Other factors which may contribute to glaucoma are nerve cell death and reduced blood flow. Most glaucoma patients suffer from this type. Usually starting in one eye and progressing to the other, this type of glaucoma is brought about when the fluid drainage angle within the eye is open but the drainage channels are closed. This creates a fluid build-up and pressure on the optic nerve increases. Over time, the nerves at the back of the eye are exposed to increasing pressure.
Peripheral vision is lost first.
By the time all peripheral vision is lost, damage is irreversible. Tunnel vision remains after the peripheral vision is lost, with the patient only able to see what is directly ahead. If not treated, and the pressure not reduced, this condition can damage the eye until complete vision is lost. Although open-angle glaucoma is not caused by one single factor, several elements are known to contribute to risk for the disease. With chronic open-angle glaucoma, the symptoms may be so mild that none are noticed until irreversible damage has been done.