Yishan Qian1, Jia Huang1, Renyuan Chu1, Jing Zhao1, Meiyan Li1, Xingtao Zhou2, Emily Olszewski1, Yutung Wang1. 1. From the Department of Ophthalmology, Eye and ENT Hospital, Fudan University, and the Key Laboratory of Myopia of State Health Ministry (Qian, Huang, Chu, Zhao, Li, Zhou), Shanghai, China; the Department of Surgery (Olszewski), Division of Otolaryngology-Head and Neck Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, and Johns Hopkins University School of Medicine (Wang), Baltimore, Maryland, USA. 2. From the Department of Ophthalmology, Eye and ENT Hospital, Fudan University, and the Key Laboratory of Myopia of State Health Ministry (Qian, Huang, Chu, Zhao, Li, Zhou), Shanghai, China; the Department of Surgery (Olszewski), Division of Otolaryngology-Head and Neck Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, and Johns Hopkins University School of Medicine (Wang), Baltimore, Maryland, USA. Electronic address: xingtaozhou@163.com.
Abstract
PURPOSE: To evaluate the influence of the origin of astigmatism on the correction of myopia or myopic astigmatism by femtosecond laser small-incision lenticule extraction (SMILE). SETTING: Ophthalmology Department, Eye and ENT Hospital, Shanghai, China. DESIGN: Prospective case series. METHODS: Small-incision lenticule extraction was performed to correct myopia or myopic astigmatism. Ocular residual astigmatism (ORA) was determined by vector analysis using manifest refraction and Scheimpflug camera imaging of the anterior cornea. Patients were divided into 2 groups according to ORA (high >1.0 diopter [D]; low ≤1.0 D), and procedural efficacy was compared. Patients were examined preoperatively and 1, 3, and 6 months postoperatively. RESULTS: This study comprised 122 right eyes of 122 patients. No significant difference was found in the preoperative manifest astigmatism (target-induced astigmatism [TIA]) between the low ORA group (n = 67) and high ORA group (n = 55). The mean postoperative manifest astigmatism was higher in the high ORA group at all postoperative timepoints (1 month: t = 2.182, P=.031; 3 months: t = 2.30, P=.023; 6 months: t = 2.193, P=.03). The mean index of success (postoperative astigmatism/TIA) was 0.68 in the high ORA group and 0.34 in the low ORA group 1 month postoperatively (t = 2.531, P=.013); 0.73 and 0.39, respectively, at 3 months (t = 2.689, P=.008); and 0.77 and 0.46, respectively, at 6 months (t = 2.105, P=.037). CONCLUSION: Small-incision lenticule extraction was effective in correcting astigmatism but may be less effective in correcting ORA.
PURPOSE: To evaluate the influence of the origin of astigmatism on the correction of myopia or myopic astigmatism by femtosecond laser small-incision lenticule extraction (SMILE). SETTING: Ophthalmology Department, Eye and ENT Hospital, Shanghai, China. DESIGN: Prospective case series. METHODS: Small-incision lenticule extraction was performed to correct myopia or myopic astigmatism. Ocular residual astigmatism (ORA) was determined by vector analysis using manifest refraction and Scheimpflug camera imaging of the anterior cornea. Patients were divided into 2 groups according to ORA (high >1.0 diopter [D]; low ≤1.0 D), and procedural efficacy was compared. Patients were examined preoperatively and 1, 3, and 6 months postoperatively. RESULTS: This study comprised 122 right eyes of 122 patients. No significant difference was found in the preoperative manifest astigmatism (target-induced astigmatism [TIA]) between the low ORA group (n = 67) and high ORA group (n = 55). The mean postoperative manifest astigmatism was higher in the high ORA group at all postoperative timepoints (1 month: t = 2.182, P=.031; 3 months: t = 2.30, P=.023; 6 months: t = 2.193, P=.03). The mean index of success (postoperative astigmatism/TIA) was 0.68 in the high ORA group and 0.34 in the low ORA group 1 month postoperatively (t = 2.531, P=.013); 0.73 and 0.39, respectively, at 3 months (t = 2.689, P=.008); and 0.77 and 0.46, respectively, at 6 months (t = 2.105, P=.037). CONCLUSION: Small-incision lenticule extraction was effective in correcting astigmatism but may be less effective in correcting ORA.