Abstract
<title>Abstract</title> <p>Background Early refractive recovery after femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) may be more variable in hyperopic eyes than in myopic eyes. In patients with mixed anisometropia, the two eyes have different refractive characteristics, and postoperative recovery may not be synchronous. We report a case of transient myopic-like shift in the hyperopic eye with asynchronous bilateral visual recovery after FS-LASIK for mixed anisometropia. Case report An 18-year-old male had preoperative cycloplegic refraction of -5.25 DS/-0.50 DC × 176° in the right eye and + 0.75 DS/+1.25 DC × 95° in the left eye, indicating myopic astigmatism in the right eye, hyperopic astigmatism in the left eye, and mixed anisometropia. He underwent uneventful bilateral FS-LASIK. The planned flap thickness was 110 µm in both eyes, with an expected ablation depth of 94 µm in the right eye and 33 µm in the left eye. Early postoperative Pentacam examination showed no obvious decentered ablation, severe irregular astigmatism, or ectatic change. On postoperative day 4, uncorrected distance visual acuity was 1.0 in the right eye and 0.5 in the left eye. Manifest refraction in the left eye was − 1.00 DS, whereas cycloplegic refraction was + 0.25 DS/-0.50 DC × 001°, with best-corrected visual acuity improving to 1.0. After short-acting cycloplegic treatment, reduced near work, and accommodative relaxation training, visual acuity in the left eye gradually improved. At 1 and 2 months postoperatively, uncorrected distance visual acuity was 1.0 in both eyes. The patient was lost to follow-up after 2 months. Conclusions Asynchronous visual recovery may occur after FS-LASIK in patients with mixed anisometropia. When slow visual recovery or a myopic-like shift occurs in the hyperopic eye during the early postoperative period, cycloplegic refraction, surgical parameters, corneal tomography, and follow-up changes should be considered together. In patients with a clear discrepancy between manifest and cycloplegic refraction and no obvious abnormality in corneal morphology, undercorrection, refractive regression, or the need for retreatment should not be judged prematurely based only on a single early manifest refraction result.</p>