Your eye functions similar to an old-style camera. In the camera, the light comes in through the shutter, is focused by the lens, falls onto the film and then it’s processed. In your eye, light comes in through the cornea and pupil. It is focused by the lens, falling onto the film in the eye (the retina) and then goes, via the optic nerve (the nerve of sight), to the brain (the processor) for developing.
For people living with glaucoma, there has been damage done to the optic nerve, causing some of the images captured by the eye to not reach the brain, which can result in progressive vision loss.
This damage that is done to the optic nerve can be caused by injury or by poor blood flow. In most cases, the damage which is done to the optic nerve is from pressure within the eye.
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