corneal epithelium


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Related to corneal epithelium: Corneal endothelium, Corneal stroma, Bowman's membrane

corneal epithelium

The thin, layered, outer ‘skin’ of the cornea. Advances in cell culture techniques have made it possible to grow complete sheets of viable corneal epithelium from a tiny sample taken from the edge of the patient's cornea. This is an important advance in the management of conditions featuring corneal epithelial disorders.

corneal epithelium 

The outermost layer of the cornea consisting of stratified epithelium mounted on a basement membrane. It is made up of various types of cells; next to the basement membrane are the basal cells (columnar in shape), then two or three rows of wing cells and near the surface are two or three layers of thin surface squamous cells (or superficial cells). The outer surfaces of the squamous cells have projections (called microvilli and microplicae), which extend into the mucin layer of the precorneal tear film and are presumed to help retain the tear film. The epithelium in humans has a thickness of about 51 μm. Some dendritic cells of mesodermal origin are also normally present. Epithelial stem cells are located at the limbus; they give rise to the basal cells. The corneal epithelium receives its innervation from the conjunctival and the stromal nerves. The life cycle of epithelial cells is about a week (Fig. C20). See Langerhans' cell; epikeratoplasty; mitosis; pachometer; palisades of Vogt.
Fig. C20 Diagram showing the various layers of the corneal epitheliumenlarge picture
Fig. C20 Diagram showing the various layers of the corneal epithelium
References in periodicals archive ?
It is widely accepted that in humans, the stem cells of the corneal epithelium are located only in the limbus region, segregated in specific structures known as limbal crypts in the palisades of Vogt [1, 25-28].
Although it recovered within a week or so, the vulnerable adhesion of the corneal epithelium became clear.
The drug intervention was implemented immediately after the excochleation of corneal epithelium. Normal saline was injected intraperitoneally to the mice in the control and diabetic groups based on 1 ml/100 g, and SA injection (Tonghua Guhong Pharmacy, Meihekou, China) to the mice in the treatment group based on 1 ml/100 g.
For example, the density of nerve fibers in the rabbit corneal epithelium was estimated as 300-600 times and 20-40 times compared to that of skin and tooth pulp, respectively [2].
With respect to its expression in ocular tissues, studies in murine eyes have reported constitutive expression in the corneal epithelium and several retinal layers [15].
Corneal epithelium serves to protect the underlying corneal stroma, posterior eye structures, and tissues against UVB damage by absorbing a substantial amount of UV radiation.
There is an extremely complex relationship between the basal cell layer of corneal epithelium, basement membrane and superficial layers of the underlying stroma (Moore 2003).
GeneSoft is a colourless and transparent ophthalmic solution containing a derivative of recombinant human epidermal growth factor (rhEGF) for topical use which enhances the healing of cornea wounds by promoting corneal epithelium regeneration.
The integrity of the squamous, nonkeratinized stratified corneal epithelium is essential for adequate light refraction and to achieve good vision.
After birth and during the life time, it is also expressed in the eye (playing an important role in the control of corneal epithelium proliferation), cerebellum, and pancreas (regulates alfa-cells activity) [3, 6].
Immunolocalization using a pan-laminin antibody revealed that at 60 hpf, laminin was found both in the lens capsule as well as the basement membrane underlying the developing corneal epithelium (Figures 4(a) and 4(b)).
The morphology of the corneal epithelium and stroma was compared between a normal cornea (Figure 1(a): the center and Figure 1(c): the limbus) and the diabetic cornea of 12-week-old db/db mice (Figure 1(b): the center and Figure 1(d): the limbus) with hematoxylin and eosin staining, and the swelling and stratification of the diabetic corneal epithelium, both in the center (Figure 1(b)) and limbus (Figure 1(d)), were noted compared with that of the normal corneas (Figures 1(a) and 1(c)).

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