What does the corneal stroma consist of?

What does the corneal stroma consist of?

• A. Endothelial cells and keratocytes
• B. Collagen fibers and flattened fibroblast-like cells (keratinocytes) for general repair and maintenance; they are superimposed like a book pages
• C. Blood vessels and pigment
• D. Epithelial cells

Answer: (B)

The corneal stroma is defined by its organized network of collagen fibers arranged in layered sheets, called lamellae, with flattened fibroblast-like cells known as keratocytes scattered between them. This combination—dense, orderly collagen and resident keratocytes within a hydrated extracellular matrix—provides both the transparency and mechanical strength essential for vision. The image of lamellae stacked like book pages captures how the fibers are aligned in a precise, laminar fashion to minimize light scattering while preserving rigidity. A few nearby structures aren’t part of the stroma’s composition. Endothelial cells line the inner surface of the cornea, not the stroma. The stroma is avascular and contains no pigment, so blood vessels and pigment cells aren’t components of this layer. The outermost epithelial cells belong to the corneal surface, not the stroma, which is why they don’t describe its makeup. The key cellular component you’ll find in the stroma are keratocytes, the flattened fibroblast-like cells responsible for maintaining and repairing the extracellular matrix.

The corneal stroma is defined by its organized network of collagen fibers arranged in layered sheets, called lamellae, with flattened fibroblast-like cells known as keratocytes scattered between them. This combination—dense, orderly collagen and resident keratocytes within a hydrated extracellular matrix—provides both the transparency and mechanical strength essential for vision. The image of lamellae stacked like book pages captures how the fibers are aligned in a precise, laminar fashion to minimize light scattering while preserving rigidity.

A few nearby structures aren’t part of the stroma’s composition. Endothelial cells line the inner surface of the cornea, not the stroma. The stroma is avascular and contains no pigment, so blood vessels and pigment cells aren’t components of this layer. The outermost epithelial cells belong to the corneal surface, not the stroma, which is why they don’t describe its makeup. The key cellular component you’ll find in the stroma are keratocytes, the flattened fibroblast-like cells responsible for maintaining and repairing the extracellular matrix.