Why is it that in some patients w/open angle glaucoma, the treatments aren't successful in slowing nerve damage and preventing substantial field loss?

Frustrating. Some individuals just don't quite respond well enough to conventional treatment strategies. This implies that the iop-reduction philosophy is not always the only factor beneficial to stabilizing the disease. Other factors may be genetic, blood flow, pressure-perfusion imbalances. This is when off label approaches may be attempted: ca2+ channel blockers, statins, ginkgo, limit activity that inc iop.
Protoplasm. Some patients have a week lamina cribrosa ( the structure that anchors the optic nerve in the eye). If a patient has a week structural makeup, the nerve nan stretch and be damaged at what would be considered healthy pressures in other patients.