Abstract:  Objective To analyze the therapeutic effect of astigmatism with moderate and high myopia by small incision lenticule extraction (SMILE) and investigate the characteristics of SMILE. Design  Prospective case series. Participants  A total of 47 patients (92 eyes) with moderate and high myopic astigmatism (-1.00 D~-5.50 D). Methods A total of 47 patients (92 eyes) with moderate and high myopic astigmatism (astigmatism≥-1.00 D) were treated by SMILE, which were divided into two groups. Group A included 54 eyes with moderate astigmatism (-1.00 D~-3.00 D),  group B 38 eyes with high astigmatism (-3.00 D~-4.50 D). The operation were carried with the VisuMax femtosecond laser. Intended flap diameters were 6.8~7.5 mm, cap with 120~130 μm， side cutting 2 mm, according to the normal operation of SMILE. Main Outcome Measures Preoperative best corrected visual acuity（BCVA），uncorrected visual acuity (UCVA), refraction, keratometry, residual astigmatism and visual contrast sensitivity at 1 day， 1 week， 1 month and 6 months after surgery. Results There were 92 eyes completed the procedure as designed, including 1 eye with negative pressure cone ring detached during the procedure, then absorbed again to complete the surgery. In three cases, air bubble was found between corneal lens layers. Corneal cap edge (epithelium loss was greater than 1 mm × 1 mm in 2 eyes. Laser scanning area shading resulted in difficult separation in 1 eye. No other complications were encountered. No microperforations were observed, and neither graft rejection nor failure occurred. Cornea was transparent and no epithelial defect and dry spot were observed in patients 1 day after surgery. Postoperative UCVA was greater than or equal to the preoperative BCVA in 89, 90, 92, 79 eyes respectively at 1 d, 1 wk, 1 mo and 6 mo as after surgery(only 79 eyes were followed at 6 mo). Furthermore post operation visual acuity improved more than 2 rows than preoperative BCVA was found in  14, 18, 22, 16 eyes at 1 d, 1 wk, 1 mo and 6 mo follow up respectively. No case with DLK,  epithelial implantation and obvious dry eye symptoms was found. There was no significant difference in UCVA after surgery between moderate and high astigmatism group. Conclusion SMILE operation could provide good clinical efficacy, safety and relatively good predictability in the correction of moderate and high myopic astigmatism. (Ophthalmol CHN, 2014, 23: 295-300)

Key words: total resection of femtosecond micro lens, myopia and astigmatism, water separation, center location