Cornea
- The cornea forms the anterior one fifth of the fibrous tunic.
- It is transparent, colorless, and avascular. It is oval, the broad end being medial.
- The anterior surface is convex and more curved than the sclera. The posterior surface is concave and forms the anterior boundary of the anterior chamber.
- The margin joins the sclera where the sclera overlaps the cornea.
Structure
- Corneal epithelium lined stratified squamous epithelium.
- Lamina limitans anterior or Bowman’s membrane which is very thin and homogeneous.
- Substantia propria -lamellae of connective tissue with connective tissue corpuscles-the corneal corpuscles that are transparent.
- Lamina elastica or Descemet’s membrane- a thick, elastic homogeneous membrane. This lamina divides at the periphery into three divisions, the anterior part joins the sclera; the middle one gives attachment to the ciliary muscle and posterior division passes to the iris forming the ligamentum pectinatum iridis.
- Endothelium of squamous cells; this after lining the cornea is reflected over the iris.
Note
- All the layers forming the cornea are transparent.
Blood Supply
- Cornea is devoid of blood vessels. It derives nutrition from the superficial plexus of vessels.
Nerve Supply
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Last modified: Monday, 17 October 2011, 6:57 AM