Glaucoma in the far-sighted, who have smaller-than-normal anterior chambers, making physical contact between the iris and trabecular meshwork more likely. Normal-tension glaucoma (also "NTG", "low-tension glaucoma", "normal-pressure glaucoma") is a condition where the optic nerve is damaged although intraocular pressure (IOP) is in the normal range (12-22mm Hg). Individuals with a family history of NTG, those of Japanese ancestry, and those with a history of systemic heart disease are at higher than average risk of developing NTG. The cause of NTG is unknown. Secondary glaucoma refers to any case in which another disease, trauma, drug or procedure causes increased eye pressure,
Glaucoma laser reaches the optimal residual intact layer thickness. In open-angle glaucoma, the typical progression from normal vision to complete blindness takes about 25 years to 70 years without treatment, depending on the method of estimation used. The intraocular pressure can also have an effect, with higher pressures reducing the time until blindness. As of 2010, there were 44.7 million people in the world with open angle glaucoma. The same year, there were 2.8 million people in the United States with open angle glaucoma. By 2020, the prevalence is projected to increase to 58.6 million worldwide and 3.4 million the United