Glaucoma and blindness?

Glaucoma is the leading cause of blindness and there is no cure (just preventative methods) but if someone is diagnosed with Glaucoma, is it inevitable that they will absolutely lose their sight, or can this be something they have that does not always result in blindness?
If anyone has experience with this, feedback would be appreciated.

Inside the eye, fluid is being made all the time & the excess has to drain away through little drainage holes. If the fluid doesn't drain away fast enough, a build up of pressure occurs. If left untreated, this damages the optic nerve & blind spots in the visual field occur. With time these become permanent & enlarge. This can result in "tunnel vision".

Glaucoma medication is usually very efficient at slowing down the production of fluid within the eye so that the drainage system can cope. If the pressure is lowered to a normal level, no visual field loss will occur.

In the UK adults 0ver 40 are recommended to have an eye examination with an optometrist every 2 years. Tonometry (eg "air puff test") can be perfomed to check pressure and visual field checks to look for blind spots. If a close family member has glaucoma (parent, sibling or child) the NHS pays for the eye examination annually.

glaucoma is the inc. of intraocular pressure which can cause anoxia and atrophy of retina causing progressive visual field defects which eventually lead to blindness.
however when it is well controlled by medications and regular follow up with opthalmologist,blindness will not occur (blindness occur when there is extensive visual defects due to uncontrolled intraocular pressure).
a one who is over 45 years should take opthalmologic examination (tonometry measure eye pressure and visual field) every 6 months for early treatment and good prognosis.
however when the pressure is not controlled by medications ,surgery will be the last resort (filtration) to lower down eye pressure.