What is glaucoma?  

Glaucoma is a progressive disease of the optic nerve which, if untreated, can lead to a narrowing of the vision field, deterioration of the optic nerve and significant, and even permanent, loss of vision. It has no symptoms and therefore it is called "the silent thief" or "silent killer" of the vision.

How frequent does glaucoma occur? 

Glaucoma is the second cause of blindness in the world. Previous studies have shown that approximately 2-3% of the population older than 40 years suffer from some type of glaucoma, but is assumed that 50% of cases remain unrecognized.  The results of prospective study show that in 2010 the number of people with glaucoma worldwide was 65.8 million, and predictions are that by 2020 that number will be 78.6 million, while in 2040 could grow to 111.8 million. Currently, more than 6 million people in the world are blind as a consequence of glaucoma.