Definition: Glaucoma is a group of diseases characterized by characteristic optic nerve atrophy and visual field defects in common, with pathologically elevated intraocular pressure being the main risk factor. The level of elevated IOP and the tolerance of the optic nerve to pressure damage are associated with the onset and progression of glaucomatous optic nerve atrophy and visual field defects. Glaucoma is one of the major blinding eye diseases, and it has a genetic predisposition. Glaucoma may occur in 10% to 15% of individuals in the patient’s immediate family.