Which corneal layer is the thickest?

Which corneal layer is the thickest?

• A. Epithelium
• B. Bowman's membrane
• C. Stroma
• D. Endothelium

Answer: (C)

The layer that is the main volume of the cornea is the thickest. The stroma is made of a dense, orderly mesh of collagen lamellae with keratocytes scattered throughout, and it runs between Bowman's membrane and Descemet's membrane. This organization gives the stroma most of the cornea’s thickness—roughly the majority of how tall the cornea is—while still preserving transparency. In contrast, the outer epithelium is relatively thin but regenerative, Bowman's membrane is a very thin protective sheet, Descemet's membrane is also thin, and the endothelium is a single, tiny cellular layer that helps keep the cornea dehydrated. So the stroma is the thickest layer.

The layer that is the main volume of the cornea is the thickest. The stroma is made of a dense, orderly mesh of collagen lamellae with keratocytes scattered throughout, and it runs between Bowman's membrane and Descemet's membrane. This organization gives the stroma most of the cornea’s thickness—roughly the majority of how tall the cornea is—while still preserving transparency. In contrast, the outer epithelium is relatively thin but regenerative, Bowman's membrane is a very thin protective sheet, Descemet's membrane is also thin, and the endothelium is a single, tiny cellular layer that helps keep the cornea dehydrated. So the stroma is the thickest layer.