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Paragon CRT® Contact Lens Clinical Research

More than a decade ago, eye care clinicians initially suggested that orthokeratology, or ortho-k, could potentially be used to control or even halt the progression of myopia. Currently, ortho-k with Paragon CRT® Contact Lenses is not clinically proven to control the long-term progression of myopia. However, ongoing studies and research continue to evaluate effectiveness and improve the safety of Paragon CRT® Contact Lenses. Below are articles and links to current studies and research on myopia and Paragon CRT® Contact Lenses.

“Stabilizing Myopia by Accelerated Reshaping Technique”

SMART, a five-year study initiated in 2009, is currently evaluating the effect of corneal reshaping on myopia progression in 138 patients. At one-year follow-up, subjects wearing corneal reshaping lenses exhibited a mean progression of 0.00D, compared to an average of 0.50D in the control group. 
 The SMART study revealed in 2011 at the Global Specialty Lens Symposium in Las Vegas, Nevada (GSLS), that both the test group and the control group of soft contact lens wearers had the same safety findings.
Source: Daniels K. Consider OrthoK for Myopia Control. Review of Optometry. 2012 July 15.

“Corneal Reshaping and Yearly Observation of Nearsightedness”

The Corneal Reshaping and Yearly Observation of Nearsightedness (CRAYON) study of two years confirmed that corneal reshaping can slow eye growth in myopic children after one year of treatment. Researchers also confirmed that patients who were fitted with corneal reshaping lenses experienced significantly less annual change in axial length and vitreous chamber depth than patients fitted with soft contact lenses.

Source: Walline JJ, Jones LA, Sinnott LT. Corneal reshaping and myopia progression. Br J Ophthalmol. 2009 Sep;93(9):1181-5.

Source and content.

“Children’s Overnight Orthokeratology Investigation”

In 2004, the results from the first report on corneal reshaping (Orthokeratology) for myopia control – the Children’s Overnight Orthokeratology Investigation (COOKI) pilot study – were published. COOKI researchers evaluated refractive error, visual changes and ocular health for six months in myopic children who were fit with overnight corneal reshaping lenses. The researchers determined that overnight corneal reshaping lenses were both a safe and effective treatment for curtailing myopia progression.

Source: Walline JJ, Rah MJ, Jones LA. The Children’s Overnight Orthokeratology Investigation (COOKI) pilot study. Optom Vis Sci. 2004 Jun;81(6):407-13.

Source and content.

“Refractive Error Regulation”

The growing body of science supporting the role of peripheral hyperopic defocus in the growth in axial length in myopia, along with the apparent effectiveness of corneal refractive therapy in modulating the defocus, has stimulated a growing number of practitioners to recommend corneal refractive therapy (CRT) for myopia regulation.

Fortuitously, CRT for myopia results in a zone of curvature in the mid-peripheral cornea, which is shorter in radius than the post-treatment central cornea. This steeper zone causes light to be focused in front of the retina in the mid-periphery, while the central axial light is focused on the fovea. Source and content.

Research Articles


CLS arcitle Today, in every part of the world, lives are touched by myopia. Please read and consider the importance of the topic of myopia and the current data on controlling progression.

Myopia Epidemic and Myopia Progression

NASA Research Provides Basis For Paragon CRT® Contact Lenses

NASA_symbolDuring three Space Shuttle missions from 1993 to 1996, astronauts conducted experiments in the SPACEHAB pressurized research laboratory in the Orbiter’s cargo bay. Through this research, they were able to identify ways to form more permeable materials that allow oxygen to reach the cornea, which are ideal for extended-wear contact lenses.

The results allowed Paragon Vision Sciences to develop an improved process that led to HDS® (Hyperpurified Delivery System) contact lenses. These gas-permeable rigid lenses don’t contain water like soft contacts, are resistant to deposits and less likely to contain bacteria. Since they are rigid, they are easier to handle, retain their shape, and provide better vision. In 2002, the U.S. Food and Drug Administration approved these lenses for continuous wear of up to seven days.

While the HDS® lenses improve vision, the technology was to use these materials to make a contact that could temporarily improve vision after it had been removed from the eye. In other words, it would actually reshape the cornea while the wearer slept.

nasa launch intrThe Paragon CRT® Contact Lenses are the first therapeutic lens design approved by the FDA for overnight use to temporarily reduce nearsightedness. Wearers insert the Paragon CRT® Contact Lenses at night, removing them in the morning. The result should be clear, natural vision lasting all day, eliminating the need for daytime contacts or glasses.

This is a non-surgical alternative for those who want to be free of glasses and contacts without undergoing laser-corrective surgery. In studies, 65 percent of the patients using the Paragon CRT® Contact Lenses achieved 20/20 vision or better.

More than 10,000 eye care practitioners worldwide are now certified to prescribe the lenses for Orthokeratology, with tens of thousands of consumers now enjoying the benefits of this remarkable technology born in space.

For more information on this research, check out the following articles:

Contacts In Space Lead To New Lenses

NASACity Traces Space Back To You

NASA’s Impact in Arizona


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Paragon CRT® Contact Lenses have the unique opportunity to offer alternatives to traditional eye ware and eye surgery.
Give your patients the opportunity to see better without expensive procedures and constant discomfort.