Primary Open Angle Glaucoma is the most common type of glaucoma accounting for a majority of all glaucoma cases. The condition progresses gradually, when the eye does not drain enough fluid as well as it should (like a clogged drain). As a result, eye pressure builds and starts to damage the optic nerve. Primary Open angle glaucoma is an eye condition that can result in progressive vision loss. While the condition usually begins with slow peripheral vision loss, it can lead to permanent vision loss without treatment. It is often associated with increased intraocular eye pressure. However, it is also possible to have glaucoma in the setting of normal intraocular pressure.