Myopic Macular Degeneration can disrupt the central vision of young people making it difficult for them to focus on reading and other activities but there are new treatment options and research which are giving them new hope!
I received this topic by request from a lovely, young woman who has this condition. Although I never examined her myself I feel the need to help others understand the conditions they themselves face and also feel the responsibility to educate others out there on this very important subject. Myopic Macular Degeneration is not to be confused with its similar sounding eye illness, Age-related Macular Degeneration. By contrast, Myopic Macular Degeneration usually happens to young people who have a high amount of nearsight and face complications from elongation of the eye and the stretching of its structures within.
As I was writing this article, I found it to be a tougher topic to present than I thought it would be. There is still much to be learned about the exact reasons and ways this condition progresses. Various treatment options and preventative measures have been tried in an effort to halt this condition but there has not been a true, definitive answer on how to stop it. The good news is, it is starting to draw more and more attention especially with the most recent discoveries of the anti-VEGF drugs being more effective than older treatments such as photodynamic therapy or PDT. (source 4) The exciting thing about anti-VEGF drugs is that they target and block ‘vascular endothelial growth factor’ which they believe is a signal that triggers the growth of new blood vessels. New blood vessel growth below the retina (choroidal neovascularization) is one of the potential dangers in Myopic Macular Degeneration. These anti-VEGF drugs are administered by intravitreal injections at intervals determined by a patient’s doctor in hopes to prevent a recurrence of choroidal neovascularization in the direct center of the retina, the macula. They are giving new hope to patients and doctors alike.
In order to really understand myopic macular degeneration, let’s first talk about just plain myopia or nearsightedness. We’ll then move on to Degenerative Myopia and then to Myopic Macular Degeneration.
Physiological (common) Myopia:
In the simplest of terms, Myopia or Nearsightedness can occur in the eye either because ‘the eye is too long or too strong.’ This means that the eye has an axial length greater than average or the combined ocular power of the cornea and lens is higher than what it should be or both. If the eye is too long or too strong, the image of what you are seeing will focus ‘too soon,’ in front of the retina. These leads to a fuzzy image being captured by the retina and thus results in blurry vision. Usually this disparity of optics can be easily corrected for with contact lenses or glasses which focuses the eye’s image right back to where it should be collected in order to yield good, crisp clear vision. Myopia is usually considered to be just a variation of normal eyes if the prescription is around -6.00 or less and it is said to be “the most common eye disorder worldwide.” (source 1)
If your prescription for glasses is much higher than a -6.00, and has gotten progressively worse as you grew older and into your middle age years, there may be a genetic component to your myopia causing the eye to become very long (in its axial length). Degenerative Myopia can be very dangerous to the health of the eye because it can lead to vision loss by either myopic macular degeneration or by a retinal detachment. Also, “more severe myopia and longer axial lengths have been linked to specific pathologies such as cataract, glaucoma, or lattice degeneration.” (source 2) Patient education and proper understanding of these complications are important steps in trying to help patients who suffer from Degenerative Myopia to avoid potential vision loss.
The elongation of the eye is what happens first in Degenerative Myopia. When the eye is much longer than it is wide, there is stretching of the tissues inside the eye and stretching of the retina. Sometimes stretching the retina is like stretching a t-shirt. If it is stretched too far and for too long, it can start to thin and little tiny holes and tears can develop in the retina. When this happens, your doctor will see signs in your eye such as posterior staphyloma, breaks in Bruch’s membrane and lacquer cracks which are complications of scleral thinning and eye elongation. These set the stage for choroidal neovascularization to occur which is new blood vessel growth just beneath the retina. (source 1) When new blood vessels grow, their walls are immature and they leak blood. This is what causes the damage in Myopic Macular Degeneration. Similar to the mechanism behind the damage in Age-Related Macular Degeneration, Myopic Macular Degeneration occurs when this leaked blood causes tissue damage to the overlying retina. Even if the blood is stopped from leaking further, if it was there long enough, it could have changed the architecture of the retina in such a way that disrupts its proper functioning in that area and can result in central vision loss.
Progression and severity of myopic macular degeneration varies widely among individuals. Some have choroidal neovascularization (CNV) and other complications, others never do. In those who have CNV, recurence is another thing that is not uniform, neither is the frequency of recurrence. Therefore, follow-up and treatments are very different among patients and are determined by the doctor.
So is there anything that can be done to prevent Myopic Macular Degeneration? Well, there are certainly precautions that can be taken in order to take a proactive, preventative approach if you have nearsightedness, high nearsightedness, or degenerative myopia.
- Yearly eye exams with dilation of the pupils to check the integrity of the retina
- Adhere to follow-up schedules recommended by your doctor and take all of their recommendations and advice seriously.
- Some experts say to avoid highly physical activities or sports which could result in a sharp blow or shaking of the head.
- Proper Nutrition, make sure you are giving the cells of the macula and retina the building blocks they need to be as healthy and strong as possible.
- At home monitoring of your central vision with an Amsler Grid as directed by your doctor
- Protecting your eyes (cells of the macula and retina) from the UVA/UVB oxidative damage that can occur in repeated exposure to the sun. Wear proper sun protection/sunglasses.
- Know your warning signs of a retinal detachment, if you see FLASHES of light in your vision or FLOATERS that look like curtains, cobwebs, spots that do not go away and increase in number, go to the eye doctor or ER immediately.
Remember, myopic macular degeneration can happen to young people, it is not an illness that occurs with age. To ensure you have good vision your whole life through, take a proactive approach, find an ophthalmologist or retinal specialist you trust and follow their recommendations to a T. Since much of the treatment is customized to the individual, it is essential you adhere to your recommended follow-up appointments and to their treatment recommendations. It’s ok to ask them questions to understand how your eyes are doing and also to stay current with the latest treatment options available. Degenerative Myopia is re-surging as a hot topic in research and in regards to preventative care for Myopic Macular Degeneration, the future looks bright!
Dear Ms. G;
Thank you for requesting this topic, I hope I have helped you understand it a little bit better. It is a hard topic to cover since so much still remains unknown but I think it is important to review what we know now about it and educate others who may be searching for similar answers or information. If you have any questions at all, I would be more than happy to answer them. You can contact me directly or comment. You are not alone.
Cheryl G. Murphy, OD
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