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Published on: September 20, 2024
Elliptical ELSA (LASEK) instruments for the treatment of astigmatism
Chris P Lohmann1, Christoph Winkler von Mohrenfels, Wolfgang Herrmann
1From University Eye Clinic Regensburg, Regensburg, Germany. lohmann@eye-regensburg.de
Purpose:
To investigate newly designed, elliptical ELSA (excimer laser subepithelial ablation) instruments for the treatment of astigmatism.
Setting:
University Eye Clinic Regensburg, Regensburg, Germany, and the Rayne Institute, Department of Ophthalmology, St. Thomas' Hospital, London, United Kingdom.
Methods:
The new ELSA instrument set consists of an elliptical microtrephine (11.0 mm x 8.0 mm) with a 70 microm calibrated blade and an elliptical alcohol cone (11.5 mm x 8.5 mm). With this instrument set, ELSA (the laser-assisted subepithelial keratectomy [LASEK] described by Camellin) was performed in 34 astigmatic eyes. The cylindrical correction was between 1.00 diopters (D) and 3.50 D and the spherical correction, between -0.75 D and -8.75 D. In all eyes, the follow-up was 6 months. The postoperative refractive outcome was analyzed using Alpins vector analysis.
Results:
Excimer laser subepithelial ablation was performed without intraoperative complications in all eyes. At 6 months, the mean spherical correction was -0.04 D +/- 0.27 (SD) (range +0.75 to -0.75 D) and the mean cylindrical correction, 0.27 +/- 0.23 D (range 0 to 0.75 D). The mean index of success was 0.18 +/- 0.15.
Conclusions:
With the elliptical instruments, ELSA was an effective and safe surgical procedure for astigmatism.
