Control of Induced Spherical Aberration in Moderate Hyperopic LASIK by Customizing Corneal Asphericity

PURPOSE: To compare differences in induced aberrations and visual acuity after wavefront-optimized LASIK and aspheric- customized LASIK for the treatment of hyperopia. METHODS: Forty consecutive eyes underwent uneventful LASIK for treatment of moderate hyperopia (+ 3.82 +/- 0.63 diopters [ D] [+ 2.75; + 5.125]). A standard procedure was performed in the wavefront- optimized LASIK group ( n = 24), whereas a postoperative Q- factor equal to zero was scheduled in the aspheric- customized LASIK group ( n = 16). RESULTS: At 6 months, mean spherical aberration for a 6- mm pupil diameter was - 0.39 +/- 0.23 mu m ( range: - 0.76 to 0.01 mu m) and Q- factor was - 0.52 +/- 0.22 ( range: - 1.00 to - 0.12 mu m) in the wavefront- optimized group and 0.04 +/- 0.18 mu m ( range: - 0.34 to 0.29 mu m) and - 0.04 +/- 0.25 ( range: - 0.64 to 0.40 mu m) in the aspheric- customized LASIK group ( P =.05). All remaining outcomes showed no significant differences between groups. UDVA was 20/ 18.69 +/- 0.15 ( range: 0.80 to 1.20) in the wavefront- optimized LASIK group and 20/ 20 +/- 0.17 ( range: 0.50 to 1.20) in the aspheric- customized LASIK group. One patient in the wavefront- optimized LASIK group lost two or more lines of CDVA and no lines were lost in the aspheric- customized LASIK group. CONCLUSIONS: The results in this small cases series suggest that using an aspheric- customized ablation profile with a target Q- factor equal to 0 in moderate hyperopic LASIK is statistically compatible with a diminishing induced spherical aberration without altering procedural safety when the WaveLight Allegretto 400- Hz excimer laser platform ( Alcon Laboratories, Inc., Fort Worth, TX) is used.