Standard Corneal Crosslinking Long-Term Outcomes Superior to Accelerated Crosslinking

Standard corneal crosslinking (CXL) can deliver superior improvements in visual acuity and keratometry compared with accelerated crosslinking, according to research published in Eye. The study shows that both accelerated and standard corneal crosslinking can safely and effectively stabilize keratoconus at 5 years.

Researchers sought to compare the long-term effectiveness of standard (UV intensity: 3 mW/cm²; duration: 30 minutes) and accelerated corneal crosslinking (UV intensity: 9 mW/cm²; duration: 10 minutes) in the treatment of keratoconus.

The researchers followed 176 eyes of 141 patients for 5 years post-CXL to evaluate primary outcome measures of visual acuity, maximum keratometry (Kmax), and central steepest keratometry (K2). Both surgical protocols improved visual acuity compared with baseline (P <.05), although the improvement for mean habitual visual acuity (10.2 vs 4.9 logMAR letters; P =.013) and mean pinhole visual acuity (5.7 vs 0.2 logMAR letters; P <.001) were significantly greater for standard corneal crosslinking compared with accelerated corneal crosslinking.

Standard corneal crosslinking also significantly decreased Kmax and K2 compared with baseline (P <.05), which may be related to greater improvements in visual acuity for this group. 

The authors suggest, “A greater improvement in visual acuity with standard CXL than with accelerated CXL may be associated with greater improvement in keratometry in the former group as the decreased vision in keratoconus is due to the changes in the corneal shape.” 

Accelerated CXL produced significant thinning at 5 years post-CXL, but this difference was not clinically meaningful. Safety outcomes were similar for both groups with adverse events reported for 17% of eyes in the standard CXL group and 22.4% of eyes in the accelerated CXL group (P =.483). Haze was the most commonly reported adverse event that affected 76.5% of eyes in the standard CXL group and 94.1% of eyes in the accelerated CXL group.

These results may be influenced by differences in disease severity and postoperative management between the 2 groups.