[Experience with Introduction of SMILE: Learning Phase of our First 200 Treatments]. / Erfahrung bei der Einführung von SMILE: Lernkurve der ersten 200 Behandlungen.

ABSTRACT

Background Small Incision Lenticule Extraction (SMILE) is a relatively new surgical method to correct myopia and myopic astigmatism. Although considered to be safe and effective, it is not yet popular. Potential reasons for its limited use could be that surgeons fear inferior results and a higher complication rate in the learning phase. Therefore we present our experiences with the treatment of our first 200 eyes, with special attention to refraction results, complications, and learning curve. Patients and Methods 200 myopic or myopic astigmatic eyes of 102 patients were treated with SMILE. The analysis was separated into two phases Phase I (first 100 treatments) with large variation of laser parameters and surgical technique, phase II (second 100 treatments) with mostly constant laser parameters and identical surgical technique. Results Phase I showed the following 3-month results after a mean attempted correction of - 5.70 ± 2.54 D (range - 1.25 to - 10.00 D) spherical equivalent - 0.03 ± 0.46 D, astigmatism - 0.34 ± 0.35 D, uncorrected distance visual acuity 1.02, corrected distance visual acuity (CDVA) 1.22. Postoperative and preoperative CDVA did not differ (p = 0.71). Mean refraction reached the targeted value after 5 days. Efficacy index was 0.55 ± 0.19 at day 1, 0.67 ± 0.22 at day 5, and 0.87 ± 0.23 at 3 months. In Phase II, the efficacy index improved to 0.63 ± 0.25 (p = 0.039) at day 1 and to 0.75 ± 0.26 (p = 0,02) at day 5. The most frequent complications were intraoperative abrasions and epithelial cells in the interface. Almost all complications occurred less frequently in Phase II. Conclusion Our first SMILE treatments showed very good refractive predictability, very good safety and rapid visual recovery. Results after high myopic corrections were equivalent to or better than our first Femto-LASIK treatments. We had a much higher complication rate than with our LASIK treatments - that have been established over several years. All complications could be managed without loss of visual acuity. Visual recovery was faster and complications less frequent with experience gained. SMILE has replaced LASIK as our preferred treatment modality for the correction of myopic astigmatic eyes.