By far, the most common type of Glaucoma is called Primary Open Angle Glaucoma (POAG). Primary Open Angle Glaucoma is also called Chronic Open Glaucoma and accounts for 19% of blindness in Afro-Americans and 6% in Caucasians (http://www.glaucoma.org/learn/glaucoma_facts.html)
Most patients with Primary Open Angle Glaucoma have an increase in Intraocular Pressure (IOP) upon routine measurement, called Tonometry. This increased Intraocular Pressure (IOP) results from either too much Aqueous Humor being produced or too little being drained as mentioned earlier. This fluid buildup within the closed space of the inside of the eye causes the pressure to rise. This elevation in pressure (IOP) causes the blood flow in the Optic Nerve to become decreased, depriving it of oxygen and nutrients. If left untreated this can result in permanent changes and damage to the optic nerve resulting in vision loss. The optic nerve is the connection between the retina and the brain and is responsible for communicating visual images. Once the optic nerve is damaged, it is not able to carry visual images, resulting in vision loss. This is why it is so important to monitor, detect and control Intraocular Pressure (IOP). If left untreated, an elevated Intraocular Pressure (IOP) may, over time, cause slow progressive, permanent damage to the Optic Nerve that can result in blindness.
A less common, but important type of Glaucoma is Angle Closure Glaucoma or Narrow Angle Glaucoma.
