Updated: Dec 1, 2020
Last week in Part 1 of this series, I provided some background on what Amblyopia ("lazy eye") is and how it's commonly treated by placing a patch over the better seeing eye. We also discussed some benefits as well as the flaws.
The benefits of patching include:
Better visual acuity
Possible improvement in depth perception and binocular vision
The flaws include:
Patching is difficult for the child - emotionally, cognitively, and developmentally (if you don't believe me, try patching one of your eyes for a day, let alone leaving the 'bad eye' to fend for itself).
The success gained from patching (namely, better distance visual acuity measured during your follow up appointments) does not often hold up over time. We showed that by year three, almost half the amblyopic patients do not maintain their improved vision after stopping the eye patch therapy.
In summary, while patching the "good eye" has been most common treatment for amblyopes, it might not always be the best treatment.
Is there a better treatment than patching the eye? If so, what?
I have been an Optometrist for 12 years now.
I have seen hundreds of patients with Amblyopia and I have to admit, I don't think I've prescribed eye patch therapy for more than a handful. Yes you read that correctly. Probably about five.
Certainly most Optometrists reading that would think, "Wow. Aside from prescribing the appropriate corrective lenses, eye patching is the only thing I've prescribed my Amblyopic patients for years, and even decades!"
I realize I'm going against what is considered to be the standard practice, but patients come to my eye clinic seeking different options. And I will do my best to help them with what I know.
The treatment I most commonly use to treat amblyopia is Optometric Vision Therapy.
Optometric Vision Therapy is a treatment in which the patient comes to the office for weekly visits and works one on one with a vision therapist to improve their vision.
How does vision therapy work to improve eyesight in Amblyopia?
The average amblyopic person has more defects in their visual system than simply poor vision out of one eye. They will likely have
brain suppression of one visual channel
Eye tracking problems, especially with the poorer seeing eye
or any combination of the above
So given all of that, we train the person on how to use their two eyes together in harmony instead of conflict.
What it's like to develop Amblyopia
Have you ever been watching a poorly edited video where the video and the audio are out of sync - even just by a fraction of a second?
It could be have an award winning plot with an all star cast and it would still be unpleasant!
This is what it can be like when you have one eye working well while the other doesn't.
"You can't really live like that right?"
You have to adapt somehow. All of that conflict is too disturbing to function with, so you make a change.
Using the out of sync video as an example, you'd cover your ears, or shut your eyes (one of the two).
That is probably going to be the change you'd make to adapt.
This is what the brain does with one of the eyes in Amblyopia.
It actively shuts off one of the channels (i.e. input from one eye). I use this word "active" because it is a process requiring energy, not saving it.
Studies show that suppressing (shutting off a portion of information) in one eye is an active process that requires some effort on part of the brain.
Kind of like raising your hands up to cover your ears to decrease the sound. Or putting your hands over your eyes to hear the audio only.
You have to do a little work to accomplish it.
Until it becomes ingrained.
Vision therapy is designed to stop you from making that inevitable, yet negative adaptation.
Through various procedures to force your eyes in different positions, or activities to help you see through both eyes equally well, we will help to break down that area of vision where your brain has been actively ignoring.
It takes several months and sometimes years to achieve the full benefit.
The duration of vision therapy all depends on how long you've had the condition, whether you have the refractive or strabismic type and whether you really want to work at it to improve your vision.
You have to do the home procedures we give you.
If you are willing to do that, then you could improve your vision at any age.
All without the use of a patch.
You might be wondering if we could help you or one of your children see better.
You may have even tried, or had some success with the patching therapy, but want to find out if there are still areas to work on.
If so, please go here and fill out the form to request a free discovery visit where we can sit down and figure out what steps to take next (if any are needed).
If you want to skip that step, simply go here and fill out the form to request a neuro optometric evaluation and we will call you to schedule the appropriate appointment.
In case you are wondering how we progress through our vision therapy for amblyopia here is the general outline we use.