Factors predicting successful customized excimer laser treatment in irregular corneas.

PURPOSE: To identify factors associated with a successful wavefront-guided customized treatment (WG-CT) with an excimer laser in highly aberrated corneas.

SETTING

VISSUM Alicante Spain.

DESIGN

Retrospective consecutive noncomparative case series.

METHODS

Treatment was performed with the WG-CT Amaris excimer laser using the ORK-CAM software for the calculation of the ablation profile. Eyes of patients with significantly aberrated corneas, including postrefractive and keratoplasty procedures or high irregular astigmatism with significant higher-order aberrations (HOAs) that had WG-CT were included. Refractive outcomes, HOAs, and visual outcomes were recorded. Statistical analysis was performed to identify factors associated with technical (based on HOAs) or refractive outcome success.

RESULTS

The study included 55 treatments of 51 eyes (35 patients). The postoperative uncorrected distance visual acuity was 0.2 logarithm of the minimum angle of resolution or better in 72% of the eyes, and the postoperative residual manifest refraction spherical equivalent was ±0.50 diopter in 56% of the eyes, whereas 11% of the eyes lost 1 line or more in corrected distance visual acuity. Successful reduction in the total root mean square (RMS) of HOAs occurred in 36 eyes (65%), and these eyes had a significantly higher preoperative RMS of HOAs (1.45 ± 0.93 μ vs 0.91 ± 0.34 μ, P = .003) and preoperative coma-like aberrations (1.09 ± 0.83 μ vs 0.55 ± 0.28 μ, P = .001). In multivariate analysis, posthyperopic treatment eyes were less likely to achieve refractive outcome success (odds ratio = 0.09, P = .02).

CONCLUSIONS

WG-CT in highly aberrated corneas had a limited refractive predictability. Eyes with preoperative coma-like aberrations are more likely to benefit from a reduction in HOAs. Posthyperopic treatment is associated with a higher rate of refractive surprises.