Five-year corneal cross-linking outcomes: A Save Sight Keratoconus Registry Study

Area of Science:

• Ophthalmology
• Corneal Surgery
• Vision Science

Background:

• Keratoconus is a progressive corneal ectasia leading to vision impairment.
• Epithelium-off cross-linking (CXL) is a treatment option for keratoconus.
• Long-term outcomes of CXL require further investigation.

Purpose of the Study:

• To evaluate the long-term efficacy and safety of epithelium-off cross-linking (CXL) in patients with keratoconus.
• To assess changes in visual acuity, maximal keratometry (Kmax), keratoconus 2 (K2), and thinnest corneal thickness (TCT) over 5 years.
• To identify the proportion of patients who respond poorly to CXL.

Main Methods:

• An observational registry study involving 41 centers across 5 countries.
• Inclusion of 976 eyes from 794 patients with follow-up data up to 5 years.
• Primary outcomes: mean changes in visual acuity (VA), Kmax, K2, and TCT; Secondary outcomes: percentage of eyes with worsening, stable, or improving outcomes.

Main Results:

• Significant improvement in mean VA at 1 and 5 years (p < 0.001).
• Mean Kmax decreased by 1.2 D in year 1 (p < 0.01), with sustained flattening.
• A small proportion of eyes (4.1-7.5%) showed poor response in VA or keratometry at 5 years.

Conclusions:

• Epithelium-off CXL is effective in stabilizing keratoconus in the majority of patients up to 5 years.
• Most patients experience stable or improved visual acuity and corneal topography.
• A minority of patients may not achieve stabilization and could experience reduced vision.