This retrospective study compared the outcomes of patients who underwent either standard Dresden or accelerated corneal collagen cross-linking (CXL) for keratoconus.

Study design

Each participant received at least 2 clinical exams, 1 year apart, both before and after surgery. Patients were included in the study if they showed preoperative progression that was re-examined after surgery. Twenty-nine patients underwent each procedure. Scheimpflug imaging was used to measure D values (ie, a combination of keratoconus topographic parameters), thinnest pachymetry, and Kmax values.

Outcomes

Keratoconus progressed before surgery in both groups, with a significant reduction in corneal thickness and an increase in D value. This progression was successfully halted in both groups after surgery. There were no significant differences in D values between the groups before surgery; however, the Dresden group showed a significant decrease in D value after surgery, which was not seen in the accelerated group (Dresden: −0.47, P<0.01; accelerated: 0.04, P=0.77).

Limitations

This was a relatively small retrospective study. The follow-up visits were not standardized to specific time points for all patients.

Clinical significance

This study analyzed data from eyes with documented keratoconus progression and found that the standard Dresden protocol and accelerated CXL both halted progression of keratoconus. However, only the standard protocol was associated with improved outcomes over baseline.