May 10, 2024 – When we're young, we take our macula without any consideration. At the middle of our retina – the deepest layer of the attention, which is filled with photoreceptors and adds color to our world – the macula is sort of a high-resolution camera. When light hits our eyes, the retina's macula bathes our world in a sea of color with astonishingly high visual sharpness.
But as we age, our vision deteriorates. What was once clear becomes foggy, like condensation on a window pane. After some time, a jet-black spot or cloudy circle begins to affect your central vision.
This blind spot will grow larger over time if left untreated, leaving a “macular hole” in the middle of your retina.
This unlucky series of events marks the advanced stage of age-related macular degenerationa dangerous retinal disease that affects about 20 million people within the United States and nearly 200 million people worldwide.
And it's not improving. It's estimated that by 2040, nearly 300 million people worldwide might be affected by the disease. Our options for treating or stopping it are very limited. Read on to learn more.
First, what causes age-related macular degeneration?
“The causes of AMD are varied, and whether you suffer from it depends mainly on age and genetic factors,” says Marco Alejandro Gonzalez, MD, an ophthalmologist and vitreous specialist in Delray Beach, FL.
Because of various genetic makeup, in some people the photoreceptor cells within the macula “basically start to shut down,” he said.
More than 30 genes are involved in the event of AMD, and if a detailed relative (parent, sibling, child) of yours has the disease, you're thrice more more likely to develop it.
Gonzalez explained that the expected increase to 300 million cases by 2040 is especially because of improved diagnostic capabilities, in addition to the undeniable fact that the world is getting older and living longer. (Usually an optician can Recognizing signs of AMD during a routine eye examination.)
Eye experts are still battling probably the most damaging symptom of AMD—the reason behind the cloudy, milky, and even charcoal-colored circles in your central vision: geographic atrophy.
Geographic atrophy can occur in two types of age-related AMD: “dry” AMD and “wet” AMD.
Almost every case of AMD begins as the dry typewhich affects 80 to 90% of AMD patients.
Retinal disease expert Tiarnán Keenan, MD, PhD, painted a vivid picture of geographic atrophy in patients with dry AMD.
“Over time, the circular GA spots spread like wildfire, taking more and more vision with them, often to the point of legal blindness,” he said.
Keenan, a researcher within the Division of Epidemiology and Clinical Applications on the National Eye Institute, recently led a study This study tested the effectiveness of the antibiotic minocycline in slowing the spread of geographic atrophy in dry AMD. The study hypothesized that the body's immune system may play a task in the event of the disease.
When your body's immune system is overactive, microglia cells (immune cells of the central nervous system) can enter the subretinal space and potentially eat away on the macula and its delicate photoreceptors.
Although minocycline has been shown to scale back inflammation and microglial activity in the attention in diabetic retinopathy, it didn't slow the spread of geographic atrophy or vision loss in patients with dry AMD during Keenan's study.
When asked whether microglia activity may need little or no to do with the spread of atrophy, Keenan said that is something to think about: “Perhaps the microglia are just there clearing away the debris… so inhibiting them would probably not slow the progression of the disease.”
In future drug trials, “minocycline or another approach to targeting microglia may be helpful, but this would need to be combined with another therapy and would be ineffective on its own,” he said.
Two sides of the identical disease
In dry AMD, Gonzalez compares macular degeneration to the lack of pixels on a screen. “Some of those pixels burn out… and that's how you typically lose your vision in the dry form.”
Wet AMD is a progressive type of the disease. It causes sudden vision loss because of abnormal blood vessel growth.
“If you don't treat wet AMD quickly, it's game over,” Gonzalez warned. “With wet macular degeneration, vision is lost faster because these blood vessels are wreaking havoc.” These latest blood vessels bleed, causing fluid to accumulate within the macula, which ultimately results in scarring.
Gonzalez make clear why wet AMD occurs. “The wet form is, for some reason, the body's last attempt to 'help' a dying macula. … When these blood vessels start to grow under the retina, they quickly destroy the architecture of the macula.”
Hemostasis in wet AMD
Although wet AMD is less common, it's more treatable than dry AMD. Signs and symptoms could be alleviated with various therapies injected into the attention.
Put simply, Gonzalez said, these therapies for treating wet AMD “all basically do the same thing. They cause a temporary regression of these new blood vessels before they damage the macula.”
The injected medication unblocks these blood vessels and restores the structure of the macula. In this manner, vision could be partially restored, but it surely is simply a short lived improvement and the injections have to be given as much as once a month.
“The degeneration of the cells is still the main problem. You can't prevent that. But the degeneration itself is much slower than the actual vision loss that comes with these blood vessels.”
The battle to develop latest treatments
According to Keenan, “No one has yet been able to prevent geographic atrophy in either form of AMD.” “So that's the main work in this area with studies.”
In December 2023, the FDA approved two latest drugs: Syfovre and Izervay, each of that are only slow geographic atrophy. Degeneration still occurs.
Keenan explained that these two latest drugs are “complement inhibitors…that are given by injection into the eye about once a month.”
“Complement” refers back to the body’s own Complement pathway, a trigger that prompts a protein cascade to reinforce the immune response.
Clinical studies have shown that Syfovre reduces the speed of geographic atrophy by as much as 22% over 2 yearsand Izervay as much as 14% over 1 yr.
Although these drugs represent a latest weapon within the fight against this annoying disease, they are usually not without complications.
“With any injection into the eye there is always a risk of infection because something from outside gets into the eye. That is the biggest risk,” explains Gonzalez.
Infection is rare but could be devastating as you could lose your eye completely. There can be the potential for a harmful response to the injection.
“You have to choose your patients carefully,” Gonzalez said. “Not everyone is a good candidate for these new injections … and the patient will never see any better. … It's harder to sell them than the injections for wet AMD.”
A joint protective measure
Keenan and Gonzalez are each quite confident that the danger of AMD could be reduced through vitamin therapy.
Providing background on the invention of the preventive effects of vitamins, Gonzalez said, “In the early and late 1990s, there were a series of studies that were called age-related eye disease studies.” These are actually referred to as AREDS 1 and AREDS 2.
Researchers have proven that a certain vitamin cocktail slows down degeneration. The simplest is a mixture of antioxidants: vitamins C and E, in addition to lutein and zeaxanthin, all of that are included within the AREDS 2 formula.
People who took these vitamins were less more likely to lose their vision over the subsequent two to 5 years.”[The combo] appear to be complementary and complementary … with a combined treatment effect of 55 to 60%, an excellent safety record and very low cost,” Keenan said.
Gonzalez recommends the AREDS 2 vitamin formula to each of his patients. “It is very easy to take and the side effects are minimal.”
Unfortunately, if your genes make you more susceptible to the disease, changing your diet or taking vitamins may not be effective.
Terrible? Possibly. But not all is lost in this fight.
AMD alertness and what to do next if you are diagnosed
Gonzalez makes it a point to educate his patients before the time for AMD treatment is up. Recognition is key. “The most typical reason a lot of these people come to me 'too late' is that they don't realize there's an issue.”
He explained a typical scenario: “Let's say you've gotten macular degeneration in each eyes at different stages. One of your eyes develops wet macular degeneration… so the higher eye takes over and you could not notice the issue.”
Even if a patient has been diagnosed with AMD, they typically only see a specialist twice a year. Gonzalez often advises his patients to cover one eye to make sure vision is intact in both eyes. “You'll have the opportunity to see subtle differences” in each eye, he said.
This variety of self-care and vigilance could make the difference between having the ability to successfully live with and manage the disease for the remainder of your life or not attempting to get help until it's just too late.
With wet AMD, as mentioned, a series of injections is largely what everyone does. Without prompt, invasive treatment, the purpose of no return is quickly approaching.