Hindsight is 20/20
April 23, 2013
By Sarah Vander Schaaff
Sitting in the examining room during my eight-year-old daughter’s recent visit to the optometrist, I had a rare insight into how she sees the world. For the most part, it seemed, as I looked at the chart she viewed, “D’s” looked liked “O’s”. In fact, anytime a letter was difficult for her to see, she called it an “O”.
I was proud of her poise, sitting in the big chair in the darkened room, with instruments set before her eyes, the doctor flipping the slats, asking again, and then again, for her to read a line of letters.
And I was struck my how narrow my own understanding of her eyesight has been. As her mother, I have rushed her to the pediatrician when she complains of an earache, or to the dentist when she’s said a tooth hurt. Those ailments I empathized with. But as someone with good vision, at least for the time, I never really put myself in her shoes when it comes to sight.
A routine exam at her pediatrician’s sent us to the optometrist last year. He prescribed glasses for reading but indicated she may outgrow the astigmatism in one eye. But this spring, a few weeks before what would be her annual exam, my daughter said she was getting headaches. She wanted to see the eye doctor.
And this year’s exam took a lot longer. On top of the astigmatism, the optometrist said she was far-sighted. The glasses, which had seemed like accessories and a sometimes-thing, were to be worn all the time.
And, maybe, he said, an eye patch, if it wasn’t too late.
He gave her another test and seemed relieved to determine that my daughter had the ability to see “three-dimensions” or in stereo, as my friend, a Neuro-ophthalmologist called it.
The window for improving the weak eye’s sight, or rather the brain’s ability to know what the eye is seeing, closes at a certain point, and given we were a bit late to the game, it was fortunate that this was not lost.
My daughter loves wearing glasses and loves the very act of taking care of them. They suit her personality and give her freedom to read and function without headaches. We’re lucky.
But the experience made me think of two themes that Nancy and the group here talk a lot about. First, that intervening early—when we see signs of our children struggling—is important. We strive not to over-react, but in this case, I was very close to under-reacting, or undervaluing the significance of her troubles.
Second, that as much as our children resemble us, they are unique. My daughter may take after me with her red hair and freckles, but she got her will power, and her lousy eyesight from her father. I’d do well to stop assuming she’s a mini-me, and realize that in this, and things to come, she’ll surprise me.
She’ll see the world through her own eyes.
As for what the doctor told me about the importance of seeing in three-dimensions, I asked my friend, Elizabeth Reitman Waller, a Neuro-ophthalmologist, to explain in full.
Dr. Waller says:
“I think what the optom was talking about was amblyopia and development of visual pathways in the brain. When kids have unequal need for prescription glasses in each eye, we worry that the brain will use the eye with the least amount of refractive error and ignore the other one because the image coming in is so blurry. If this happens we call it amblyopia (not the only way you can get amblyopia) and the acuity, or what the eye is capable of seeing decreases. Up until around age 7 this is a very plastic process and we can force the brain to use the eye by correcting the vision with glasses or patching the stronger eye.
After that age it is much more difficult, if not impossible to fix because the brain pathways have been established and can no longer be fixed. Although there is some evidence that there may be some plasticity left in the late teens or early 20s, but not as much.
If someone was born blind, these pathways would never establish so even if the eye defect were fixed (assuming the blindness was eye and not brain related) vision still would not be possible unless we could rewire those pathways too.
Stereo vision is an excellent sign, because you can’t have it without both eyes seeing well and working together.”
Thank you, Dr. Waller.