How to manage dry and wet AMD
Dr. Michael Dollin, MD, FRCSC, Vitreoretinal Surgeon
Duration: 3 minute, 50 seconds
When diagnosing dry AMD, its usually Drusen that we see in the earliest findings. Drusen are dark spots that slowly form on the retina that can grow in size over time. They can cause visual disturbances and even vision loss.
Diagnosis can sometimes be tricky because it tends to develop in one eye and then the other, so if the patient still has one good eye, they may ignore the distortion in the other eye. When a person has a strong family history of who might have significant risk factors, like smokers, or people where they may have a lot of Drusen already formed in their eye, then we might give them a special grid paper called an Amsler grid that they could use on a daily basis to test individually to watch out for those visual changes that can affect vision or can cause vision loss or distortion.
There is also another form of dry macular degeneration that's more advanced. It's called geographic atrophy, where the pigment cells in the back of the eye start to die. This can cause patches on the retina that lose their ability to see. This is an example of one progression in further deterioration that can occur from early dry macular degeneration.
The other progressive development is to the wet kind of macular degeneration, which is when new blood vessels start to grow into the back of the eye behind the retina. Both of these changes from early to more advanced macular degeneration is best diagnosed by an ophthalmologist where they can do testing such as laser photography of the retina to assist in the diagnosis.
Typically, the treatment for early dry macular degeneration depends on how many Drusen you have in the back of the eye. If we diagnose a patient with moderate to severe AMD, we tend to start them on a special multivitamin that has a particular vitamin combination that has been tested and is known to slow the progression towards more advanced forms of macular degeneration, especially the wet kind. These pills are formulated in a dose called AREDS 2. This particular combination can’t prevent age related macular degeneration, but they can help slow the progression of the disease up to 30%, allowing you to keep your vision longer.
If a patient develops more advanced wet macular degeneration, they are typically treated with medicines that are injected into the eye that cause the abnormal blood vessels to dry up and die. These injections are called anti VEGF injections and are administered by a retinal specialist every one to two months. These injections are used to stabilize, and in some cases improve the vision and are the mainstay of the treatment of wet macular degeneration.
For dry macular degeneration, with the advance stage being geographic atrophy, there are emerging treatments that will slow the progression of these areas of pigment cell death and blind spots. These medicines are also injected into the eye and they slow down the inflammatory pathways in the back of the eye that lead to geographic atrophy. They are also administered by injection into the eye typically every one to two months. Injections are typically started on a monthly basis and can then be extended based on the response of the eye to the treatment.
With conditions like dry and wet macular degeneration, the earlier the diagnosis, the less advanced the disease will become and in general, the better the visual outcome. If you think you may be at risk for dry macular degeneration, please don’t hesitate to go to your local eye specialist for proper screening.
If you want testing, you can go to an eye care specialist who will often employ special testing.
Presenter: Dr. Michael Dollin, Ophthalmologist, Ottawa, ON
Local Practitioners: Ophthalmologist
