Femtosecond laser corneal refractive surgery for the correction of high myopic anisometropic amblyopia in juveniles

AIM: To evaluate the effects of femtosecond laser-assisted in situ keratomileusis (FS-LASIK) and small-incision lenticule extraction (SMILE) to correct high myopic anisometropic amblyopia in juvenile patients. METHODS: From November 2013 to January 2015, 33 amblyopic patients with high myopic anisometropic amblyopia were studied. FS-LASIK (30 eyes) or SMILE (3 eyes) was performed in the amblyopic eyes. Visual acuity, refraction, contrast sensitivity, stereoacuity and complications were evaluated. Patients completed follow-up examinations at 3d, 1mo, 3mo and the last follow-up time (mean 8.17 +/- 3.23mo) after surgery. RESULTS: The mean age at surgery was 9.04 +/- 3.04y (range 6-16y). The mean spherical equivalent in the amblyopic eyes was significantly decreased from -10.00 +/- 2.39 D preoperatively to -0.06 +/- 1.06 D at 1mo, -0.19 +/- 1.33 D at 3mo and -0.60 +/- 1.43 D at approximately 8mo postoperatively (P< 0.05 for all). The mean myopic anisometropia was significantly decreased from -9.45 +/- 2.33 D preoperatively to + 0.37 +/- 1.48 D at 1mo, -0.46 +/- 1.47 D at 3mo and -0.09 +/- 1.83 D at approximately 8mo (P< 0.05 for all). The logarithm of the minimum angle of resolution (logMAR) for uncorrected and corrected distance visual acuity (UDVA and CDVA, respectively) of the amblyopic eye improved from 1.74 +/- 0.35 and 0.98 +/- 0.63 preoperatively to 0.45 +/- 0.31 and 0.41 +/- 0.33 at approximately 8mo after surgery, respectively. The logMAR CDVA at 3d, 1, 3 and 8mo postoperatively improved by means of 1.42, 2.22, 2.96, and 4.39 lines, and a gain of more than two lines accounted for 45%, 50%, 74% and 86% of all patients, respectively. The contrast sensitivity of both amblyopic eyes and dominant eyes at 0.5, 2, 8 cycles per degree was significantly improved postoperatively (P< 0.05 for all). Of the 33 pediatric patients, no patients had near stereopsis preoperatively and seven patients (21.2%) recovered near stereopsis (400 '' to 60 '') at approximately 8mo after surgery. No intraoperative or postoperative complications occurred in any patient. CONCLUSION: FS-LASIK or SMILE can be promising alternative methods to correct high myopic anisometropic amblyopia in juvenile patients who have failed with traditional approaches.