Briefly, glaucoma has to do with the dying of optic nerves behind the eyes when internal pressure builds up because it can't drain off fluid normally. You can read it here in details: Glaucoma
My left eye has lost about 10% of its vision. Treatment involves the application of eye-drops. I always feel like I can't see too well and something is blocking my sight, and feel the need to rub my eye. I think I have to get use to this imperfect sight.
What do you see when you have glaucoma?
This is what you see with normal vision:
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This is what you see with advance glaucoma:
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One dear lady with advance glaucoma in both eyes described her sight like this, "It is like seeing the world through cob-webs!"
What about the other eye problems and diseases? What would you see if you have macular degeneration, cataracts, retinal degeneration, floaters or colour blindness?
Shudder, shudder ... check out this link, there is a tool to simulate these conditions for you:
http://www.webmd.com/eye-health/slide-vision-test
May God bless your sight, I will SEE YOU again!