Ongoing studies and research continue to evaluate long-term effectiveness and improve the safety of Paragon CRT® Contact Lenses. At this time, orthokeratolgy with Paragon CRT® Contact Lenses is not clinically proven to control the long-term progression of myopia. However, more than a decade ago eye care clinicians initially suggested that orthokertology, or ortho-k, lenses could potentially be used to manage or even halt the progression of nearsightedness (myopia) and clinical research continues to this day.1
“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.
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.
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.
For More Information On Orthokeratology And Myopia Research, Check Out These Articles:
The Contact Solution NASA Space Shuttle Missions: The Secret to Overnight Success
While it may sound like science fiction, the technology that makes Paragon CRT® Contact Lenses possible is here today thanks to some out-of-this-world research. In 1993 NASA joined forces with Paragon Vision Sciences of Mesa, Arizona, to study the production of polymers in the weightlessness of space. Free from the effects of gravity, scientists hoped their experiments would lead to a process that could improve the purity of premium-performance polymers necessary for making contact lenses. By unleashing contact lens materials in microgravity, they believed they could better understand how polymers — the molecules that make up plastics — are formed.
During three Space Shuttle missions from 1993 to 1996, astronauts conducted experiments in the SPACEHAB pressurized research laboratory as it rested 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.
Back on Earth, the results enabled Paragon Vision Sciences to develop an improved synthesis process that first led to HDS® (Hyperpurified Delivery System) contact lenses. These gas-permeable rigid lenses do not contain water like soft contacts, are resistant to deposits and less likely than soft contact lenses to harbor bacteria. Since they are rigid, they are also easier to handle, retain their shape, and provide crisper vision. The U.S. Food and Drug Administration approved these lenses for continuous wear of up to seven days.
While the HDS® lenses improve vision as they are worn, the next step in the technology was to use these materials to construct 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.
Leveraging what it learned from NASA’s experiments, Paragon Vision Sciences developed Corneal Refractive Therapy. 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 is clearer, natural vision lasting all day, possibly eliminating the need for daytime contacts or glasses.
This technology now provides 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. More than 93 percent achieved 20/32 vision or better — exceeding driving requirements in most states.2
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 amazing research, check out the following articles:
The Children’s Overnight Orthokeratology, Investigation (COOKI) Pilot Study JEFFREY J. WALLINE, OD, PhD, FAAO, MARJORIE J. RAH, OD, PhD, FAAO, and LISA A. JONES, PhD, FAAO. OPTOMETRY AND VISION SCIENCE, 2004
Paragon CRT® Contact Lenses Clinical Study, April 2002