Keratoconus and other forms of corneal ectasia have been complex diseases to treat. The condition can be progressive with complete distortion and failure of the cornea or cease progression at some point. There is no way to know when progression will stop, as it usually starts in the teenage years or twenties. Pellucid marginal degeneration starts later in life, usually in the fifties to the 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 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 patients are treated, the better the visual outcome.
The treatment of Keratoconus and other forms of corneal ectasia (corneal weakening causing bowing forward of the cornea) has traditionally been treated with different types of rigid contact and scleral lenses to help the vision, and if the ectasia continues to progress, with a corneal transplant. No form of lens prevents the progression of this disease, and as the disease progresses, fitting specialized lenses such as scleral lenses becomes more difficult and wearing them more uncomfortable.
The corneal transplant creates significant new problems as a donor cornea from a cadaver must be used. A donor cornea may not be a matching shape to the recipient. The cornea is sewn into the recipient, and virtually all will have astigmatism limiting vision and visual quality. The biggest problem is that 40% of corneal transplants fail within ten years, requiring either another or partial cornea transplant. Cornea transplants are not permanent solutions.
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. His protocol saturates the cornea with riboflavin and then applies a precisely measured amount of ultraviolet light to catalyze a reaction. The reaction increases the number of bonds between corneal cells, increasing their 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 taken by A. John Kanellopoulos, another brilliant mind in the field of ophthalmology. He 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. This normalization creates a less irregular corneal surface, allowing for better optics and visual quality, improved vision, easier fitting of lenses as necessary, and cross-linking to stop the progression. The Athens Protocol revolutionized the treatment of corneal ectasia and has become the gold standard in the rest of the world for treating keratoconus and other forms of corneal ectasia.
Manoj Motwani, MD, took the following steps in 2017 by publishing the San Diego Protocol and LYRA Protocol (Layer Yolked Reduction of Astigmatism). These utilized new thinking and scientific understanding to comprehend the relationship between the distortion created by higher-order aberrations/corneal irregularity and lower-order astigmatism (the cornea out of round). They demonstrated an 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 also to improve vision quantity and visual quality significantly. The United States Patent Office granted a patent to Dr. Motwani for this procedure (European Patents Pending).
Manoj Motwani, MD, took the final major step 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 finding 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 an increase in the quantity and quality of vision compared 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 essential to understand that the primary goal of this procedure is to PREVENT corneal transplant, and the secondary goal is to normalize the cornea so that patients can use soft contact lenses 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 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, the initial healing time is similar to a PRK, with the epithelium taking 3-7 days to heal. As the cross-linking is now “epi-off,” it is significantly deeper and more robust than the more common “epi-on” cross-linking.
Many patients note improved vision and return to work within 1-2 weeks. Improvements to vision continue to occur over 6-12 months due to the dynamic nature of epithelial healing and cross-linking.
The CREATE+CXL Protocol is now the best keratoconus treatment available. It’s a permanent solution that saves 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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