eyeballs that work together, or don't
I recently had what counted as an intake exam for “vision therapy”, which is a concept i hadn’t really heard of until a few months ago. And it was fascinating to see what bits were being tested and how things shook out in my own vision.
For those who aren’t aware, vision therapy can be brought up in contrast to the outcomes of a standard vision exam. A typical vision exam is generally focused on two things: (1) Can you see an image clearly? Do you need corrective lenses to read a book, or understand road signs? And (2) Are your eyeballs generally healthy? Does your retina look okay? Is there something wrong with the pressure in your eyes? This is fine for a “least-common denominator” approach to care, but there’s a lot more to vision than that!
Just to pull up some of the things i had concerns about or were tested in my intake: Your eyes might not coordinate together and instead one of them just sinks off to the side (often called a “lazy eye”). You might have a hard time switching between looking near and far, creating a delay when you need to (for example) look up from a book or computer screen. You might have a hard time bringing your eyes together or pulling them apart, making it difficult to look at things close up to your face or farther out in the distance. Your eyes might not move exactly the way you want when reading or looking around, creating difficulty when watching a scene in motion or even just moving your eyes across some text. Your brain might just not be processing visual information correctly or completely, and you miss details in a scene or in your peripheral vision.
In my intake (which this office called a “Neuro-Vision Exam” but i think that’s a marketing name this specific clinic uses), i was booked for two hours to run through a gauntlet of tests to see what they could measure. This ranged from things you might expect, like “keep your head in place and follow an object with your eyes as it moves”, to things that felt novel but important, like “use that optometric rig to force your eyes to see double and measure where the image can actually come back together”, to unexpected and awkward things like “with a special tool that toggles between magnification and demagnification, read words off a page”. Each of these tests focused on one particular metric or another, and i learned later that several of the tests overlapped in what they were measuring, and the ones done later were there to check what happens after you’re fatigued. This helps the clinician put together a picture of what your particular difficulties are, so that they can recommend one exercise or another.
So what came out of this gauntlet? A few days after the exam, i had a video-call follow-up with the doctor to talk about the results. She very helpfully explained each category of test and put my results in context of what people around my age are expected to be like. Certain categories, like visual processing, were just fine. What interested me more was the parts where i struggled, whether i knew it in the exam or not:
- My eyes really struggle to change focus between near and far. Not only that, but each eye struggles to a different degree! My left eye was worse than my right, which is a problem because i’m left-handed and left-eye-dominant.
- One significant issue is the ability for my eyes to physically cross together or “converge”, to focus on something close up. This one kinda took me by surprise, since i spend nearly all my time looking at things within a few feet of my face, but it makes some sense: Often, when focusing on fine detail like handwriting or knitting, my eyes will “jitter” for a second as they shake off the stress of focusing up that close. It’s a very strange phenomenon to experience.
- My eyes are slightly misaligned vertically; one is vertically offset naturally and my brain spends conscious effort pulling it into place so i don’t see double all the time.
Those are the ones i could pull from the report and explain readily.
This all adds up to a lot of excess energy spent when doing things like reading or focusing on close details like knitting, which gives me eye strain headaches from time to time. Sometimes the misalignment of my eyes makes itself extremely apparent and they will have a really hard time staying aligned for a few minutes, which is really disorienting. (This all extremely sucks in terms of the career and hobbies i’ve picked out for myself, which all involve reading, focusing on close-up objects, or both!)
So what can be done here? These specific issues aren’t things that can be solved with a new set of glasses; even something like a prism lens (which shifts the image to the side to compensate for a lazy eye) wouldn’t really help with “going cross-eyed” or “switching between near and far focus”. Instead we return to the term i opened the post with: “vision therapy”.
The person i spoke to at the clinic described vision therapy as “physical therapy for the eyes and brain”. While speech therapy gives you practice in forming sounds and words, and physical therapy gives you practice making physical movements to work a healing body part, vision therapy gives you practice exercising your vision so that your brain can learn a better way to see. I’ll know more about the specific exercises when i start next week.
I’m really looking forward to seeing how this works out. I expect it to be rough going at first; we’re specifically going to exercise the things my eyes are bad at! But i think it would be really cool if this resolves some mysterious sources of fatigue or headaches from my life, or if i suddenly get really into reading after i start sucking at it less. I’ll probably post something about the experience on Mastodon or TikTok as it happens, if you’re curious.