Main Menu Back to Corrective Procedures About Eye Care Professionals Corrective Eyewear Prescription Drugs & Supplements Preserving Your Sight Vision Insurance Eye Diagram Glossary   Our Other Sites Bookstore Directory Other Resources Statistics Vision Loss and Blindness Resources Search All Sites Site Map Corrective Procedures - Ortho-K (Orthokeratology) Ortho-K, or Orthokeratology, is a procedure that uses RGP (rigid gas permeable) contact lenses to change the curvature of the cornea to improve its ability to refract light and successfully focus on objects. Unlike regular RGPs, Ortho-K RGPs have a design that can reshape the curvature of the cornea. This method, however, does not produce a permanent result. With conventional Ortho-K, the lenses are worn about eight hours a day. After the cornea has achieved the best shape for optimal vision, the lenses are worn less frequently--perhaps for a few hours every two or three days. If someone starts and then discontinues Ortho-K the corneas will eventually return to their natural state. People choose Ortho-K over refractive surgery because Ortho-K's effects are not permanent. One disadvantage of Ortho-K is that clear vision may fluctuate during the day. Also, Ortho-K may take many months to change a person's vision. A more advanced technique known as "accelerated Ortho-K" takes less time, and may be recommended to achieve a rapid effect. The best candidates for prescription Ortho-K are people of any age who have low amounts of nearsightedness or astigmatism. The goal is to bring the person's vision to at least 20/40. But for some, Ortho-K will provide 20/20 vision. All brands and product names are trademarked or registered trademarks of their respective companies. Copyright of syndicated content belongs to it’s respective author or news organization. Original content (including "look and feel") Copyright © 2001-2006  •  Vision Loss and Blindness Resources  •  All rights reserved.