Glaucoma: the retina and beyond

Abstract

Over 60 million people worldwide are diagnosed with glaucomatous optic neuropathy, which is estimated to be responsible for 8.4 million cases of irreversible blindness globally. Glaucoma is associated with characteristic damage to the optic nerve and patterns of visual field loss which principally involves the loss of retinal ganglion cells (RGCs). At present, intraocular pressure (IOP) presents the only modifiable risk factor for glaucoma, although RGC and vision loss can continue in patients despite well-controlled IOP. This, coupled with the present inability to diagnose glaucoma until relatively late in the disease process, has led to intense investigations towards the development of novel techniques for the early diagnosis of disease. This review outlines our current understanding of the potential mechanisms underlying RGC and axonal loss in glaucoma. Similarities between glaucoma and other neurodegenerative diseases of the central nervous system are drawn before an overview of recent developments in techniques for monitoring RGC health is provided, including recent progress towards the development of RGC specific contrast agents. The review concludes by discussing techniques to assess glaucomatous changes in the brain using MRI and the clinical relevance of glaucomatous-associated changes in the visual centres of the brain.

Ocular indicators of Alzheimer’s: exploring disease in the retina

“…However, apparent differences between glaucoma and the ocular manifestations of AD challenge such a notion. While glaucoma shows optic disc cupping accompanied by a specific pattern of loss in the optic nerve and GCL [3, 41], the ocular findings in AD have overwhelmingly indicated damage to the NFL and GCL along with hallmark molecular signs in peripheral retinal regions [20–22, 81, 107, 113, 163]. Since evidence linking the two diseases remains controversial, further research would be warranted before claims of common etiology could be made about these diseases.…”

Blood Pressure Elevation Associated with Topical Prostaglandin F2α Analogs: An Analysis of the Different Spontaneous Adverse Event Report Databases

“…Based on the status of the internal drainage system, this condition is divided into two major subtypes i.e., open angle and angle closure. 1) Reducing intraocular pressure (IOP) is one of the best ways to prevent the development of glaucoma, although there is a kind of open angle glaucoma in which optic neuropathy occurs without IOP exceeding the normal range. The approximate number of glaucoma patients was 60.5 million in 2010 and is estimated to increase to 79.6 million by 2020.…”

Stem cell therapies for retinal diseases: recapitulating development to replace degenerated cells

“…As with other parts of the central nervous system, the adult mammalian retina has limited regenerative capacity, and thus NR or RPE cell death can lead to irreversible vision loss. Retinal degenerative diseases, such as glaucoma, retinitis pigmentosa (RP) and age-related macular degeneration (AMD), are characterized by the early loss of specific cell types: retinal ganglion cells (RGCs), photoreceptors or RPE cells, respectively (Davis et al, 2016;De Jong, 2006;Ferrari et al, 2011). Eventually, this leads to a common pathophysiology: the dysfunction of light-sensing photoreceptors, which results in untreatable blindness (Berson, 1993;De Jong, 2006;Quigley, 1993).…”