My vision therapist set up something really cool for me. She has another adult strabismic in therapy and she set up a time for us to meet and do a 2 hour block of vision therapy together. This other patient, let's call her... Tara, has had 8 surgeries, has been both an esotrope and an exotrope (currently eso), is a pretty severe amblyope in one eye, and has double vision 100 percent of the time. My vision therapist thought it would be good if we got together, because she said we both "speak the same language" and might be able to help each other.
Finally, this Friday, we got a chance to meet and play around with some red/green stuff! It was great. It turns out that Tara's double vision allows her to "cheat" on most red/green exercises, and so far it has been very difficult for her to get any fusion or overlapping of the two doubled images that she sees. The images just don't want to overlap and make a combined picture, and she doesn't know how to move her eyes to move the doubled images over top of each other.
I started to get so interested in what was going on with Tara's double vision that I spent almost the whole time asking her questions and trying different things with her. One of the toys at the VT office was this ancient looking device that looks like two flashlights connected to box, with one flashlight projecting a red circle and one flashlight projecting a green dot.
From what I've read and heard, I seem to remember that vertical misalignment is harder to treat than an exo or eso deviations. If one eye is wandering out horizontally, then it is possible to learn how to pull it in. But if one eye is wandering up, it can be difficult to learn how to pull it down. Or so I've heard. I've also heard that if the vertical deviation isn't too extreme, the brain can compensate and fuse the images, but if it's too far, then it can be really hard.
I thought that maybe if she used a vertical prism, she would have more luck with fusion. I'm not sure if it's frowned upon to use prisms to help with vertical deviations, or if you're just supposed to "deal with it" until you suddenly have the eye strength to do it yourself, but I wanted to try it. So I ran and grabbed the box of loose prisms and found that a 6 prism diopter base down over one eye (or base up over the other eye) allowed her to see the dot in the circle. One image, no vertical displacement. Cool!!!!
We also did some other stuff and I tried out some ideas for physical diplopia practice. And then the three of us started brainstorming and came up with a neat idea for an exercise we want to develop involving black, red, and green felt and Nerf guns (details to come later). It was really fun and inspiring experience all around! I'm more inspired to do my own homework now, and it even made me consider maybe going to optometry school some day. Vision therapy is just so fun!