Glaucomas are a group of diseases having in common gradual loss of retinal nerve fibers leading to characteristic excavated appearance (called glaucomatous cupping) of the starting point (head) of the optic nerve (nerve responsible for carrying visual senses from eye to the brain). Neglected, this fell disease gradually devours your field of vision from the periphery and ultimately leads to complete blindness. That is why it is called the ‘silent killer of sight’ and at present, the second leading cause of blindness world-wide. High intra-ocular pressure, as opposed to our previous belief, is no longer considered an essential pre-requisite for occurrence of glaucomatous damage, though lowering eye pressure still remains the mainstay of its treatment.