Age-related macular degeneration
Age-related macular degeneration (AMD) is a degenerative disease of the retina (the light detecting part of the eye) and is the most common cause of severe vision loss in elderly people in the western world.
AMD is a progressive condition in the eye which, if left untreated, may cause you to lose the central vision in your eye(s) because the central part of your retina (the film in the back of your eye) is swollen. This swelling is caused by abnormal blood vessels growing in the retina that are very fragile and therefore leak blood and fluid. It is this fluid accumulation and swelling that is mostly responsible for your vision loss.
There are two types of macular degeneration – Wet and Dry.
The wet form of macular degeneration is the more sinister type and can cause rapid loss of your central vision (reading, TV, recognising faces, driving and colour vision), but fortunately it only rarely causes loss of peripheral vision. Without treatment most patients will lose vision to the level of legal blindness in that eye (unable to see any letters on the vision test chart). Unfortunately many people may go on to have both eyes affected (about 12-14% chance per year or 50-75% chance by 5 years). You will have been given some information separately regarding things you can do (diet, stop smoking, sunglasses, vitamin supplements, monitoring with Amsler grid, magnifiers). You will not harm your eyes by using them or put any extra strain on your good eye.
Fortunately, the treatments for wet macular degeneration (or leaky blood vessels) are improving all the time. Fluorescein angiograms (photographs taken of the back of your eye, after a special yellow dye is injected into your vein) are how we confirm whether you have wet macular degeneration and also show us what subtype of leaky blood vessel you have. Another special photograph called an OCT is essential for monitoring how your treatment is going. Medicare covers most of your fluorescein angiogram cost however there is currently no rebate from Medicare for the OCT.
The subtype will determine the best treatment for your leaky blood vessel. 10 years ago not much could be done at all. Only an occasional leaky blood vessel could be treated with laser coagulation (hot laser) and this is still the best treatment for some types of wet macular degeneration.
Since 2000 photodynamic therapy (PDT) with Verteporforin has been available in Australia. Unfortunately it is not suitable for all types of wet macular degeneration. The fluorescein angiogram will determine whether your leaky blood vessel is suitable for PDT.
You will be given more information about PDT if relevant to you, but as Visudyne is light sensitive you will need to stay indoors and keep covered for 2 days to prevent sunburn. PDT treatment is given every 3 months if needed and patients on average require 3 treatments in the first year and 2 treatments in the second year of treatment.
Lucentis is a different medication (called an anti-VEGF agent) that works particularly well to make the leaky blood vessel less leaky. It is given as an injection into the eye every month for up to 2 years. Studies of Lucentis indicate it is more effective than any other treatment we have for macular degeneration and it works in all subtypes. It seems to hold things stable in 90-95% and may even improve vision in 30-40%.
The best treatment for your macular degeneration may be a combination of the above treatments and in most people will require regular repeated treatments for up to 2 years. You will likely be checked every 6 weeks and have fluorescein angiograms about every 3 months. Fortunately we now have much more we can do for wet macular degeneration so that there is hope is retaining some vision in a condition which without treatment typically leads to severe vision loss