• Written By:
    Cornea/External Disease, Refractive Mgmt/Intervention

    This retrospective study assessed whether the introduction of corneal collagen crosslinking (CXL) in Canada affected the number of corneal transplants performed for keratoconus.

    Study design

    The authors reviewed 31,943 corneal transplant procedures performed in Ontario and British Columbia over an 18-year period (1998–2016). Corneal collagen crosslinking was introduced in 2008. Researchers used data collected from records at the Eye Bank of Canada—Ontario/British Columbia Divisions.


    There was no change in the absolute number of transplants performed for keratoconus during the study period. Although there was a significant decrease in the proportion of total transplants for keratoconus after 2008 (P<0.001), the total number of grafts and endothelial keratoplasties increased (both P<0.001). There were no changes in the number of penetrating keratoplasty/deep anterior lamellar keratoplasty (DALK) procedures performed for indications other than keratoconus.


    The study period only included 8 years after availability of CXL. This may not be a long enough follow-up to detect a significant change in progression to the level of requiring keratoplasty.

    Clinical significance

    The total number of transplants performed for keratoconus did not change significantly in the 11 years prior to availability of CXL relative to the 8 years after adoption of CXL. The percentage of transplants for keratoconus decreased, but this was due to a significant increase in the total number of transplants, fed by the significant increase in endothelial keratoplasty procedures.