The death of retinal ganglion cells (RGCs) is what leads to glaucoma-induced vision loss. The more RGCs that die, the worse vision loss becomes. As RGCs are part of the central nervous system, they do not regenerate once lost. However, death is the final step in the process. If an eye care professional can identify when RGCs begin to stop working properly due to increased intraocular pressure, treatment can begin at this early stage, thus slowing or preventing cell death and vision loss.