It is a pathological increase in intraocular pressure, either due to a lack of aqueous humor drainage or an increase in its production. It produces an optic neuropathy, which is characterized by the progressive loss of the nerve fibers of the optic nerve and changes in its appearance.

Treatment: a) Medical: it is controlled with eye drops, they are placed daily, they reduce the pressure in the eye, they do so by reducing the amount of watery fluid that the eye produces or helping the fluid to better cross the drainage angle. b) Surgery with laser beam: I) Trabeculoplasty: for open-angle glaucoma, a laser beam is used to make the drainage angle work better and thus the aqueous humor flows properly. II) Iridotomy: For closed-angle glaucoma, a laser beam creates a small hole in the iris and thus helps the aqueous humor flow to the drainage hole. c) Surgery in an operating room: I) Trabeculectomy: a small fold is created in the sclera and it will also create a bubble, in the conjunctiva called a filtration blister, it is hidden under the upper eyelid and cannot be seen, the aqueous humor drains from the eye through the crease and into the blister, from there the fluid is absorbed by the tissue around the eye and thus the pressure is lowered. II) Drainage devices for glaucoma: A small drainage tube is implanted in your eye and thus the fluid is sent to a collection area, below the conjunctiva and this is absorbed into the surrounding blood vessels.