Introduction: Elevated intraocular pressure(IOP) is a
major risk factor for the development of glaucomatous optic neuropathy. Lowering IOP has been shown to be a
beneficial form of therapy for
patients with Primary Open Angle Glaucoma(POAG)
Methods: Review and
meta-analysis of completed and
ongoing epidemiologic studies analyizing the relationship between IOP and POAG
Results: Several large scale epidemiologic
studies have shown that the relationship between IOP and the prevalence of POAG
is positive and continuous without an inflection point, even when IOP is in the
normal range. Diurnal
fluctuation in IOP makes a single IOP measurement a poor screening parameter
for POAG. Glaucoma treatment
studies have shown that IOP lowering in eyes with known glaucomatous visual
field loss and optic nerve damage decreases the rate of disease
progression. Large diurnal
variation in IOP may be an independent risk factor for glaucomatous visual
field progression.
Conclusions: While the level of IOP is often not
critical in making the diagnosis of open angle glaucoma, it remains the only
proven modifiable variable in the treatment of the disease. Treatment modalities that lower IOP and
minimize peak and trough fluctuations in IOP are most likely to halt the
progression of glaucomatous optic neuropathy.