title: Twenty-five years of contact lenses: the impact on the cornea and ophthalmic practice.
abstract: OBJECTIVE
  The history of contact lenses has occurred in the latter half of the 20th century. In particular, events in the 1970s through the 1980s related to the invention of soft, hydrogel contact lenses have revolutionized the contact lens industry and the eye care attached to it. This article recounts that history from the perspective of market forces, inventions, and discoveries about the physiologic functioning of the cornea.
  
  
  METHODS
  The relevant literature is critically reviewed.
  
  
  RESULTS
  Discoveries about the oxygen needs of the cornea and consumer pressure for clear, comfortable, around-the-clock vision have resulted in a history of rigid gas permeable and soft lenses that leads to today's contact lens picture. The short-term and long-term effects of chronic hypoxia and the levels of lens oxygen transmissibility necessary to avoid them have been well-described. The advent of the soft lens, followed by the "human experiment" with initial extended-wear modalities, led to the advent of the disposable soft contact lens.
  
  
  CONCLUSIONS
  In the past 25 years, the development and wide acceptance of soft contact lenses have revolutionized the management of refractive error and corneal diseases.
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, 60612, USA.
authors.forename: T T
authors.initials: TT
authors.lastname: McMahon
authors.forename: K
authors.initials: K
authors.lastname: Zadnik
mesh_terms: D003261:Contact Lenses / Q000266:history* / Q000592:standards / Q000639:trends; D003316:Corneal Diseases / Q000266:history / Q000628:therapy; D003604:Czechoslovakia; D049673:History, 20th Century; D006801:Humans; D009885:Ophthalmology / Q000266:history*; D012030:Refractive Errors / Q000266:history / Q000628:therapy