Eye problems in aging adults are probably the most common declines in function you see with aging.
These declines in function can lead to vision impairment or significantly altered eyesight – neither of which are desirable in any way, shape, or form. And while you can certainly see some improvements with the introduction of glasses, there is little you can do to reverse these changes once they have occurred.
Gaining an understanding of what changes your eyes experience as you age can give you an indication of what you need to do to prolong age-related declines in vision – keeping you squint-free for as long as possible.
How Do Your Eyes Work?
Your eyes truly are incredible organs. Obviously, you know that they let you see, which is amazing in and of itself, but the way in which they give you sight makes them downright unbelievable.
Light Enters Your Eye
When rays of light come from the outside world, they first enter your eye through the cornea (the clear window at the front of the eye). Behind the cornea sits the iris (the colored part of the eye), with the pupil appearing as the black hole smack-bang in the center of it.
Your cornea acts kind of like a magnifying glass or a funnel, channeling all the light across the iris and into your pupil. Your iris has the ability to enlarge and shrink down to control the amount of light entering the eye (think of a camera shutter opening and closing).
Light is Bent By Your Lense
Once the light has passed through the pupil, it enters your eye’s crystalline lens. The lens of your eye is a clear, flexible structure that shortens and lengthens its width in order to provide focus and clarity to the rays of light entering your eye.
While moving through your lenses, these light rays are bent, so that all of them travel through the fluid in your eye to land on a single, sharp point on the back wall of your eyeball (called your “retina”).
Light Reaches Your Retina
Your retina captures the rays of light and processes them into nerve impulses. These impulses are then transferred across millions upon millions of individual nerve fibers to meet your optic nerve.
From Your Optic Neve to Your Brain
Once the impulses make it to the optic nerve, they are transferred to the “vision center” of your brain, which interprets these impulses and builds an image that you “see” as the world around you.
This whole process happens thousands of times per second, allowing unbroken, real-time vision.
While this process is both amazing and complex, it also provides an explanation as to why your eyes are so susceptible to age-related declines – because there are so many parts that can malfunction and steps that can go wrong!
Why Do Your Eyes Get Worse as You Get Older?
Though technically, any part involved in the complicated process that your eyes use to allow you to see can get messed up as you age, there are a few that tend to get out of whack with great regularity. These tend to be the parts responsible for most of the vision loss you experience as you get older.
Which parts are these? Well, there are four of them! Your:
Let’s check out each of these, and their common malfunctions, in more detail!
Loss of Normal Lens Structure and Function
The lens of the eye is made of mostly water and protein molecules. To work properly, the protein molecules must line up in such a way that the lens is perfectly clear.
As you age, the cells responsible for layering these proteins become less efficient at their job (this is ultimately a normal – and unfortunate – part of the aging process), and you start to see slight alterations in the layering-structure, with some proteins starting to clump together.
In areas where excessive clumping occurs, the lens becomes clouded. This area of clouding is a “cataract”. Cataracts limit the amount of light that can pass through your lens. And less light making it through your lens to your retina, of course, changes the nerve signals that your brain recievies, messing up the picture of the world you “see”.
Changes in Blood Flow to the Eye
This second of the common eye problems in aging adults has, oddly, very little to do with changes in your eyes, themselves.
See, as you get older, you see substantial declines in the cardiovascular system’s ability to move blood throughout the body. While we won’t go into too much detail here, it is worth mentioning that these changes are related to the body’s veins and arteries becoming less functional as you get older, with reduced ability to dilate and allow easy blood flow throughout your body.
While you typically hear about the role of age-related changes in blood flow in the context of cardiovascular diseases (like high blood pressure or atherosclerosis), they can also have serious impacts on the health of your eyes.
You see, the retina within your eye requires a constant supply of blood. This blood brings the retinal cells nutrients and oxygen and removes their waste products. Without these essential nutrient-waste-product-exchange processes, your retinal cells can struggle to function. And poorly functioning retinal cells may not be able to convert light into nerve signals properly, messing with your vision.
Additionally, the tiny blood vessels in the retina are at high risk for developing blood clots if the blood moving through them is going too slowly. This is because these blood vessels hold so little blood and small amounts of blood can clot more easily. (It’s kind of like how small spots of glue become solid faster than large puddles.)
If a blood clot forms in one of these small blood vessels (a condition known as vascular occlusion), blood can no longer flow through your retina properly at all, leading to fluid and waste accumulation, seriously impairing the retina’s ability to properly transform light signals into nerve impulses and altering your vision.
Loss of Normal Eye Fluid Filtering
As I mentioned briefly above, your eye is full of fluid. This fluid helps support the function of the eye. It lets light move on a straight trajectory through the eye and eases the transfer of nutrients between cells. In a very similar fashion to blood circulation, as you age the circulation of this fluid in your eye declines. This can lead to the build-up of excess fluid and harmful metabolites in your eye.
This fluid build-up, a condition known as glaucoma, puts lots of pressure on the inside of your eye. The excess pressure is believed to damage and, eventually, kill off small nerve cells that feed into your optic nerve. Without enough signals from small nerves in your retina, your optic nerve also starts dying.
Loss of retinal and optic nerve signals to your brain seriously disrupts your vision. In fact, it can even lead to complete blindness.
Decreased Health of Your Retinal Cells
We know that the light entering the eye is ultimately the key to vision. But, long-term, your eyes’ exposure to light can actually contribute to vision impairment in aging.
See, while your eyes want to let in visible light, they can’t do so without letting in UV light, too. UV rays come packaged with the sunlight you use to see and they are harmful mutagens. Studies suggest that UV rays can directly cause oxidative damage to key structures within your eye, specifically, the cone- and rod-cells of the retina.
This oxidative damage may cause a decline in the retina’s ability to absorb and transfer light, leading to vision impairment. While this is a phenomenon that requires further research, early evidence suggests that oxidative stress caused by these harmful mutagens may be a key driver of age-related declines in vision.
Read More About Oxidative Damage and Aging HERE
Signs of Eye Problems in Aging Adults
Now you know the common conditions that lead to loss of vision as you age! Luckily, if you catch them early, your ophthalmologist can recommend treatments that can keep your eyesight from getting worse.
Are there any red flags to watch out for that could help tip you off that it’s time to see the eye doctor? Absolutely.
If you notice new or worsening:
- Floaters (small dots or threads) appearing within your field of vision
- Narrowing of your field of view
- Loss of the middle aspect of your vision
- Clouding or blurring of eyesight (which may be accompanied by an inability to focus clearly)
- Blind spots in your field of vision
you should call up your eye doc asap! These may be early signs that your eyesight is in danger!
Take Home Message
Your eyes are some of the most impressive and complex organs in your entire body. Unfortunately, this complexity makes your eyes vulnerable to damage as you age, which can easily result in loss of vision.
Scientists think vision loss results from normal aging processes within the eye, such as altered blood and fluid flow through the eye and damaged eye cells from life-long UV exposure.