Glaucoma is primarily hereditary in nature and can develop in any age group, even though norms suggest it happens in elderly people than younger ones. It is a heterogeneous disorder which leads to progressive loss of mid-peripheral visual functionality and blindness. In simpler words, the aqueous humor is the eye's drainage system. If the drainage system works properly, then fluid drains out and buildup is prevented.

In cases of glaucoma, the drainage system becomes clogged and the intraocular fluid cannot drain, leading to pressure within the eye becoming higher. The high intraocular pressure damages the sensitive optic nerves and results in irreversible loss of vision. The optic nerve connects the eye to the brain and the nerve fibers from the retina. There are millions of nerves that run from the retina to the optic disk. When the fluid pressure increases to a point where it damages the nerve fibers, it begins to die.