Monday, October 24, 2011

I see...

We've had a couple of interesting weeks here. Video Boy has inherited his mother's shocking vision - he has myopia (commonly known as short-sightedness or near-sightedness). It occurs when the eyes focus light in front of the retina, leading to unfocussed vision.

Close up is usually OK, but distance vision is pretty fuzzy:

For me, even the couple would have been blurry! I was "medically blind" which meant I got my optometrist fees covered by Medicare (yay!).

So, Video Boy has had glasses for a couple of years now - he has broken one pair and then lost the replacement pair (grrr) and so for a couple of months, his world has looked like the picture on the right...and he was squinting to watch TV, read signs, pretty much all the time.

So, we went off to the optometrist last week to get us some new glasses!

The optometrist is up on all the latest research - with Wombat Girl, we bought a software program with special "lenses" and she had to do a practice session every afternoon to stop her tracking problem, and it worked really well and her vision is near perfect now. So, after testing VB's eyes and found them to be significantly worse, he suggested we try orthokeratology. This was discovered by "accident" - the user wears a form of hard contact lens overnight and wakes up being able to see (after taking them out)!

Basically, the contact lens "reshapes" the cells over the cornea during sleep, effectively flattening the cornea (in much the same way as lasik eye surgery does - I've had this done, which is how I can see now) and allowing clear vision.

The advantages of this system are that the lens is worn during sleep, minimising discomfort during the day; Video Boy can't lose or break his glasses (he could of course lose a contact, but this is much less likely); and the biggie - studies have shown that orthokeratology prevents further deterioration of vision.

So, he had a trial of the lenses last week, but they weren't quite spot on, so this week he had another set. I was worried that he wasn't going to be able to do this - it was quite freaky for him at first and tears did ensue (along with grumbles of "why can't I just wear glasses??"). But he is a real pro at putting them in and taking them out now and I'm reasonably confident that my $1400 will be money well spent.

Video Boy removing his contacts with a little suction cup thingy...

As all good homeschoolers do, we used this as an opportunity to research the anatomy of the eye! I have a fabulous book from my science teaching days called Anatomy Colouring In - it is the bomb of human anatomy!  It really helps to understand the nitty gritty of such about any part of the human body you care to name. We did the eye sheet:

We also watched an episode of Scope called Things That See (available from iTunes) and also the omnipresent Bill Nye the Science Guy:

Then it was off to Exploratorium, where you can learn more about eyes and that has the BEST instructions for cow eye dissection! So if you are brave, watch the video. If you are even braver, try it at home!

It had to be done. I called the local abbatoir and ordered some cows eyes. Got some local homeschoolers together, and in the name of science, very carefully and respectfully dissected cows eyes (don't look if you're squeamish):

Note the "glow" of the reflected flash in the tapetum lucidum,
 which allows the cow to see at night (and how we go spotlighting)
Wombat Girl doesn't look impressed with her Mum's surgical skills!
Eye with muscles still attached compared
to one where they have been removed
Note the (severed) optic nerve -
which is technically an extension of the brain
Great work Video Boy!
The text underneath the lens reads "not for the faint-hearted"!!!
Corneal half, iris, retinal half
Have a look at Video Boy's face!
View through the cornea - note the horizontal cut
where we extracted the liquid aqueous humour

I also found the best images of eyes on the web! And while I'm at it, some fabulous optical illusions - our eyes playing tricks on us!

And the good news for Video Boy is that playing video games and reading lots does not cause myopia - nah, it's the staying inside that does it! Actually the optometrist recommended he spend more time outdoors which is why we chuck him off the computer periodically and say "go jump on the trampoline".

My Mum also joined in the theme, and had a cataract operation last week, where they removed the lens and put in an artificial one.

And finally, I also found the best images of eyes on the web! And some fabulous optical illusions - our eyes playing tricks on us! Finally, can you name the animal the images of the eyes come from below? Answers in the comments section soon!


  1. I'm not too squeamish about the science.... but the smell! Oh, the smell. I can still smell the formaldehyde from highschool. oof.

    And I'm so happy that reading (on and offline) isn't detrimental to his visual health! What a relief.

  2. Oh, but Stephanie, that was why we went to the abattoir - fresh eyes, no formaldehyde. There really wasn't any odour at all (not even butcher smell).

  3. There is something to be said for virtual dissections.

    I'll have to look into the contact lens thing...

  4. Ingi, I love it! You had mentioned eye dissection after our rat dissection,
    now I am really keen! Great job listing all those resources - going to put this on the list to do right now.

    Fascinating about the contact lenses. Eyesight is fine here, but November's teeth are a little screwy so are doing the lens equivalent for teeth - using mouth-guards at night and 1 hour a day - to fix her jaw and palette shape now rather than do extractions (eek) and braces later.

    Nothing like some real-life adventures to inspire learning ; )
    Like the new photo by the way!


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