الفهرس 
Contact Lens MaterialsOnly 14 pages are availabe for public view
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Abstract
All CLs act as a potential barrier to oxygen reaching the cornea and the ability of a lens to transmit oxygen is a major factor in determining its clinical success. The optimal CL material is one that meets or exceeds the oxygen requirements of the cornea, provides adequate in-eye wetting, and requires minimal patient care.
Contact lenses can be manufactured by lathe cutting, spin casting and cast molding. The manufacturing technology used affect the mechanical properties, surface finish and clinical performance of the lenses.
Today, many options are available for the correction of presbyopia. New technologies continuously appear to offer better ideas and designs to meet the visual demands of the presbyopic population.
Improved lens reproducibility and expanded parameter options have contributed to increased success in prescribing toric CLs for astigmatic patients. There are two types of toric lenses: soft and RGP toric.
When a keratoconic patient is no longer able to obtain good visual acuity as a result of increasing levels of irregular astigmatism and higher-order aberrations, CLs will be required to provide a new anterior surface to the eye. CLs are considered when vision is not correctable by spectacles and patients become symptomatic. There are many lens designs for keratoconus and it is difficult to predict which design will be suitable for any particular patient.
Practitioners have used aspheric lenses for a long time to increase the depth of focus of the eye. More recently, manufacturers have designed aspheric CLs to correct spherical aberration of the lens and/or the eye.
Orthokeratology is a temporary reduction in myopia by the programmed application of rigid CLs. Using slowly flattening lens fitting.
Contact lenses provide millions of people with glasses-free vision correction. However, since their inception, CLs have also served as a way to therapeutically manage anterior segment disorders.
The most common uses of Colored or tinted lenses are for cosmetic purposes, along with vision correction, but a prosthetic CL is a painted CL used to improve the appearance of a disfigured eye to help correct the vision of a poorly functioning eye.