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Schlemm's canal: the outflow 'vessel'
Katarzyna Lewczuk1, Joanna Jabłońska1, Joanna Konopińska2
1Department of Ophthalmology, Military Institute of Medicine, Warsaw, Poland.
Acta Ophthalmologica
|September 14, 2021
Summary
Glaucoma increases eye's aqueous humor outflow resistance, raising intraocular pressure. This review details Schlemm's canal and aqueous humor pathways, crucial for understanding glaucoma and assessing drainage with channelography.
Area of Science:
- Ophthalmology
- Anatomy
- Physiology
Background:
- Glaucoma affects 60 million worldwide, characterized by elevated intraocular pressure (IOP).
- Increased resistance to aqueous humor (AH) outflow in the juxtacanalicular meshwork is a primary cause of elevated IOP in glaucoma.
- Understanding the conventional aqueous humor drainage pathway is critical for glaucoma research.
Purpose of the Study:
- To comprehensively review the morphology of Schlemm's canal (SC) and aqueous humor pathways.
- To discuss the role of SC in glaucoma development and outflow resistance.
- To present channelography as a method for assessing the conventional drainage pathway.
Main Methods:
- Review of existing literature on ocular anatomy and physiology related to aqueous humor outflow.
- Detailed description of the aqueous humor pathway from the anterior chamber to episcleral veins.
- Introduction and explanation of channelography for evaluating collector and aqueous veins.
Main Results:
- The review delineates the complete path of aqueous humor flow through the trabecular meshwork, collector channels, and into episcleral veins.
- It highlights the significance of Schlemm's canal in regulating outflow resistance and its implication in glaucoma.
- Channelography is identified as a precise technique for assessing the conventional drainage pathway and identifying specific venous structures.
Conclusions:
- The morphology of Schlemm's canal and associated pathways are integral to maintaining normal intraocular pressure.
- Disruptions in these pathways, particularly at the juxtacanalicular meshwork, contribute significantly to glaucoma pathogenesis.
- Channelography offers a valuable tool for in-vivo assessment of the conventional outflow pathway, aiding in glaucoma diagnosis and management.
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