Normal-tension glaucoma: Pathogenesis and genetics

Area of Science:

• Ophthalmology
• Neuroscience
• Genetics

Background:

• Normal-tension glaucoma (NTG) is an optic neuropathy characterized by retinal ganglion cell death and visual field loss, despite normal intraocular pressure (IOP).
• NTG presents a diagnostic and therapeutic challenge as the primary risk factor, elevated IOP, is absent.
• A significant familial predisposition suggests a genetic component in NTG development.

Purpose of the Study:

• To review and synthesize current knowledge on the pathogenesis of normal-tension glaucoma.
• To elucidate the roles of vascular, mechanical, and genetic factors in NTG development.
• To discuss the mechanisms underlying these factors in the progression of NTG.

Main Methods:

• Literature review and synthesis of existing research on normal-tension glaucoma.
• Analysis of studies investigating vascular, biomechanical, and genetic aspects of NTG.
• Discussion of proposed pathogenetic mechanisms based on current evidence.

Main Results:

• Vascular dysregulation, including impaired autoregulation and reduced perfusion pressure, is implicated in NTG.
• Mechanical factors, such as lamina cribrosa properties and cerebrospinal fluid pressure, may contribute to optic nerve damage.
• Genetic predisposition, evidenced by family history in up to 21% of cases, highlights a significant hereditary component.

Conclusions:

• NTG pathogenesis is multifactorial, involving complex interactions between vascular, mechanical, and genetic elements.
• Understanding these components is crucial for developing effective diagnostic and therapeutic strategies for NTG.
• Further research is needed to fully elucidate the interplay of these factors in normal-tension glaucoma.