Elliptical ELSA (LASEK) instruments for the treatment of astigmatism

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 × 8.0 mm) with a 70 μm calibrated blade and an elliptical alcohol cone (11.5 mm × 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.