Glaucoma as a neurodegenerative disease.
Helen V Danesh-Meyer1, Leonard A Levin
1Department of Ophthalmology (HVD-M), University of Auckland, Auckland, New Zealand; Department of Ophthalmology (LAL), McGill University, Montreal, Quebec, Canada; and Department of Ophthalmology and Visual Sciences (LAL), Madison, Wisconsin.
Summary
Glaucoma is primarily an optic nerve disease, not a central nervous system (CNS) neurodegenerative disorder. While CNS changes occur, they resemble those in other visual pathway conditions, not primary neurodegeneration.
Area of Science:
- Ophthalmology
- Neuroscience
- Pathology
Background:
- Glaucoma is characterized by progressive optic neuropathy, optic disc changes, and risk factors like age and intraocular pressure.
- Recent findings suggest involvement of central nervous system (CNS) areas beyond the optic nerve in glaucoma.
- This study investigates whether glaucoma shares mechanistic and pathophysiologic features with CNS neurodegenerative diseases.
Purpose of the Study:
- To evaluate the proposition that glaucoma is a neurodegenerative disease of the CNS.
- To compare the pathophysiology of glaucoma with established neurodegenerative and non-neurodegenerative conditions.
- To determine the primary nature of glaucoma's impact on the CNS.
Main Methods:
- Comprehensive literature review focusing on CNS alterations in glaucoma patients.
- Emphasis on neuroimaging and pathological studies.
- Development of a theoretical framework to classify glaucoma relative to neurodegenerative diseases.
Main Results:
- Evidence shows CNS abnormalities in glaucoma, but these mirror changes seen in other proximal visual pathway disorders (e.g., retinal diseases).
- Observed similarities between glaucoma and neurodegenerative conditions also appear in non-neurodegenerative diseases.
- Distal CNS abnormalities in glaucoma are not unique to primary neurodegeneration.
Conclusions:
- Glaucoma is unlikely a primary neurodegenerative disease affecting the CNS.
- Glaucoma is more accurately classified as a primary optic neuropathy.
- Secondary CNS effects are present but do not indicate primary neurodegeneration.
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