Moderately elevated eye pressure may be tolerated for years, without harming the optic nerve; all that may be required is periodic careful eye examination. If the eye pressure reaches a level where damage is more likely or already apparent, treatment to lower the pressure should be considered.
The optic nerve damage and loss of vision caused by glaucoma are irreversible. The only intervention known to reduce the risk and rate of glaucoma progression is lowering of the eye pressure. Lower and stable levels of pressure reduce risk progressively but can sometimes be difficult to achieve. The purpose of treatment is to prevent or slow down further damage in order to avoid significant visual loss during your lifetime.
Individuals respond differently to treatment and if one type is ineffective or not tolerated, another may work well. Once started, treatment and regular monitoring are usually lifelong to ensure that your glaucoma remains under control. If the optic nerve or visual field appear to deteriorate or to be at greater risk, additional treatment may be needed to lower the eye pressure further. Occasionally, glaucoma continues to change despite pressure being low.