Orthokeratology and contact lenses

Hard contact lenses fitting to change the shape of the cornea deals orthokeratology. This method is used for short-sighted clients, using hard contact lenses. The contacts are worn at night, when they should have slightly modified the curvature of the cornea, during the day the clients are initially corrected by the normal way (lenses) until the shape of the cornea is correct. Conversion of the cornea is achieved by using special type of contact lenses, having inverted design. This process is reversible, which is a big advantage compared to alternative operational methods. His asset is also painless.

It might seem that this is a novelty. As in many other industries, however, first attempts in this field have made the old Chinese, who know that compression can alleviate symptoms of eye myopia. In modern history, carried out the first compression ortokeratologickou J.B.E. Kalt, in 1888. Improving the efficiency of this method goes hand in hand with the development of equipment, describing the topography of the anterior segment.

On the effect of exposure orthokeratology lenses involving several factors. They are thinning of the cornea, anterior chamber depth reduction, corneal flattening and bending. The case studies explain the effect of orthokeratology by changing the thickness of epithelium. Corneal epithelium is thiner in center and thicker in the middle periphery. This is due to positive pressure at the top of the lens and cornea due to the negative pressure of the lacrimal lake. After the first night, when they are applied to these special lenses, the corrected 10% of myopia and refraction becomes stable after 10 nights. Application overnight is quite safe, side effects were observed.

This method can be expanded in the last ten years, which is related to the development of new materials with higher permeability, which allows lenses worn during sleep. In some countries, the company created to deal with this issue. Orthokeratology is especially popular in Great Britain, USA, France, China and Japan.