Contact lens wear and the corneal endothelium.

Contact lenses produce transient and permanent effects on the corneal endothelium in relationship to the lens oxygen transmissibility and how the contact lenses are worn. There is concern, as well as growing evidence, that contact lens-induced corneal endothelial pleomorphism causes a reduction in the endothelial functional capacity. This, in turn, may place an eye at risk for uncontrolled corneal swelling if the eye is under sufficient environmental or surgical stress. Use of lens materials and designs which promote high oxygen transmissibility, and patient wear of lenses during waking hours only, are ways to slow the development of permanent corneal endothelial pleomorphism.