Korean J Ophthalmol.  2022 Jun;36(3):202-209. 10.3341/kjo.2021.0154.

The Impact of Learning Curve on Flap Thickness Outcome in Femtosecond Laser-assisted Laser In Situ Keratomileusis Performed with New LenSx Dual Platform

• Asena BS
• Donmez O

• KMID: 2530586
• DOI: http://doi.org/10.3341/kjo.2021.0154

Abstract

Purpose
To evaluate the effect of learning curve on flap thickness (FT) outcome in femtosecond (FS) laser-assisted laser in situ keratomileusis (LASIK) operation for myopia performed with recently introduced LenSx dual platform using curved applanation cone.
Methods
Seventy eyes of 36 patients with myopia or myopic astigmatism operated with FS laser-assisted LASIK with recently introduced LenSx dual platform were evaluated in this retrospective study. Operations were divided into two groups: first 20 operations (20 eyes of 10 patients) and next 50 operations (50 eyes of 26 patients). Data on patient demographics, preoperative and postoperative keratometric and aberrometric parameters, and FT related outcome, including mean central FT, mean total FT, intra-FT range, and FT homogeneity were compared in study groups.
Results
Except for significantly lower preoperative steepest keratometry values in the next 50 operations versus first 20 operations (p = 0.033), no significant difference was noted between study groups in terms of preoperative and postoperative parameters. When compared to first 20 operations, next 50 operations were associated with significantly higher values for mean central FT (median, 123 µm vs. 114 µm; p = 0.007) and mean total FT (median, 123 µm vs. 113 µm; p = 0.015), whereas significantly lower intra-FT range (median, 4.0 µm vs. 4.5 µm; p = 0.003).
Conclusions
In conclusion, our findings related to FS laser-assisted LASIK surgery for myopia with new LenSx dual platform using curved applanation cone revealed significant impact of learning curve on the corneal FT outcome in terms of closer FT to the intended value and lower intra-flap range.

Keyword

Laser keratomileusis; LenSx; Learning curve; Surgical flap