Article

IS THIS THE NEW NORM?

CORNEAL CROSS-LINKING FOR KERATOCONUS

It seems as though more and more patients are being diagnosed with keratoconus today. Corneal topography and advanced corneal thickness and shape measurements can help practitioners detect keratoconus much earlier. With more keratoconus patients in our offices than ever, is corneal cross-linking (CXL) the new normal for early keratoconus? What effect would this have?

As of 2014, 10% to 20% of keratoconus patients are still undergoing corneal transplants (Davidson et al, 2014). Is it possible to do CXL in a broad approach to alter this number? How long would it take before a noticeable shift in transplant surgery would occur?

We can look to our Dutch friends for these very answers. The Dutch started performing CXL in 2007, and it is now well established as a treatment for keratoconus. One study evaluated the number of corneal transplants performed from 2005 to 2007, which was before CXL was available, and compared that to the number of transplants performed during the years from 2012 to 2014. They noted that 269 transplants were performed during the three-year pre-CXL period, whereas 201 were performed in the years after CXL was available. Age, gender, and visual acuity were similar between the two groups (Godefrooij et al, 2016).

These data reveal a 25% reduction in the number of corneal transplants in the years following the introduction of CXL. If the trend continues, 25% may eventually become 50% and even higher.

Early Diagnosis Is Key

A key to the future success of CXL is continued earlier diagnosis and a better standardization of when it is ideal to perform the procedure. If we wait until the keratoconus has advanced, these patients may require specialty lenses for the rest of their lives. However, if we can come to a diagnosis before the refractive error becomes substantial, these patients may be able to maintain clear vision with glasses or non-custom contact lenses.

In our practice, we are on the hunt for early keratoconus patients. We look for any patient who has advancing astigmatism. We also think that it is critical to evaluate a screening topography on all patients. Advanced autorefractor/keratometer instruments on the market measure aberrations and topography within their standard examination. We use these instruments in our offices as advanced screening tools.

Additionally, we talk with all of our keratoconus patients about CXL, whether their condition is advancing or not. For most patients who are not advancing, we let them know that it is available but that they may not need it. For any patients who are advancing, we earnestly encourage the procedure.

The Verdict

We believe that CXL is the new standard for keratoconus patients. If a patient has advanced or is suspected to advance, join the new normal and get that patient cross-linked. CLS

For references, please visit www.clspectrum.com/references and click on document #277.