Keratoconus and other forms of corneal ectasia have been difficult diseases to treat. The disease can be progressive with complete distortion and failure of the cornea, or can cease progression at some point. There is no way to know when progression will stop, but keratoconus usually begins in the teenage years or twenties, and rates of progression vary. Pellucid marginal degeneration is a variant that begins later in life usually in the fifties to seventies. Refractive surgery induced corneal ectasia occurs when too much tissue has been removed from the bed causing loss of corneal structural integrity. In all of these forms the cornea bows outwards as positive pressure from fluid in the eye pushes the weakened cornea outwards creating the cone shape. The more the progression, the thinner the cornea becomes as it stretches. The unfortunate part of treating this problem is that the further the progression, the more tissue is required for reconstructive laser treatment, yet less is available. Therefore, the earlier treatment can be performed the easier the procedure and the better the visual outcome.
The treatment of Keratoconus and other forms of corneal ectasia (corneal weakening causing bowing forward of the cornea) have traditionally been treated with different types of rigid contact and scleral lenses to help the vision, and if the ectasia continued to progress, with corneal transplant. No form of lens prevents progression of this disease, and as the disease progresses, fitting specialized lenses such as scleral lenses becomes more difficult and wearing them more uncomfortable.
Corneal transplant itself creates significant new problems as a donor cornea from a cadaver must be used, which is not necessarily a matching shape to the recipient. The cornea is then sewn in to the recipient, and virtually all will have some level of irregular astigmatism limiting vison and visual quality. Furthermore, the biggest problem is that 40% of corneal transplants fail within 10 years, requiring either another transplant, or a partial cornea transplant. Cornea transplants are not a permanent solution.
The path towards a permanent solution started in 1999 with the Dresden Protocol created by Theo Siler, MD, one of the most brilliant minds in the refractive surgery world. This saturated the cornea with riboflavin and then applied a specifically measured amount of ultraviolet light to catalyze a reaction to increase the number of bonds between corneal cells increasing strength and rigidity. This procedure, termed Corneal Cross Linking, stops the progression of corneal ectasia, but only mildly flattens the steep cone shaped cornea and does not significantly improve vision or visual quality.
Dr. Siler also invented topographic guided ablation on the WaveLight laser (market name Contoura), which utilizes topographic images to create a laser pattern to reduce irregularity. This led to the next step was taken by A. John Kanellopoulos, another brilliant mind in the field of ophthalmology, who combined corneal cross linking with topographic guided ablation and called it the Athens Protocol. Topographic guided ablation would reduce the irregularity of the cornea, creating a more “normal” shape, and the corneal cross linking would help to strengthen the cornea after this was done. This normalization is used to create a less irregular corneal surface, allowing for the possibility of better optics and visual quality, improvement of vision, easier fitting of lenses as necessary, and of course cross linking to stop progression. This revolutionized the treatment of corneal ectasia, and now this treatment became the gold standard in the rest of the world for the treatment of keratoconus and other forms of corneal ectasia.
The next steps were taken by Manoj Motwani, MD, who in 2017 published the San Diego Protocol and LYRA Protocol (Layer Yolked Reduction of Astigmatism. These utilized new thinking and new scientific understanding to understand the relationship between the distortion created by higher order aberrations/corneal irregularity and lower order astigmatism (the cornea out of round).and demonstrated the extremely low incidence of actual posterior corneal astigmatism. This procedure created a more uniform cornea, and now instead of just reducing irregularity, the goal was to also improve vision quantity and visual quality as much as possible. The United States Patent Office granted a patent to Dr. Motwani for this procedure (European Patents Pending).
The final major step was taken by Manoj Motwani, MD in 2020 with the CREATE+CXL Protocol (Corneal Repair Epithelium and Topography Enhanced + Corneal Cross Linking) where he also began to treat the part of the corneal irregularity hidden by epithelial compensation. This part of the irregularity is not measurable by topographic guided systems, but is measurable separately by epithelial mapping systems. This turned out to be highly significant, as Dr. Motwani discovered a large part of the corneal irregularity was not being treated by the topographic guided systems. Dr. Motwani has been granted a second patent on the treatment of this “hidden” irregularity to create a more uniform, normal cornea (European Patents Pending)
The CREATE+CXL Protocol has led to a significant decrease in corneal irregularity and increase in the quantity and quality of vision in comparison to the Athens and San Diego Protocols, with some patients having corneas that appear almost “normal” on topography from the decreased corneal irregularity.
It is important to understand that the primary goal of this procedure is to PREVENT corneal transplant, and the secondary goal is to normalize the cornea in a way that soft contact lenses can be used, or in some cases even allow for vision without glasses or contacts. The CREATE+CXL Protocol was designed to maximize the amount of vision and the number of eyes that can see without glasses or contacts, as well as to provide the best possible visual quality. How much the eye(s) can be corrected depends on the amount of corneal tissue present, since the cornea gets thinner as the ectasia progresses.
Topographic guided ablation and corneal cross linking are performed consecutively, on the same day one after the other. Since it is necessary to remove the surface epithelium to perform both, initial healing time is similar to a PRK, with the epithelium taking from 3-7 days to heal. As the cross linking is now “epi-off” it is significantly deeper and stronger than the more common “epi-on” cross-linking.
Many patients note improved vision and return to work within 1-2 weeks, and improvements to vision continue to occur over 6-12 months due to the dynamic nature of epithelial healing and cross-linking.
We fundamentally believe that this is now the best keratoconus treatment available, and has the major advantage of being a permanent solution that allows you to keep the patient’s natural cornea, and has the potential to make the most “normal” cornea of any keratoconus treatment allowing patients the freedom to lead a virtually normal life.
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