Video Transcript:
Hi, I'm Charlie Saccarelli, and today we're going to talk about binocular vision. Binocular vision is fascinating. It's so rich, but very few people have a real understanding of it. I would absolutely not even consider myself an expert on binocular vision; though I know enough to work with eyeglasses and understand how eyeglasses and binocular vision work together.
So it all starts with your eyeballs, right? You have two eyeballs, but you only see one thing, right? So what's going on behind the scenes there that's making all of that happen?
One exercise I'd encourage you to do is just kind of a little vision trick. Put two fingers up, one in the front and one in the back. You'll notice that when you look at the front finger, you see two fingers in the back. And when you look at the back finger, you have two fingers in the front. So you always have double vision everywhere except where you are looking - where you're focusing. So if I'm focusing on something, my brain has an expectation that the thing I'm focusing on will be singular.
But everything else in space you kind of see as double all the time. Now when we're talking about a binocular vision disorder, that's going to be, “Hey! My two eyes are trying to look at one thing and they are struggling.” Binocular vision disorders come in so many forms. There's strabismus. There's convergence insufficiency. There are a lot of long ophthalmology names, but ultimately it's your two eyes not seeing one thing.
We can work with that in a number of different ways. One of the big ones, well, one of the interesting things is that after your eyes lock in on something, they try to stay locked unless something affects them so that they become unlocked. So that's kind of how I think about it. It's like if you've ever tried to stitch together two pictures, your eyes do that.
They stitch together the two pictures and then they lock in and stay there. And that's good binocular vision. Binocular vision disorders are basically anything where that lock and maintaining that lock becomes a struggle. So you'll see that a lot in concussions. You'll see that a lot in people who spend a lot of time on computers, because they're kind of focusing at a weird distance.
It exposes itself more after a traumatic brain injury and a concussion. So like, if you look at me real close (which I would encourage you not to), you'll see that one of my eyes is a little bit higher than the other. So basically I am seeing two images at two different heights, but my brain is taking those two images and saying “they're close enough.”
Now after a brain injury, the energy that "hey, close enough" takes a lot of energy. And when your brain is healing, it really exposes that you are taking a lot of your energy and using it to stitch together those two images.
What we do is after you figure out what's causing that lock to unlock, there are a few different ways to address it. One is managing it through prism.
So, prism is basically taking one of the lenses and redirecting the light so that the images that were disparate are now aligned. Another thing is aniseikonia correction, which we talk about in other videos. Aniseikonia is when you have one image that's larger than the other, and another side effect of aniseikonia is called anisometropia.
So what anisometropia is, is that if I have an unequal refraction between my two eyes, my eyes will lock when I look through the centers of the lens. But if I look high through the lens or low through the lens, or left through the lens or right through the lens, my eyes can unlock because the lenses bend light at different angles and remove the lock.
A lot of people will have challenges if they have unequal refractions. One solution for that is contact lenses. Another solution for people who are more averse to contact lenses is the lens that we offer called the Shaw lens. The Shaw Lens designs the lens in such a way that rather than just considering the very centers of the lens, it considers all the places in the lens that you might look through. The lens is designed in such a way that it's maximally efficient for maintaining that vision lock.
Got a question you'd like answered on our "Ask Chadwick" video series?
Just fill out the linked form to send it to us.
Disclaimer: The information provided in this video is for educational purposes only and is based on our experience in optical solutions. We are not medical doctors. Consult with your ophthalmologist, neurologist, or other qualified healthcare professional before making any changes to your treatment plan. The solutions discussed are intended to support, not replace, professional medical advice.