the risk is higher with intermediate or advanced disease, and higher again if the other eye has already converted.
That is the whole reason for monitoring. It is not that we expect it to happen; it is that if it does, the difference between catching it in days and catching it in months is substantial.
How is it diagnosed?
An OCT scan is the main test. It produces a cross-section of the retina and shows fluid directly, in a few seconds, without dye or needles. It is what confirms wet AMD and what guides every treatment decision afterwards.
OCT angiography can map the abnormal vessels themselves, again without dye.
Fluorescein angiography, where a dye is injected into a vein in the arm and photographs are taken as it passes through the retinal vessels, is used in some cases where the picture is unclear.
Alongside these, your visual acuity is measured and the retina examined directly after dilating drops.
The scanning is available on site, so diagnosis and the decision to treat usually happen in the same visit rather than across several.
Are there treatments other than injections?
Photodynamic therapy and thermal laser were the mainstays before anti-VEGF drugs arrived. They are now used only in selected cases, because injections give substantially better results for the great majority of people.
Is it treatable?
Yes, and this is the genuinely good news.
Wet AMD is treated with anti-VEGF injections, which block the signal driving the abnormal vessels. The leaking stops and the retina dries out.
This has transformed the outlook. Where wet AMD once meant near-certain loss of central vision, most treated patients now keep their vision and a substantial proportion improve.
The full detail — what the injection involves, aftercare, and the warning signs — is on the treatments for wet AMD page.
What if it has already affected one eye?
The other eye needs watching closely, because the risk of it converting is meaningfully higher.
Keep checking each eye separately, every day. This is the group for whom the Amsler grid on the fridge earns its keep.
Will I go blind?
Wet AMD does not cause total blindness. Peripheral vision is not affected, so you keep the vision you use to move around.
Untreated, it can cause severe central vision loss. Treated promptly, most people keep useful central vision.
Next steps
Patients — contact the clinic to arrange an appointment.
GPs and optometrists — refer directly to Limerick or Ennis, including by Healthmail.