Safety and complications of more than 1500 small-incision lenticule extraction procedures.

PURPOSE: To evaluate the safety and complications of small-incision lenticule extraction (SMILE). DESIGN: Clinical control cohort study. PARTICIPANTS: A total of 922 healthy patients (1800 eyes) who were treated for myopia or myopic astigmatism between January 2011 and March 2013 at the Department of Ophthalmology, Aarhus, Denmark. METHODS: Patients received a full preoperative examination and were treated with SMILE in both eyes and followed for 3 months (1574 eyes). Patients with complications, including loss of corrected distance visual acuity (CDVA) or dissatisfaction, were offered a late reexamination. MAIN OUTCOME MEASURES: Surgical complications and CDVA. RESULTS: Mean preoperative spherical equivalent refraction was -7.25±1.84 diopters (D). Average postoperative refraction was -0.28±0.52 D, and mean error of treatment was -0.15±0.50 D. By 3 months, 86% (1346 eyes) had unchanged or improved CDVA. A loss of 2 or more lines was observed in 1.5% of eyes; however, at a late follow-up visit (average, 18 months), CDVA was within 1 line of the preoperative level in all eyes. Perioperative complications included epithelial abrasions (6%), small tears at the incision (1.8%), and difficult lenticule extraction (1.9%). The cap was perforated in 4 eyes, and a major tear occurred in 1 eye; however, none of these patients had late visual symptoms. In 0.8% (14 eyes), suction was lost during surgery. Re-treatment was successful in 13 eyes, whereas 1 eye had ghost images and was re-treated with topography-guided photorefractive keratectomy (PRK). Postoperative complications included trace haze (8%), epithelial dryness on day 1 (5%), interface inflammation secondary to central abrasion (0.3%), and minor interface infiltrates (0.3%); these complications had an impact on CDVA at 3 months in only 1 case. Irregular corneal topography occurred in 1.0% of eyes, resulting in reduced 3-month CDVA (12 eyes) or ghost images (6 eyes). Topography-guided PRK was performed in 4 eyes, with improvement in 3 cases. Satisfaction was high, with only 2 patients dissatisfied at their latest visit because of blurred vision or residual astigmatism. CONCLUSIONS: Overall, SMILE had acceptable safety. Although 1.5% of eyes had reduced CDVA by 3 months, visual acuity was restored in the long term. Likewise, patient satisfaction was high.

Femtosecond (FS) laser vision correction procedure for moderate to high myopia: a prospective study of ReLEx(®) flex and comparison with a retrospective study of FS-laser in situ keratomileusis.

PURPOSE: To present our initial clinical experience with ReLEx(®) flex (ReLEx) for moderate to high myopia. We compare efficacy, safety and corneal higher-order aberrations after ReLEx with femtosecond laser in situ keratomileusis (FS-LASIK). METHODS: Prospective study of ReLEx compared with a retrospective study of FS-LASIK. ReLEx is a new keratorefractive procedure, where a stromal lenticule is cut by a femtosecond laser and manually extracted. Forty patients were treated with ReLEx on both eyes. A comparable group of 41 FS-LASIK patients were retrospectively identified. Visual acuity, spherical equivalent (SE) and corneal tomography were measured before and 3 months after surgery. RESULTS: Preoperative SE averaged -7.50 ± 1.16 D (ReLEx) and -7.32 ± 1.09 D (FS-LASIK). For all eyes, mean corrected distance visual acuity remained unchanged in both groups. For eyes with emmetropia as target refraction, 41% of ReLEx and 61% of FS-LASIK eyes had an uncorrected distance visual acuity of logMAR ≤ 0.10 at day 1 after surgery, increasing to, respectively, 88% and 69% at 3 months. Mean SE was -0.06 ± 0.35 D 3 months after ReLEx and -0.53 ± 0.60 D after FS-LASIK. The proportion of eyes within ±1.00 D after 3 months was 100% (ReLEx) and 85% (FS-LASIK). For a 6.0-mm pupil, corneal spherical aberrations increased significantly less in ReLEx than FS-LASIK eyes. CONCLUSIONS: ReLEx is an all-in-one femtosecond laser refractive procedure, and in this study, results were comparable to FS-LASIK. Refractive predictability and corneal aberrations at 3 months seemed better than or equal to FS-LASIK, whereas visual recovery after ReLEx was slower.

Predictors for the outcome of small-incision lenticule extraction for Myopia.

PURPOSE: To study the influence of patient- and surgery-related parameters on the predictability, efficacy, and safety of small-incision lenticule extraction (SMILE) for treatment of myopia. METHODS: This prospective, clinical quality, control study comprised 670 eyes from 335 patients with myopia up to -10.00 diopters (D) (spherical equivalent refraction) and astigmatism up to 2.00 D treated with SMILE in both eyes and followed for 3 months. RESULTS: Preoperative mean spherical equivalent refraction was -7.19±1.30 D. In eyes with emmetropia as the target refraction, 84% obtained uncorrected distance visual acuity ≤ 0.10 logMAR (20/25 or better Snellen equivalent) at 3 months. Mean corrected distance visual acuity (CDVA) improved from -0.03 to -0.05 logMAR (P<.01). Two or more lines of CDVA were lost in 2.4% (16 eyes). The achieved refraction was 0.25±0.44 D less than attempted after 3 months, and 80% (537 eyes) and 94% (631 eyes) were within ±0.50 and ±1.00 D of attempted correction, respectively. Multiple linear regression analyses revealed that spherical equivalent refraction undercorrection was predicted by increasing patient age (0.10 D per decade; P<.01) and steeper corneal curvature (0.04 D per D; P<.01). Safety and efficacy of the procedure were minimally affected by age, gender, and simultaneous cylinder correction. CONCLUSIONS: Undercorrection of 0.25 D and small effects of patient age and corneal curvature suggest that the standard nomogram for SMILE need only minor adjustments. This study suggests that safety and efficacy are not influenced to any clinically significant degree by easily discernible patient factors.

Small-incision lenticule extraction for moderate to high myopia: Predictability, safety, and patient satisfaction.

PURPOSE: To present initial clinical experience with small-incision lenticule extraction for the treatment of moderate to high myopia. SETTING: Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark. DESIGN: Prospective clinical study. METHODS: For small-incision lenticule extraction, an intrastromal lenticule was cut with a femtosecond laser and manually extracted without creation of a flap. Patients were treated and followed for 3 months. Only 1 randomly chosen eye of each patient was used in the statistical analyses. RESULTS: The study enrolled 144 patients. The mean preoperative spherical equivalent was -7.18 diopters (D) ± 1.57 (SD). Of eyes with emmetropia as target refraction, 40% had an uncorrected distance visual acuity of 0.1 logMAR or less 1 day after surgery; this increased to 73% at 3 months. The mean corrected distance visual acuity (CDVA) improved significantly from -0.01 (logMAR) preoperatively to -0.03 3 months postoperatively. None of the 127 eyes lost 2 lines or more of CDVA and 6 eyes lost 1 line of CDVA after 3 months. In contrast, 1 eye gained 2 lines and 24 eyes gained 1 line of CDVA. The achieved refraction was a mean of -0.09 ± 0.45 D from the attempted refraction. Of the eyes, 77% were within ±0.50 D and 95% were within ±1.00 D. Ninety-five percent of the patients would recommend the procedure to others. CONCLUSIONS: The refractive predictability, safety, and patient satisfaction 3 months after small-incision lenticule extraction were high and comparable to results in previous studies of femtosecond laser-assisted techniques. FINANCIAL DISCLOSURE: Drs. Hjortdal and Asp received travel reimbursement from Carl Zeiss Meditec AG, Jena, Germany. No other author has a financial or proprietary interest in any material or method mentioned.