Prospective, randomized, double-blind, contralateral eye comparison of myopic LASIK with optimized aspheric or prolate ablations
Chayet A, Bains HS.
To compare the postoperative outcomes of aspheric or prolate LASIK for myopia and myopic astigmatism.
In this double-blind, bilateral, randomized trial, 40 patients (80 eyes) with -0.75 to -7.00 diopters (D) of manifest refraction spherical equivalent (MRSE) underwent optimized aspheric treatment zone ablation (OATz group) in 1 eye and optimized prolate ablation (OPA group) in the fellow eye. Six-month postoperative outcomes were compared for MRSE and visual acuity, contrast sensitivity, patient satisfaction, ocular higher order aberrations (HOAs), and spherical aberration. The Wilcoxon signed rank test, Mann-Whitney U test, and paired t test were used for testing differences between groups. P<.05 was statistically significant. Main outcome measures included HOAs, spherical aberration, visual and refractive outcomes, and contrast sensitivity.
Postoperatively, 36 patients (72 eyes) were evaluated. The MRSE was -0.07±0.23 D for the OPA group and +0.02±0.24 D for the OATz group (P>.05). Two (5%) eyes in the OPA group and 1 (3%) eye in the OATz group (P=.114) lost 1 line of corrected distance visual acuity. Postoperative visual acuity was not statistically different between groups (P>.05). Statistically lower change was noted in spherical aberration (0.011 μm) in the OPA group versus the OATz group (0.099 μm) (P<.001). Statistically higher induction of coma was noted in the OPA group (P=.035). No statistically significant differences were noted in photopic, mesopic, or glare contrast sensitivity and patient satisfaction between groups (P>.05, for all comparisons).
The refractive and visual outcomes of OPA and OATz were equivalent. However, the postoperative optical quality of OPA-treated eyes was better