Keratoplasty for keratoconus on the decline

This retrospective review shows that the introduction of corneal collagen crosslinking (CXL) may have reduced the number of keratoplasty procedures for keratoconus. Investigators compared the number of keratoplasty procedures performed before and after the procedure became well established in their eye clinic at Oslo University Hospital in Norway.

This is the first study to report a significant decrease in the keratoplasty rate following the introduction of CXL, which the authors attribute to timing. Previous studies examined keratoplasty rates immediately after the new technique was introduced, instead of waiting, as they did, until the procedure became well-established.

The authors compared the keratoplasty rate in patients with keratoconus from 2005 to 2006, the year before CXL was introduced in their clinic, to the surgery rate in 2013 to 2014. Even though they performed almost twice the number of keratoplasties from 2013 to 2014, the frequency for keratoconus was almost halved (55 vs. 26 eyes, P=0.003). Additionally, a larger number of patients undergoing keratoplasty in 2013-2014 had stage 4 keratoconus (63.6% vs. 96.2%, P=0.001). Two patients who had CXL and later underwent keratoplasty did so due to persistent difficulty with contact lens fitting after CXL, not due to keratoconus progression.

Unfortunately, every patient with keratoconus who had surgery in 2013-2014 was not referred until they had advanced disease and were ineligible for CXL. The authors urge physicians to carefully screen patients for keratoconus – particularly those with a family history and those with conditions such as Down syndrome and noninflammatory connective tissue diseases – for timely referral for CXL treatment.  

While larger, longitudinal studies are required to confirm their finding, the authors write that there is reason to believe that the reduction noted in this study is in great part a result of the introduction of CXL.