Symmetrical Versus Asymmetrical PresbyLASIK: Results After 18 Months and Patient Satisfaction

The aim of this study was to report visual, topographic, and satisfaction comparative results between symmetrical and asymmetrical presbyLASIK after 18 months.

Longitudinal, comparative case series of hyperopic presbyopes who underwent presbyLASIK, in a private clinical setting. Monovision symmetrical (plano target both eyes) versus asymmetrical [dominant eye (DE) = plano target; nondominant eye (NDE) = -0.50 diopter (D) target]. Pre- and postoperative variables included monocular and binocular, distance and near, uncorrected visual acuity (VA), best corrected visual acuity, spherical equivalent, addition (Add), topography SimK (Km), and topographic astigmatism. Topographic central corneal power increase was measured 3 and 18 months postoperatively. Data were reported as mean, range, and standard deviation and analyzed with Student t-test (P < 0.05 for statistical significance) and Pearson correlation coefficients.

The symmetrical group consisted of 16 patients and the asymmetrical group of 14 patients, with a mean age of 53.5 ± 2.3 and 51.9 ± 2.5 years. Postoperative results, after 18 months, for symmetrical versus asymmetrical presbyLASIK were as follows: distance UCVA 0.8 ±0.20; 0.9 ± 0.2 (P < 0.01); near UCVA 0.9 ± 0.2; 0.8 ± 0.2 (P < 0.01); SE -0.20 ± 0.50; -0.3 ± 0.3D (P < 0.01); Add 0.5 ± 0.5; 0.9 ± 0.9 (P < 0.01); mean Km 44.8 ± 1 D; 43.9 ± 1.1 D (P < 0.01); mean central corneal power differential 1.4 ± 0.8 D; 1.7 ± 1.1 D (P < 0.01), respectively. Stability: -0.16 D, DE -0.13 D and NDE -0.16 D, and SE predictability -0.40; DE -0.28 D and NDE -0.53 D. Safety index 1.0; 1.0, efficacy distance VA 0.8; 0.9, and near VA 0.90; 0.8. More than 90% were within ±0.50 D of the intended target. Twenty eyes required enhancement, and results were not significantly different. Mean satisfaction (0-10 points) for symmetrical patients was 7.0 ± 2.6 and 7.3 ± 2.8 points for asymmetrical patients.

Symmetrical and asymmetrical presbyLASIK significantly improved distance UCVA, near UCVA, after 18 months.