The name glaucoma is actually used to describe not just one eye condition but a group of eye conditions that affect your vision. What they all have in common is that in each case there's damage to the optic nerve - the nerve at the back of the eye that sends information from your eye to your brain.
What usually happens is that the drainage tubes within the eye become slightly blocked. This stops the natural eye fluid from draining away properly.
When this fluid can’t fully drain, pressure inside the eye, known as intraocular pressure (IOP) builds up and stops the optic nerve from getting enough blood. As the nerve becomes damaged, the eye becomes less sensitive to light.
Glaucoma often affects both eyes but one eye may be more quickly than the other.
If it isn’t treated, glaucoma can have serious consequences and even cause blindness. But provided it’s diagnosed and treated early enough, further damage to your vision can be prevented.
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