ArticlesNew Technologies to Assess Lens-Mediated Effects of the CorneaFonn, Desmond Dip.Optom., M.Optom., F.A.A.O.; Simpson, Trefford Dip.Optom., M.Sc., Ph.D.; Woods, Jill B.Sc.(Hons.), M.C.Optom.; Woods, Craig B.Sc.(Hons.), M.C.Optom., Ph.D., F.A.A.O. Author Information From the Center for Contact Lens Research, School of Optometry, University of Waterloo, Waterloo, Ontario, Canada. Address correspondence and reprint requests to Mr. D. Fonn, Centre for Contact Lens Research, School of Optometry, University of Waterloo, Waterloo, Ontario, Canada, NQL 3G1. Accepted August 1, 2007. Eye & Contact Lens: Science & Clinical Practice: November 2007 - Volume 33 - Issue 6 Part 2 of 2 - p 364-370 doi: 10.1097/ICL.0b013e318157c98f Buy Metrics Abstract Contact lenses can affect the cornea in a variety of ways. Corneal structure can be altered so that its thickness changes to involve the epithelium and the stroma. As a result, the curvature may be affected, but whether it is the front or the back surface that is affected depends on the type of lens used. If thickness increases sufficiently, corneal transparency may decrease. Contact lenses can also affect cellular structure of all layers of the cornea through mechanical trauma, hypoxia, or toxicity from solutions that are used in association with lenses. More serious complications, such as inflammation and infection, can arise. All these changes can be detected by clinicians using slitlamp biomicroscopes and keratometers if the changes are significant enough. Since the development of computers, optical instruments have become more sophisticated and have enabled the detection of subtle changes but have also facilitated more precise measurement of these conditions along with the ability to capture images of the alterations or defects. This article describes some of the newer techniques and, specifically, the application of optical coherence tomography, confocal microscopy, and esthesiometry. © 2007 Lippincott Williams & Wilkins, Inc.