VISIT EUCLID EMERALD CHINA Myopia Epidemic Euclid Lenses About Us In the News FAQs Find an Eye Doctor For Practitioners Frequently Asked Questions Euclid strives to serve our patients and their parents with the most up-to-date information and assistance with our products. See below for answers to some of the most commonly asked questions about Euclid, orthokeratology and more. Orthokeratology Euclid Lenses Lens Care What is orthokeratology (Ortho-K)? How long will it take to improve my vision? Is there any proof that this process really works? How long do you need to sleep each night for this procedure to work? Why haven’t I heard about Ortho-K before now? I have been myopic for years. What is the difference between Ortho-K and CRT? Contact Us Careers Privacy PolicyRequest to Not Sell Information 45472 Holiday Drive, Suite 7, Sterling, VA 20166 | (800) 477-9396 ©2021 Euclid Systems Corporation. All Rights Reserved. ®/TM denote trademarks of Euclid Systems Corporation and its subsidiaries. All other products names/brand names are trademarks of their respective owners.