What comes next is rather a mystery, even today. What we believe happens is a mismatch of fluid being pumped into your eye and the amount of fluid exiting the drain (called the angle).
By placing a special mirrored contact lens on your eye, the drain may be visualized. In POAG, the drain appears to be open. However, on a microscopic level, the drain may be filled with debris, which may cause the fluid to build up in your eye (like your kitchen sink filling up with water).
Alternatively, your faucet may be working too well and overwhelming the ability of the drain to get rid of the fluid fast enough. Unlike your kitchen sink, which can spill over on the floor, the eye is contained and the fluid just builds up in the eye. The result of this is that the fluid starts to compress the other parts of the eye.
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