Primary Open Angle Glaucoma
This is the most common form of glaucoma and a worldwide health concern.  It is a chronic and progressive multifactorial optic neuropathy that consists of a loss of optic nerve fibers.  This nerve fiber loss develops in the presence of an open anterior chamber angle.  The loss can be observed with the use of a visual field and measurement of a high IOP.  It manifests by cupping (depression) and forming atrophy on the optic disc.  This type of glaucoma occurs when the eye s drainage canals become clogged over time, the aqueous fluid builds up within the anterior chamber.  The intraocular eye pressure rises because the correct amount of fluid is unable to drain out of the eye.  With open angle glaucoma, the entrances to the drainage canals are clear and working correctly, but the clogging problem occurs inside the drainage canals.