Wave Front–Guided Photorefractive Keratectomy Using a High-Resolution Aberrometer After Corneal Collagen Cross-Linking in Keratoconus

Abstract

Sequential WFG PRK using the iDesign system and the STAR S4 IR excimer laser after CXL is an effective option to correct the spherocylindrical error and to minimize the level of higher order aberrations in mild and moderate keratoconus if the maximum intended ablation depth does not exceed 15% of the minimal corneal thickness.

Simultaneous versus Sequential Accelerated Corneal Collagen Cross-Linking and Wave Front Guided PRK for Treatment of Keratoconus: Objective and Subjective Evaluation

“…The MRSE was reduced from a mean preoperative value of −3.7 ± 2.4 and −3.8 ± 2.6 in simultaneous and sequential groups, respectively, to a mean postoperative value of −1.3 ± 0.79 and −1.00 ± 0.68 at the last follow-up visit. Similar results were recorded by Shaheen et al using sequential WFG PRK at least one year after CXL in keratoconus [18]. Kymionis et al [4] and Alessio et al [21] reported in eyes with keratoconus receiving simultaneous t-PRK + CXL a reduction of the MRSE of 1.74 D and 1.75 D, respectively.…”

“…However, safety and efficacy of simultaneous versus sequential PRK after CXL are still debatable as CXL alone may or may not improve the refractive status of the eye; thus it is logical to wait till refractive stability following CXL procedure [18]. In another point of view, performing both procedures at the same time appeared to minimize the potential superficial stromal scarring and corneal haze resulting from PRK.…”

Reduced High-order Aberrations using Wavefront-guided Partial Photorefractive Keratectomy and Accelerated Epithelium-off Corneal Cross-linking for Keratoconus

“…These results are similar to the results achieved by Shaheen et al 23 in their case series of waveguided PRK and CXL, which demonstrated a significant reduction in total, coma, and trefoil, and an improvement in spherical aberration. Shaheen et al, 23 however, differed in their approach in that the waveguided PRK was applied to keratoconic eyes that had previously undergone CXL rather than performing the procedures simultaneously.…”

“…Shaheen et al, 23 however, differed in their approach in that the waveguided PRK was applied to keratoconic eyes that had previously undergone CXL rather than performing the procedures simultaneously. It is reassuring to see similarly significant improvements in HOAs in both delayed and simultaneous approaches.…”

Two-year follow-up of corneal cross-linking and refractive surface ablation in patients with asymmetric corneal topography

“…Shaheen studied Wavefront Guided PRK and cross-linking only for keratoconus 17. The study showed no corneal complications and found that high order aberrations decreased compared with preoperative values (especially coma and trefoil) in the first month and further decreased over time.…”