Open angle glaucoma 30 percent optic nerve damage. 58 years old. How many years before damage would be seen. Dr did not screen yearly w/annual exam.

Best to take multipl. Field exams, and look at the severity of the defect and the rate of progression with treatment (plotted against the estimated number of years to live) and you can get an idea of how long before very advanced damage can lead to actual real life vision changes vs. Merely changes on a test that are not seen in real life.
Glaucoma. Assuming you will be treated with pressure lowering medications, statistically, there is a 27% chance of becoming legally blind in one eye, and 9% in both eyes withing 20 years. With 30% nerve damage, this number is reduced, but it depends whether the peripheral or ventral fibers are affected as to now you perceive any progressive advancement of the visual loss.