Posters

Comparision of refractive outcome and higher order aberration (HOA) in photorefractive keratectomy (PRK) and small incision lenticule extraction (ReLEx SMILE) in myopic eyes

Poster Details

First Author: S.Aimprapai THAILAND

Co Author(s):    P. Chantaren   L. Pariyakanok   V. Puangsricharern   N. Kasetsuwan   U. Reinprayoon   V. Satitpitakul     

Abstract Details

Purpose:

To compare refractive outcome and higher order aberration between photorefractive keratectomy (PRK) and small Incision lenticule extraction (ReLEx SMILE) in myopic patients at 12 months postoperatively.

Setting:

Refractive surgery department of Chulalongkorn Hospital, Bangkok, Thailand

Methods:

Retrospective chart review of 95 eyes of 53 patients underwent PRK and 95 eyes of 69 patients underwent ReLEx SMILE. Baseline characteristic of both groups were matched based on preoperative spherical and cylindrical errors.The primary outcome were refractive efficacy, safety, predictability, stability and mean change from preoperative to postoperative HOA. The HOA was measured using Wavefront Supported Custom Ablation (WASCA) aberrometer (Carl Zeiss Meditec AG, Jena, Germany) at 6 mm. zone. Generalized Estimated Equation was used to compare normally distributed data between groups, determined by mean, standard deviation and 95% confident interval. Statistical significance was determined at p-value <0.05.

Results:

The mean preoperative spherical equivalent (SE) was -2.848 ± 0.921 (-1.00 to -5.00 diopters) in PRK group and -3.34 ± 0.882 (-1.25 to -5.625 diopters) in ReLEx SMILE group. At 12 month, the mean postoperative SE was -0.441 ± 0.349 in PRK and -0.285 ± 0.375 in ReLEx SMILE respectively (95%CI -0.288 to -0.010, P = 0.035). The efficacy index and safety index in PRK vs ReLEx SMILE group were 1.347± 0.72 vs 1.051± 0.313, 95%CI 0.095 to 0.498, p = 0.004 and 1.37 ± 0.701 vs 1.059 ± 0.304, 95%CI 0.115 to 0.505, p = 0.002 respectively. No statistically significant difference was found between predictability and stability in each groups. Mean change of HOA in PRK vs ReLEx SMILE group was 2.635 vs 3.569 (95%CI 0.260 to 1.357, P = 0.004) for total HOA, -0.116 vs 0.123 (95%CI -0.344 to -0.112, P <0.001) for spherical aberration, 0.123 vs 0.437 (95%CI -0.490 to -0.110, P = 0.002) for horizontal coma and 0.014 vs 0.092 (95%CI -0.231 to -0.008, P = 0.036) for trefoil 30 aberration. No statistically significant difference was found in HOA, trefoil 0, vertical coma between each group.

Conclusions:

Efficacy index, safety index, mean change in total HOA, spherical, horizontal coma, trefoil 30 aberration were statistically different in PRK and SMILE in eyes with low myopia (≤ -6.00D).

Financial Disclosure:

None