I always suspected that the pressure issues in glaucoma were secondary, as is evidenced by “normal pressure” glaucoma, where the same damage to the retina is seen without elevated pressure.

The retina, a part of the brain, is one of the most chemically-active tissues, having to absorb concentrated light and then process it. It makes sense that it would be particularly vulnerable to different metabolic stressors. Since metabolic stressors can be different, the type of damage could be different.  I believe this applies to glaucoma and macular degeneration. Just as with high- and low-pressure glaucoma, there is wet and dry macular degeneration. Do these labels/categories really apply or are they all variants of an underlying root cause? We could also include cataracts, where the damage from the sun affects the lens separately from the retina.  There is good data on the mechanism of cataract and potential modulators/remedies.

Back to glaucoma, below are articles that support this idea and suggest that a core nutrient, niacin, may have a role in its prevention and even possible reversal.