Comparison Of Residual Refractive Error And Myopic Regression After Small-Incision Lenticule Extraction (Smile) And Femtosecond Laser-Assisted In Situ Keratomileusis (Fs-Lasik): A Retrospective Cohort Study In Taiwan
Published 2023 - 41st Congress of the ESCRS
Reference: PP03.09 | Type: Free paper | DOI: 10.82333/e9sf-6t32
Authors: I-Hung Lin* 1 , Meng-Yin Lin 2 , Chao-Kai Chang 3
1Department of Ophthalmology,Nobel Eye Institute,Taipei,Taiwan, Province of China;Department of Ophthalmology,Taipei Medical University Hospital,Taipei,Taiwan, Province of China;Graduate institute of clinical medicine, College of Medicine,National Taiwan University,Taipei,Taiwan, Province of China, 2Department of Ophthalmology,Shuang Ho hospital,Taipei,Taiwan, Province of China, 3Department of Ophthalmology,Nobel Eye Institute,Taipei,Taiwan, Province of China
Purpose
To compare the residual refractive error one month after operation and the degree of myopic regression over 12 months post-operation between small-incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK) in Taiwan.
Setting
retrospective cohort study
Methods
Patients with manifest sphere refraction of -1.00 to -12.00 D myopia in Taiwan were recruited. Total of 530 eyes of 530 patients who received FS-LASIK(mean age of 32.4 ± 7.8; mean manifest refraction spherical equivalent (SE) of -7.47 ± 2.67 D) and 530 eyes of 530 patients who received SMILE(mean age of 32.0 ± 7.3; mean manifest refraction SE of -7.46 ± 2.29 D) were matched 1:1 based on age and refraction. The refractive outcomes at post-operation one, 3, 6, 9, and 12 months were recorded. The degree of myopic regression was defined as the difference of myopia degree between post-operation one and other months. Predictors affecting residual refractive error and myopic regression were estimated with a Cox proportional hazard (Cox PH) model.
Results
At post-operation one month, the residual refractive error was greater in the SMILE group than in the FS-LASIK group(-0.77 D vs -0.405 D, p<0.0001). The degree of myopic regression was similar between the SMILE group and the FS-LASIK group at post-operation 3 months(increased -0.123 D vs increased -0.126 D, p= 0.23) and 6 months(increased -0.176 D vs increased -0.167 D, p= 0.31). But it was less in the SMILE group than in the FS-LASIK group at post-operation 9 months(increased -0.191 D vs increased -0.298 D, p=0.039), and 12 months(increased -0.043 D vs increased -0.215 D, p=0.004). Multivariate analysis of the Cox PH model revealed that preoperative manifest SE(P=0.0008) and flap diameter(P=0.012) were also predictors of myopic regression.
Conclusions
At post-operation one month, the residual refractive error was greater in the SMILE group than in the FS-LASIK group. The degree of myopic regression was similar in both groups from post-operation 3 month to 6 months, but was less in the SMILE group than in the FS-LASIK group from post-operation 9 month to 12 months. Manifest SE and flap diameter were also predictors of myopic regression.