Traditionally, patients with advanced keratoconus had very few options for treating corneal ectasia. In the early days, the only option they were offered was generally a full corneal transplant (penetrating keratoplasty). More recently, partial thickness corneal transplants (anterior lamellar keratoplasty (ALK, DALK)) came into play as a slightly less invasive procedure. Intrastromal corneal ring segments, such as Intacs, are another option that were under a human device exemption by the FDA in 2004. These synthetic rings are inserted in the cornea to improve the curvature of the cornea. And while each of these techniques may still offer excellent results for patients today, both the transplants and the synthetic inlays carry the risk of being rejected by the body. Corneal allogenic intrastromal ring segments (CAIRS) came into existence as an alternative to Intacs’ synthetic inlays. CAIRS imitate synthetic segments, like Intacs, but are made out of corneal tissue for improved biocompatibility.
As you can see, ophthalmologists and researchers have been hard at work over the last few decades seeking to push the boundaries of vision restoration for keratoconus patients. This was the motivation behind the invention of CTAK, which took place right here at CLEI.
Advanced Keratoconus Treatment with Improved Techniques
CTAK was born because our doctors wanted to improve upon existing techniques and find a new way to treat advanced cases of keratoconus – one that could offer improved corneal topography and visual acuity, with fewer risks than the existing treatments.
The CTAK procedure was the answer. It uses inlays made from gamma-irradiated donated tissue to reshape the cornea and improve a patient’s vision. Because the inlays are sterilized via gamma irradiation and no longer contain any donor cells, the risk of rejection when compared with a corneal transplant is much lower. And unlike corneal transplants, CTAK is fully reversible. So, in the unlikely event that a patient’s vision worsens or the inlay is rejected, it can simply be removed and even replaced.
CTAK also improves upon the technique used with Intacs or CAIRS. How so? With Intacs or CAIRS, inlays are available in a few different sizes, but they are not custom cut. They are pre-produced with fixed dimensions. In CTAK, on the other hand, a femtosecond laser custom cuts both the tissue addition and the channel where it will be placed in the cornea. This fully customized process allows for visual acuity and corneal topography to be improved even further.
CTAK Clinical Trial Results
Clinical trials for CTAK began at CLEI in 2016 and the results were outstanding.
Below are the average results the patients in the trial experienced:
- uncorrected vision (without glasses) improved by about 5 logMAR lines (from 1.21 logMAR lines (20/327) to 0.61 logMAR lines (20/82)).
- vision in glasses improved by over 3 logMAR lines (from 0.62 logMAR lines (20/82) to 0.34 logMAR lines (20/43))
- and glasses prescriptions improved (from -6.25 diopters to -1.61 diopters).
As for corneal topography, the topographic analysis in the same clinical trial showed a significant flattening of the cornea, with an average decrease of -8.4 D in Kmean and -6.9D in Kmax at 6 months after the procedure.
Expanding the Keratoconus Treatment Toolbox
As with all surgical procedures, not everyone will be a candidate for CTAK. Still, countless patients can benefit (and already have benefitted) greatly from this breakthrough procedure. It has proven highly effective – even for some patients who believed a corneal transplant was their only option. Our doctors are proud to have contributed a valuable new tool to the medical community for treating this serious condition.
While there is currently no cure for keratoconus, there are effective ways to manage it. At CLEI, we recommend a three part treatment plan, which we call KC 1, 2, 3. First, we must halt the progression of the keratoconus. Second, we can improve the keratoconus topography, which is where CTAK may come in. And third, we can take further steps to improve keratoconus vision. Each step in keratoconus treatment is vitally important, and because each case of keratoconus is unique, no two treatment plans are ever the same.
CLEI’s Focus on Innovative Research Continues
With decades of experience treating keratoconus patients at the CLEI Center for Keratoconus, our dedication to pushing treatment options forward is unwavering. We continue to innovate, research, and perform clinical trials for groundbreaking treatments.
If you or a loved one has been diagnosed with keratoconus, we encourage you to schedule an appointment with our team of experts today. We would be delighted to help craft a personalized treatment plan to help you manage your keratoconus.
We can also discuss the options available to improve your corneal topography, which may include CTAK, topography-guided PRK, Intacs, or in the case of severe corneal scarring, a corneal transplant. Our team of doctors has expertise in all of these procedures and more, so you can rest assured that they can guide you towards the treatment options that will offer you the best possible outcomes and, most importantly, an improved quality of life.
