Most eye damage happens when you don't even realize it.
Yeah, I did it. I looked. It's not like I haven't looked at the Sun before, and I didn't even properly stare at it, but, like our fearless president, I turned from literally every expert and went my own way. How could I not? Totality! I also didn't have glasses or anything because the eclipse was a total surprise event as all eclipses are.
The thing is, I know eye pain. Like, I don't need an expert to tell me not to look at the Sun because I know just how bad it sucks to do actual damage to your eyes that way. Find my tale of snow blindness below.
An interesting thing about eye damage is that it's often insidious. You don't even realize that it's happened until much later when suddenly you're crying and oozing and neither of those things is helping the scratching, scraping feeling now coating the inside of your eyeballs.
With that in mind, I came up with a short list of other ways to fuck up your eyes without even really thinking about it. Some of these causes are also very avoidable―as avoidable as staring at the Sun, even.
I was climbing Mount Adams in Washington state in 2014 over the Fourth of July. My climbing partner had proper climbing eyewear involving protective side flaps to keep any wayward photons from slipping by, but I'm a real cool dude so I just wore a pair of knockoff wayfarer sunglasses. Many other climbers on the route were wearing full-on snow goggles.
The normal Mount Adams climb consists of basically one giant undulating snowfield extending upward for, like, 4,000 vertical feet. In the snowfield's center stretches something of an ad hoc staircase of steps kicked into the snow by weeks' or months' worth of climbing boots. For a day-and-a-half our surroundings were limited to white snowfields and the sky itself. It was awesome.
When I got home I thought I was just tired. My eyes burned a bit. I knew I was more than just tired when I laid down to sleep and found that closing my eyes made it worse, while at the same time the pain was getting worse on its own. It was a burning, scratching feeling, like granules of sand were being smooshed around the surface of my eyes. They wept and oozed. Looking at a computer was out of the question. The ordeal lasted maybe 48 hours. I learned a lesson.
What I had was snow blindness. It's like a sunburn but on your cornea or conjunctiva rather than your skin (but I had that going too). The proper name is photokeratitis. There isn't much you can do about it once the damage has been done. Painkillers and a dark room, mainly.
Better is just to not get snow blindness in the first place, which is easy. For one thing, understand that sunlight at a high elevation above a snowfield is a different beast than normal sunlight. Up here, sunlight is not only less filtered, but it's reflected back by the snow surface. Even on a cloudy day, the snow's reflectivity can have a seemingly outsized effect. The lesson is to wear proper eyewear. Sunglasses or goggles should block out at least 99 percent of UV rays and they should be full coverage. On the mountain, cool-guy sunglasses are just style.
A whole lot more people are going to get diabetes―particularly type 2 diabetes―than are going to climb a mountain. Recent years have seen its prevalence skyrocket in the United States. Generally, it's a disease in which the body loses its ability to regulate glucose levels in the blood, leaving those afflicted with abnormally high levels of the sugar to linger within their vasculature. With nowhere to go―like, say, a cell where it can be converted into useful energy―the sugar causes damage to blood vessels. It's thought that this has to do with interactions between the excess glucose and proteins and fats also present in the bloodstream, which are converted into destructive byproducts.
When that damage occurs in the eye, diabetic retinopathy results. This is a leading cause of blindness and its early stages have virtually no symptoms. Maybe some blurred vision. By the time its effects become noticeable, it may already be too late to save a patient's vision.
First comes macular edema, in which some fluid starts to leak from within the eye's tiny blood vessels. Vision loss can occur at this stage, but things get really dangerous as new, abnormal blood vessels begin to grow in the back of the eye. These are even more prone to hemorrhage. Once blood begins accumulating in the eye, it can take years for it to drain back out, if it does at all.
There are treatments for diabetic retinopathy, but they're not always successful. Better is just to not get it in the first place, which primarily means ensuring that diabetes remains well-manage, and, obviously, diagnosed in the first place.
Hypertension, otherwise known as high-blood pressure, hits the eyes in three general ways. The first is retinopathy similar to the diabetic variation above. Like overfilling a balloon, too much pressure causes the tiny blood vessels of the eye to bubble and swell, potentially leading to tearing and breaking. The ensuing bleeding can block vision―permanently, in some cases.
When this bleeding occurs behind the retina, central serous choroidopathy occurs. As fluid accumulates, pressure builds, with one possible outcome being retinal detachment. This is somewhat less common than retinopathy in diabetics, but it actually occurs with some regularity in non-diabetics as the result of stress.
Finally, screwy blood flow in the eye can lead to optic neuropathy. Simply, blood no longer makes it to the optic nerve, which can be damaged as a result. And losing nerve cells in the eye naturally leads to vision loss.
Hypertension is very sneaky, notoriously so. One in three adults have it, according to the Centers for Disease Control and Prevention, and it's a leading cause of heart disease and stroke. In many cases, it has basically no symptoms.
With all of that out of the way, it's worth noting that the eyes are incredibly resilient sensory organs. When you figure that eyeballs are really just these exposed sacs of fluid and complex biological machinery sitting in a couple of holes on your face, it's a wonder more people aren't walking around with eyepatches. I've had my eyeball swell up to the point that I couldn't even close the eye. I went to the ER because I thought for sure it was going to burst, but, nah, the docs told me that it's cool, eyes can take it.
Things I've had in my eye: all manner of smoke, salt water, cleaning chemicals, sticks and pine needles, bugs, dog tails, kitchen cabinetry, and on and on. Weigh that resiliency against the amount of information our eyes deliver, and it's kind of miraculous.
The stuff that really gets us in the end are the traumas we may not even at first feel. That includes eclipse eye damage. It's not like a glance at the Sun is going to send a careless eclipse viewer crumpled to the ground. The most likely outcome is basically a snowless version of snowblindness―which includes its delayed symptoms. Not recommended.