Friday, 15 May 2015

Let's Talk Vision My Little Blind Bat

Let me open your eyes to the world of vision loss.  (Sorry, couldn't resist the grandpa joke) There are a lot of terms thrown about when talking about vision and how they apply to Gideon can be confusing.  Right now Gideon is considered to have a visual impairment.  This means that Gideon has an eye condition that effects how he sees and it can not be fully corrected with glasses or contact lenses.  He will never have 20/20 vision.  He will always see things differently.

As defined by the World Health Organization -

There are 4 levels of visual function, according to the International Classification of Diseases -10 (Update and Revision 2006):
  • normal vision                       
  • moderate visual impairment   
  • severe visual impairment        
  • blindness                        
The American Optometric Association has this definition:

  • 20/30 to 20/60 is considered mild vision loss, or near-normal vision
  • 20/70 to 20/160 is considered moderate visual impairment, or moderate low vision
  • 20/200 to 20/400 is considered severe visual impairment, or severe low vision
  • 20/500 to 20/1,000 is considered profound visual impairment, or profound low vision
  • less than 20/1,000 is considered near-total visual impairment, or near total blindness
  • no light perception is considered total visual impairment, or total blindness
What does this mean for us?  Well after the last cataract surgery I asked the surgeon what she thought Gideon was seeing right now.  She said he was probably seeing 20/400.... maybe 20/300.  That means that Gideon falls right on the upper limits of "Severe Visual Impairment".  He would not even be able to read the big letter E on the top of the chart.  I'm sure that when the cataracts are in his eyes he would fall into the blindness category of "Profound Visual Impairment".  According to the CNIB, in Canada, legal blindness is "worse than or equal to 20/200".  So that makes Gideon legally blind.  To put this into perspective, you can not drive a car if your vision is less than 20/50.

We are still in the early stages.  The surgeon is only taking a guess at what he's seeing and it is possible that his vision can improve down the road.  Once we confirm that the cataracts are gone for good, we can do some more accurate testing.  So far the eye surgeon thinks Gideon's eyes are healing nicely.  Let's all hope that we remain in the clear- literally!

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