Substantia propria
Encyclopedia
The substantia propria is fibrous, tough, unyielding, and perfectly transparent.
It is composed of about 200 flattened lamellæ (plates of collagen fibrils), superimposed one on another. They are each about 1.5-2.5 micrometres in thickness. These fibrils run at different angles between the limbi
. Fibres of the layers frequently interweave, the anterior lamellæ interweaving more than posterior lamellæ. The fibres of each lamella are parallel with one another, but at right angles to those of adjacent lamellæ. The lamellæ are produced by keratocytes (corneal corpuscles), which occupy about 10% of the substantia propria.
These lamellæ are made up of bundles of modified connective tissue, the fibres of which are directly continuous with those of the sclera
. More collagen fibres run in a temporal-nasal direction than run in the superior-inferior direction.
It is composed of about 200 flattened lamellæ (plates of collagen fibrils), superimposed one on another. They are each about 1.5-2.5 micrometres in thickness. These fibrils run at different angles between the limbi
Corneal limbus
The corneal limbus is the border of the cornea and the sclera . The limbus is a common site for the occurrence of corneal epithelial neoplasm....
. Fibres of the layers frequently interweave, the anterior lamellæ interweaving more than posterior lamellæ. The fibres of each lamella are parallel with one another, but at right angles to those of adjacent lamellæ. The lamellæ are produced by keratocytes (corneal corpuscles), which occupy about 10% of the substantia propria.
These lamellæ are made up of bundles of modified connective tissue, the fibres of which are directly continuous with those of the sclera
Sclera
The sclera , also known as the white or white of the eye, is the opaque , fibrous, protective, outer layer of the eye containing collagen and elastic fiber. In the development of the embryo, the sclera is derived from the neural crest...
. More collagen fibres run in a temporal-nasal direction than run in the superior-inferior direction.
Disorders of stroma
- KeratoconusKeratoconusKeratoconus , is a degenerative disorder of the eye in which structural changes within the cornea cause it to thin and change to a more conical shape than its normal gradual curve....
is a condition caused by disorganised lamellæ, leading to thinned and conical-shaped cornea. - Macular corneal dystrophyMacular corneal dystrophyMacular corneal dystrophy is a rare pathological condition affecting the stroma of cornea. The first signs are usually noticed in the first decade of life, and progress afterwards, with opacities developing in the cornea and attacks of pain...
, associated with the loss of keratan sulfateKeratan sulfateKeratan sulfate , also called keratosulfate, is any of several sulfated glycosaminoglycans that have been found especially in the cornea, cartilage, and bone. It is also synthesized in the central nervous system where it participates both in development and in the glial scar formation following an...
