Ten-Year Structural Stability After Pediatric Athens Protocol Cxl For Keratoconus: Topography-Guided Minimal Apex Ablation Combined With High-Fluence Cross-Linking And Long-Term Corneal Remodeling And Visual Rehabilitation

To report 10-year tomographic and visual outcomes of pediatric progressive keratoconus treated with combined topography-guided corneal normalization and high-fluence corneal cross-linking (Athens Protocol). The protocol prioritizes structural symmetry and minimal apex tissue removal rather than refractive targeting. This case highlights long-term biomechanical stability and progressive corneal remodeling, underscoring the synergistic flattening effect of combined surface ablation and cross-linking and its refractive implications. A unique aspect is the very long, detailed follow-up with near-annual imaging, capturing pediatric evolution despite the practical challenge of limiting eye rubbing in this age group.

A 14-year-old boy presented with bilateral advanced progressive keratoconus, CDVA worse than 20/40, habitual eye rubbing, and significant hyperopic astigmatism. Thinnest corneal data by tomography and OCT under 450um in both eyes. Given speed of progression and visual morbidity, intervention ensued with parental consent.

Bilateral Athens Protocol CXL was applied. Topography-guided surface ablation was designed exclusively for corneal normalization, prioritizing minimal tissue removal— at the cone apex, the thinnest and biomechanically most vulnerable. Optical zone was 5.0 mm / 2 mm transition zone. Treated cylinder amount and axis derived from topographic data rather than subjective refraction. Cross-linking followed using 6 mW/cm² for 15 minutes.

Recovery was uneventful. As early as 2 weeks cone regularization and stability were documented with visual function competence from first month and on.

At 10 years (age 24), binocular uncorrected visual acuity exceeded 20/20. Tomography demonstrated sustained stabilization with additional mild corneal flattening compared to baseline and 3-year imaging. No ectatic progression, posterior elevation increase, or progressive thinning occurred. The progressive flattening observed reflects the synergistic biomechanical effect of combined normalization and cross-linking rather than isolated refractive change. 

Serial long-term maps demonstrate durable symmetry and stability despite the background pediatric risk profile (allergy/eye rubbing).

This 10-year follow-up confirms durable biomechanical stabilization and progressive structural remodeling after pediatric Athens Protocol CXL. The synergistic flattening effect of combined topography-guided normalization and cross-linking may continue over years and is not fully predictable in magnitude. Therefore, refractive emmetropia should not be a surgical target in this setting. Structural symmetry and apex preservation remain the primary objectives. Long-term potential added flattening must be anticipated as refractive evolution in these patients. Near-annual tomography over a decade supports that this strategy can provide lasting stability and excellent functional vision in a high-risk pediatric keratoconus phenotype.