Progression Under the Microscope – Can Basic Science Provide the Link Between Structural and Functional Deterioration? Mechanisms of Progression in Glaucoma

Mechanisms of Progression in Glaucoma Glaucoma is a neurodegenerative disease characterised by progressive loss of retinal ganglion cells (RGCs) over time with associated progressive visual field loss. Elevated intraocular pressure is the strongest risk factor for glaucoma, but the mechanisms by which damage occurs in the disease remain incompletely understood; however, a number of important principles have been established. First, there is strong evidence that the optic nerve head is an important site of injury. Characteristic optic nerve changes are observed in glaucoma and correlate with the pattern of visual field loss. Glaucomatous visual field defects often pertain to the horizontal mid-line and such a pattern would be difficult to explain if the site of injury were predominantly to the RGC bodies in the retina. The arcuate nature of many field defects observed in glaucoma also suggests the optic nerve head as the site of injury. In addition to such clinical evidence, recent basic science studies have pointed to the lamina cribrosa region of the optic nerve as a major site of injury in the disease.