Surgical procedures
CORNEA
Surgical procedures were performed by an experienced surgeon (YL). SMILE was performed under topical anesthesia, with the VisuMax 500 kHz femtosecond laser (Carl Zeiss Meditec, Germany). Cap thickness was set at 110–120 μm, cap diameter at 7.0–7.5 mm, and lenticules diameter at 6.0–6.5 mm, with a transition zone of 0.1 mm. A 2 mm side cut incision was made at the 10 o’clock position of the cornea. Cut energy was set at 135 nJ. The stromal lenticules were removed using forceps.FS-LASIK was performed using the VisuMax 500 kHz femtosecond laser (Carl Zeiss Meditec, Germany) for flap creation, and the Schwind Amaris 179 excimer laser (Schwind Eye-Tech-Solutions, Germany) for refractive correction. Flap thickness was set at 90 or 100 μm, flap diameter at 8.5 mm, and hinged at the 12 o’clock position of the cornea. The side cut angle was at 120 degrees.The prescriptions for postoperative management were as follows: tobramycin dexamethasone eye drops (s.a. Alcon-Couvreur n.v.), four times a day for two weeks, deproteinized calf blood extract eye gel (Xingqi pharmaceuticals), once for four weeks, and sodium hyaluronate eye drops, four times a day for four weeks.