Monday, February 23, 2009

Fixation Disparity

From Wikipedia:
Fixation disparity exists when there is a small misalignment of the eyes when viewing with binocular vision. The misalignment may be vertical, horizontal or both. The misalignment (a few minutes of arc) is much smaller than that of strabismus, which prevents binocular vision, although it may reduce a patient's level of stereopsis.
In layman's words, Henry sees the world as a badly tuned TV, especially when it's up close, like when he reads. The images are ever so slightly blurred, because the two images from both eyes are not completely duplicated, therefore just a tiny bit away from each other. He complained about "double vision" two years ago, caused me quite a bit of worry, as I blogged here. At the time my eye doctor couldn't find anything wrong. Either it was the doctor, or Henry being older and more articulate in explaining his problem now, it took two years and two doctors to finally diagnose it.
It's anyone's guess if Henry's fixation disparity is hereditary from my lazy eye. It's a much milder misalignment than strabismus and amblyopia (lazy eye). Only girls in my family inherited the eye problems, with my mom's and mine most serious. But then it's entirely possible the boys are never diagnosed since they can all see very well in exams.
Now Henry has these cool Nike flexible prism glasses that he uses mostly for reading and playing his PSP. Rather cute, isn't he?


zelda said...

I love them! He looks great.

Karin said...

I love that the picture of him is just a bit blurry - to help us imagine what it must be like for Henry!

Those are ultracool glasses!! And I am glad his vision issue isn't preventing him from playing basketball!

Lynn said...

Those are some awesome glasses! Very cool!

Lesley said...

Great specs! When he put them on did he say, "I can see!"

Jennifer said...

Cute specs! Nice choice for Henry. Glad you got a meaningful diagnosis at long last. Hopefully he won't fall asleep with them on while reading, as my younger son does...because then your mornings will be about fishing them out of the crack between the blankets and the wall ;)

My recommendation, after watching Jack's first pair get smashed during an impromptu basketball session in the driveway: invest in a pair of sports goggles. They come with a built-in retainer strap and are pretty much indestructable.

Vivian said...

Jennifer, these are supposed to be indestructable glasses! The lenses are plastic, and the frame is like bendo, you can twist and bend it any direction and it never breaks. For now he only uses them at home where he does most of the reading. I would be very nervous if he has to bring them to school.

kimkim said...

He's adorable. I can see he's a super nice boy as well.