Soft contact lens polymers: an evolution.

A review of patents and literature reveals an evolution in materials technologies. The evolution has been driven by an increased understanding of the physiological needs of the cornea, beginning with the first hydrogel lenses developed by Wichterle, followed by a variety of high water hydrogels. Oxygen transmission requirements have been addressed through the use of siloxane and fluorosiloxane containing hydrogels. An important development has been the appreciation of the importance of polymer phase morphology on lens movement on the eye. In parallel with these activities have come the advancements in materials suitable to high volume, low cost production necessary for today's daily disposable lenses.