Corneal endothelial changes associated with contact lens wear.

Contact lenses may induce short- and long-term corneal endothelial changes. The endothelial bleb response is a short-term, reversible change noted with contact lens wear. Long-term endothelial changes such as polymegethism (increased variation in cell size) and pleomorphism (a decrease in the frequency of hexagonal cells) have also been detected in polymethylmethacrylate, rigid gas permeable, and daily and extended wear soft contact lens patients. These morphometric changes have also been seen in myopes, aphakes, and corneal transplant recipients. Differences in endothelial morphometry between the central and mid-peripheral regions of the cornea have also been noted in hard lens wearers. The long-term significance of these findings is discussed.