Cross-linking in Progressive Keratoconus Using an Epithelial Debridement or Intrastromal Pocket Technique After Previous Corneal Ring Segment Implantation

PURPOSE: To evaluate and compare the clinical and confocal microscopic outcomes achieved with two different procedures for cross-linking (CXL) in eyes with keratoconus: CXL with epithelial debridement and CXL with intrastromal pocket. METHODS: This retrospective study included 27 eyes of 21 patients (age range: 18 to 53 years) diagnosed with keratoconus who underwent implantation of intracorneal ring segments and CXL with two different techniques: CXL with previous epithelial debridement (classic group, 16 eyes) and CXL with intrastromal pocket for riboflavin infusion (pocket group, 11 eyes). Visual, refractive, topographic, aberrometric, and pachymetric data were evaluated during 12-month follow-up. RESULTS: No statistically significant differences between the classic and pocket groups were found in postoperative visual acuity ( P ≥.71), refraction ( P ≥.15), keratometry ( P ≥.28), corneal aberrations ( P ≥.13), or central pachymetry ( P ≥.21). A statistically significant improvement in uncorrected visual acuity found at 3 months postoperatively in both groups ( P <.03) was consistent with a change in manifest sphere. Mean keratometric reduction at 12 months was 0.03 diopters (D) in the classic group ( P =.55) and 0.40 D in the pocket group ( P =.05). No significant changes in corneal higher order aberrations or central corneal thickness were found in either group ( P ≥.14). CONCLUSIONS: Cross-linking surgery with creation of an intrastromal pocket seems to provide similar clinical outcomes compared to the classic CXL technique.