Comparison Between the Wavefront-Optimized and Custom-Q Aspheric Ablation Profiles in Myopic Eyes With Two Different Q-targets: A Contralateral Eye Study.

Abstract

To compare two aspheric ablation profiles in myopic refractive surgery using different asphericity targets. Patients underwent laser in situ keratomileusis (LASIK) with the WaveLight EX500 laser platform (Alcon, WaveLight Laser Technologie). Asymmetric surgery was performed, programming the wavefront-optimized (WFO) ablation profile in one eye and the custom-Q (CQ) profile in the contralateral eye. The patients were divided into two groups following a systematic randomization method. The Q-target programmed for the preoperative Q group was equal to the preoperative asphericity of the CQ profile, and for the -0.6 Q-target group, the Q-target was set to -0.6. The study included 100 patients (200 eyes). Both groups had comparable safety and efficacy indexes greater than 1. A similar oblate shift in postoperative asphericity was seen in both groups regardless of the ablation profile and programmed Q-target. Asphericity was 0.33 ± 0.34 and 0.35 ± 0.29 (P = .18) in the preoperative Q group and 0.26 ± 0.28 and 0.26 ± 0.27 (P = .89) in the -0.6 Q-target group for WFO and CQ, respectively. A lower spherical aberration was found with CQ compared to WFO when the Q-target was set to -0.6: 0.211 ± 0.121 versus 0.144 ± 0.114 (P < .01). However, no statistically significant differences were found when the preoperative Q-target was used. WFO and CQ treatments are similar in terms of refractive and visual outcomes. CQ offers greater control over the increase in positive spherical aberration after myopic refractive surgery, but it does not represent an advantage over WFO in the oblate shift in postoperative asphericity regardless of the Q-target programmed. [J Refract Surg. 2022;38(11):698-707.].