الفهرس 
Anatomy of CorneaOnly 14 pages are availabe for public view
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Abstract
Keratoconus is a progressive non-inflammatory, degenerative disease that affects the integrity of the collagen matrix within the corneal stroma. Its hallmark is the formation of a localized cone-shaped ectasia, and accompanied by thinning of the stroma in the area of the cone. This might cause irregular astigmatism and a steep corneal curvature.
Until the last decade of the 20th century, the only surgical option for patients with keratoconus was keratoplasty procedures. However, nowadays there are numerous procedures that tend to stop the progression of the disease and improve the patient’s visual function, which includes corneal collagen crosslinking, Intra-corneal stromal implants and different modalities of keratoplasty procedures, including penetrating keratoplasty and deep anterior lamellar keratoplasty.
Corneal Cross-linking, the term used to describe the formation of chemical bridges following a chemical reaction between proteins and other molecules. It was first performed by a group at the Dresden Technical University where they used Vitamin B2 (Riboflavin) and ultraviolet A to increase the formation of cross links between the collagen fibers in the corneal stroma, producing a rigid effect capable of halting the progression of the ectasia.
This will generate various effects in the cornea, such as increased stiffness, changes in biomechanical and bioelastic behavior of the tissue and different visual, refractive and topographic changes. Two techniques are described for this procedure the (Epi-off) technique; involving mechanical removal of the corneal epithelium and the less invasive (Epi-on); with intact corneal epithelium.