Tuesday, May 12, 2009

The eyes have it - a tale of 3 vision problems

I'm recovering from a head cold today, so rather than try to do heavy programming work, I decided to write up a personal story that I've been thinking about lately, for a variety of reasons. 

As anyone who knows me personally can probably attest, I wear glasses and have pretty bad eyesight.  Not many of my friends, and probably not even all of my family, know that I have three distinct vision problems, only one of which is actually addressed by my glasses. I'm going to tell y'all about all three, more or less in the order that I found out about them, and the ways in which they've been treated.

Disclaimer: I'm not an eye doctor, nor an expert in human vision. This is all about what my experience has been. It's entirely likely that I'll make at least one glaring error in my use of some technical term. Feel free to correct me.

Chapter 1: Nearsightedness and Astigmatism
Okay, that probably looks like two different problems, but they're both refractive issues, and they're caused by misshapen eyeballs, and so are corrected easily with eyeglasses. If I remember correctly, I got my first pair of glasses in the 5th grade, when I was 10 years old or so. 

I was pretty astounded at the difference when I put them on - for the first time, I could see the leaves on trees as individual objects. I asked my eye doctor how bad my vision was compared to the 20/20 that's considered "normal" and got the unsatisfying response that the 20/x scale wasn't really a useful measure for people with strong nearsightedness. Since I can barely find the eyechart on the wall at 20 feet without my glasses, I can now understand where he was coming from.

There was some consternation amongst the various parties involved about how it is that I could have gone without glasses as long as I had without anybody noticing that I was blind as a bat. For whatever reason, there wasn't any mandatory screening for vision problems in my elementary school. I got screened for a number of other potential issues, amusingly including colorblindness, but nobody ever stuck an eye chart up on the wall and had me read it.

The biggest issue was probably a simple (dare I say child-like?) assumption on my part that everybody else saw things more or less the same way that I did. So, since I couldn't see the blackboard if I was sitting in the back row, I assumed that nobody else could, either. And if it was critical to the learning process for us to be able to read what the teacher was writing, the school would have arranged the classroom such that it was possible, right?

It probably didn't help that I was also a bit of a daydreamer and a slacker. I think that when I said I didn't know that we had homework due, my teachers and my Mom assumed that I just wasn't paying attention, when in reality, I might have simply not seen the homework assignment written on the board.

As I get older, and more and more of my friends have children, it's occurring to me that there might actually be something useful for other people to learn from my experiences. I think the lesson here is actually a pretty simple one. Parents, talk to your kids about what their sensory experiences are. If someone had at any point between age 2 and age 10 simply asked me whether or not I could see some distant object, or count the number of birds on a telephone wire, or even tacked up an eye chart on the wall and tested me, I might have gotten into glasses sooner.

Alright, so I got glasses at age 10, which helped a lot with being able to see what was written on the blackboard, probably made it a lot safer for me to ride my bicycle around, and generally greatly improved my quality of life. Problem solved, right? Not so much. It turns out that I had another problem, which went unnoticed for several more years, despite going to the eye doctor regularly.

Chapter 2: Strabismus, or the "turned" eye
My right eye has a tendency to turn outwards and upwards, away from whatever it is that I'm looking at. When I was younger, this happened involuntarily, and fairly frequently. These days, I can do it "at will" which is a pretty great way to weird people out if they haven't seen it before. It still tends to happen spontaneously when I'm tired, or when I'm drunk.

Since my left eye is (evidently) my dominant eye, the turning out of my right eye didn't cause me much difficulty, except in one critical visual skill - depth perception. As best as I can remember, I was hit in the face by a baseball or softball while trying to catch it at least a dozen times during my youth. I was also considered pretty "clumsy" in general by most of my friends. 

An interesting aside is that your brain actually uses a lot of other cues besides the convergence of your eyes to judge depth, so it's not exactly true that I didn't have any depth perception. It is true that I had really bad depth perception up close, which is where convergence counts the most - hence my spectacularly-bad performance in the whole "get the glove up in front of the ball before it hits you" task.

This particular quirk in my vision went for quite a while before being discovered. In fact, I think it wasn't noticed until I was examined by a new eye doctor for the first time. The doctor who examined me actually had an intern working with him at the time. When he discovered the eye turn, he called the intern in so he could see how it worked.

Having established that I had this eye problem, the question then became what to do about it. The treatment for this problem varies depending on the ultimate cause, but can include everything from eye exercises, to wearing an eye patch, to surgery. At the time, it was widely believed that any treatment for this condition was essentially useless after about age 10 or so. 

The only recommendation from the eye doctor was that they could put a "prism" correction in my eyeglass lenses, which would help reduce any eyestrain I felt from the misaligned eye. As it turned out, the prism correction didn't do very much, either positive or negative, for me, though it did help my eye appear to other people to be pointing in the right direction.

In the years since, I've met several people who've had the Strabismus surgery, mostly as young children, and overall the success rate doesn't seem to be particularly high. I opted not to have the surgery, and it's worked out pretty well for me. I'd say that if you (or your child) have Strabismus, and someone suggests surgery, you'd do well to get a second opinion, and/or try some of the other treatments, before going forward with the surgery.

Chapter 3: Amblyopia, or "lazy" eye
 It turns out that if you have Strabismus from an early age, and/or if your eyes have significant differences in their refractive power (which mine do), then you've got an excellent chance of developing Amblyopia, which is where your brain adapts to ignore the input from the defective eye.

I had always known that the vision in my right eye was considerably worse than in my left eye, even when I wore my glasses. I had assumed (there's that word again) that the difference had something to do with the difference in astigmatism and nearsightedness between the two eyes. While that was probably part of the cause, it wasn't the whole story.

It turns out that my brain had mostly adapted to not use my right eye, though I still had some amount of vision from it. My right eye provided some peripheral vision on that side, and was essentially ignored for everything else. 

An interesting consequence of this that I discovered sometime in my twenties, was that I actually couldn't read if I covered up my left eye. This was a very strange experience. I could see through my right eye fairly well, and there was an image with shapes on it that I knew I ought to be able to recognize, but I wasn't able to make sense of them, at all.

Chapter 4: What I did about it
It bugged me that my eye was pointing out into space like that, and it really freaked me out that I had one eye that really didn't work at all, so I decided to try to "fix" it. You'll recall that the eye doctor told me that there really wasn't much to be done about this since I was "too old". I figured that if it wasn't going to work, it wasn't likely to hurt to try some things.

And I also figured that you hear about people who suffer traumatic brain injuries of one sort or another, and need to spend years in therapy, while their brain works around the damage. By comparison, working around a mental block on my right eye should be easy, right?

I started working on getting my right eye to point in the right direction. Since I did this on my own, I wasn't following anybody else's accepted eye training program, I just did the things that made sense to me. 

I strengthened my eye muscles and stretched them by repeatedly moving my eyes back and forth to the very limits of their motion. Sometimes I'd go left to right, sometimes top to bottom, sometimes in circles one way or another. I did this for a few minutes at a time, working up to about 1/2 an hour or so. 

I did these self-invented exercises nearly every night for probably a year or so, before I started noticing an improvement. When I first started, it was relatively easy for me to over-strain my right eye by trying to force it to the limit of its motion. Let me tell you, a cramp in your eye muscles is no fun at all. I still have a couple of positions that my right eye really doesn't like to go into, but the range of motion is much improved.

Concurrent with the work on the eye muscles, I tried closing my left eye when I was performing various everyday tasks - watching TV, shopping, driving (not in heavy traffic!), or just walking around. Doing that was always very tiring, and a bit stressful. I tended to get headaches if I tried to do it for very long.

Sometime after I moved to California, I had a breakthrough - occasionally, I'd briefly get my eyes to align properly as I was going about my everyday business, and the whole world would suddenly snap into 3-D perspective. It was really disorienting the first couple of times it happened, but I soon enough got used to it. 

It's a little like those "magic eye" random-dot stereograms. At first, it takes a while to get the knack of getting your eyes to cross by the right amount. Then suddenly, you get it right, and the image jumps out at you. After that, it gets easier to do. Over the course of several more years, I gradually trained myself to keep my eyes pointed in the same place, such that it's now second-nature.

I did go through an irritating period where the convergence of my vision wasn't 100% correct, but I was starting to pick out more detail with my right eye. That caused some double vision and headaches, from time to time. These days, I only have double vision sometimes at night.

Chapter 5: Closing Thoughts
Well, this is already ridiculously long, so I guess I'll save some of the amusing anecdotes I was originally going to include in here for a follow-up post. Mostly I wanted to get the story down so the folks that have heard me wise-cracking about "now" being able to see in 3-D know what I've been talking about. 

I also hope that if someone with relatively mild Strabismus and/or  Amblyopia comes across this article, they'll be somewhat encouraged by my success in overcoming them, even after having a late start. Everybody's case is going to be different, but personally, I'm glad that I made the effort.