Strabismus! What next?

When a person has a chronic condition there is a tendency to think that every little change in one's health is due to that condition. At least that's my excuse for running to the eye doctor today because of problems I've been having seeing double. Let me back up and start again.

A couple of months ago I noticed that when my eyes were really tired, such as when I'd been working at the computer for several hours, my eyesight would drift such that my right and left eyes were seeing things in different places. It was sort of like what you see when you cross your eyes. Except that all I had to do to see double was relax. Bringing the two images back in line was what took effort.

Because it didn't happen all the time and because I could "correct" it with effort, I didn't do anything about it. Then a couple of days ago it seemed to take more effort than normal to bring the images in line. I thought I had read something about people with Parkinson's seeing double so I emailed my neurologist about it. He said nope and recommended that I see an ophthalmologist. I did and he said that instead of Parkinson's it was that chronic condition all of us eventually catch - Old Age. The muscles that normally keep the eyes pointed in the same direction (or at least in the direction the brain interprets as the same) get weaker with age. Mine are usually fine but after too much strain, they can't do it without extra effort.

He then explained that there is an element of the eyeglass prescription that is rarely used but useful in conditions like mine. It is the Prism/Base portion of the prescription, the last two columns in the prescription pictured above (which ISN'T mine, by the way). Eyeglass lenses can be ground so that the eye can be "pointing" out, in, up, down or any combination and yet the person will think the eye is in sync. My doctor actually wrote up two prescriptions for me - one with and one without the prism/base prescription. As you might imagine, fixing tired eyes so they work better makes non-tired eyes have to work a little harder. I have to decide how much I want the one or the other.

By the way, there's a really good explanation of eyeglass prescriptions at OpticsPlanet.com should you want to know even more about eyeglass prescriptions.