What is Primary Open Angle Glaucoma?

Let us understand with an example. Our eyeball is akin to a football. The football needs to be filled with air under pressure, or else it will deflate. Similarly, the eyeball needs to be inflated up to a certain pressure, where it can work well.

This pressure, generally, ranges from 10-21 mmHg. If due for some reason, the pressure inside the eye increases beyond a certain limit, it causes damage to the most sensitive part ie the optic nerve. Now the optic nerve is the structure which takes signals generated in the eyeball to the brain for processing. Glaucoma directly or indirectly affects this structure and only a part/none (in case of blindness) of the signals are carried to the brain. This if untreated can potentially lead to irreversible blindness.