Introduction
Methods
Results
Author (year) | Location | Subjects | Summary of findings |
---|---|---|---|
Visual outcome | |||
Kataoka et al. [7] | Japan | 34 SMILE-treated eyes of 23 patients and 34 LASIK-treated eyes of 24 patients (mean preoperative MRSE ± SD: −4.69 ± 0.6 D and −4.67 ± 0.64 D, respectively) | No significant differences in postoperative UDVA and CDVA between the two groups; comparable effectiveness and safety profiles SMILE achieved higher refractive power correction in the peripheral cornea than LASIK |
Moshirfar et al. [8] | USA | 68 SMILE-treated eyes of 35 patients (preoperative manifest sphere and cylinder ranged from −7.50 D to −2.75 D and −0.75 D to 0.00 D, respectively) | Visual outcomes for SMILE were superior to first-generation LASIK [SVS Apex Plus, VISX STAR S2, Nidek EC-5000 (2000)] from 1999 to 2000, but inferior to the latest generation [Nidek EC-5000 (2013), Alcon Contoura, VISX iDesign] from 2013 to 2016, in terms of percentage of patients with 20/20 UDVA or better |
Chen et al. 2017 | China | 65 myopic eyes of 38 patients treated with SMILE (preoperative MSE ± SD: −5.53 ± 1.24D) or WFG FS-LASIK (preoperative MSE ± SD: −5.54 ± 2.40 D) | No significant differences in visual outcomes (UDVA and CDVA) between WGF LASIK and SMILE No significant differences in overall postoperative ocular aberrations trefoil, horizontal coma, spherical aberration, or total HOAs Higher vertical coma values in the SMILE group (0.163 ± 0.093) than the WFG FS-LASIK group (0.116 ± 0.077) |
El-Mayah et al. [10] | Egypt | 30 SMILE-treated eyes and 30 FS-LASIK-treated eyes with myopia or myopic astigmatism (mean preoperative MRSE ± SD: −4.17 ± 1.86 D and −3.97 ± 2.02 D, respectively) | No significant differences in CDVA between the two procedures 3 months postoperatively Similar mean safety and efficacy indices (SMILE: 1.1060.14, 1.0260.17; FS-LASIK: 1.1260.15, 1.0760.20) Refraction was within ± 0.5 D of target refraction in 93% of treated eyes in both groups No significant differences in changes in postoperative higher-order RMS (P1/40.2000), primary coma RMS (P1/40.0589) and spherical aberrations (P1/40.0543) SMILE induced less effect on dry eye parameters 3 months postoperatively |
Pietila et al. [11] | Finland | 100 SMILE-treated eyes (preoperative MSE ± SD: −1.38 to −8.25 D) and 200 FS-LASIK-treated eyes (preoperative MSE ± SD: −0.63 to −11.63 D) | Comparable safety, efficacy and predictability SMILE group had more postoperative astigmatism than the FS-LASIK-treated group Decrease in dry eye symptoms in SMILE-treated eyes 1 month postoperatively (P = 0.01) but not in FS-LASIK-treated eyes (P = 0.87) compared with the preoperative situation |
Liu et al. [12] | China | 113 SMILE-treated eyes (MSE ± SD: −5.22 ± 1.70 D) and 84 FS-LASIK-treated eyes (MSE ± SD: −5.18 ± 1.93 D) | Comparable visual outcomes in correcting myopia and myopic astigmatism Slower recovery in visual acuity in SMILE-treated eyes |
Lin et al. [13] | China | 60 SMILE-treated eyes of 31 patients (MSE ± SD: −5.13 ± 1.75 D) and 51 FS-LASIK-treated eyes of 27 patients (MSE ± SD: −5.58 ± 2.41 D) | Comparable safety, efficacy and predictability Lower HOAs and spherical aberrations in SMILE-treated eyes than FS-LASIK-treated ones at 1 month (P = 0.007, 0.000) and 3 months (P = 0.006, 0.000) postoperatively |
Chiche et al. [14] | France | 46 eyes of 23 patients for each group (MSE for SMILE group ± SD: −4.45 ± 1.93D; MSE for LASIK group ± SD: −3.63 ± 1.96 D) | Slower corneal optical recovery after SMILE (postoperative contrast sensitivity in the LASIK group was superior at 1 day (P = 0.014) and 7 days (P = 0.001) but comparable to the SMILE group at 1 month) |
Xia et al. [16] | China | 78 SMILE-treated eyes (SE ± SD: −8.11 ± 1.09 D) and 65 WFG FS-LASIK-treated eyes (SE ± SD: −8.05 ± 1.12 D) | Comparable efficacy and safety profile in correcting high myopia and myopic astigmatism Lower OSDI scores and longer TBUT in SMILE-treated eyes at 1 month and 3 months postoperatively, but no significant difference in mean OSDI scores between the two groups later throughout the 3-year follow up (P > 0.05) |
Jin et al. [17] | China | 165 SMILE-treated eyes of 86 patients with high myopia (SE ± SD: 7.16 ± 0.93 D) and mild-to-moderate myopia (SE ± SD: −4.34 ± 0.97 D) | SMILE showed good efficacy and safety profiles in the correction of mild, moderate and high myopia A trend towards undercorrection by SMILE in highly myopic eyes (> −6.00 D) |
Kim et al. [18] | Korea | 183 SMILE-treated eyes of 92 patients with high myopia (preoperative SE ± SD: −7.67 ± 1.01 D) and mild-to-moderate myopia (SE ± SD: −5.05 ± 0.71 D) | SMILE showed good efficacy and safety profiles in the correction of mild, moderate and high myopia [comparable efficacy and safety 12 months postoperatively (p = 0.141 and p = 0.307)] |
Ganesh et al. [19] | India | 30 eyes with low to moderate myopic astigmatism (SE: −3 to −8 D) undergoing T-ICL, FS-LASIK or ReLEx SMILE) | No significant difference in surgically induced astigmatism (SIA) between the two techniques (LASIK: 1.21 ± 0.85; SMILE: 1.02 ± 0.43; P > 0.05) Significant increase in HOAs in LASIK patients at 1 year postoperatively (0.163 ± 0.14µ) compared with preoperative values (0.115 ± 0.05µ), but nonsignificant in the SMILE group (0.126 ± 0.07µ at 1 year and 0.120 ± 0.06µ preoperatively) Higher postoperative TBUT scores (SMILE: 10.7 ± 1.08 s; LASIK: 9.4 ± 1.47 s) and greater patient satisfaction in the SMILE group |
Jin et al. [20] | China | 63 SMILE-treated eyes (mean MRSE ± SD: −5.55 ± 1.23D) and 61 FS-LASIK-treated eyes (mean MRSE ± SD: −5.84 ± 1.90 D) | At a smaller pupil diameter (3 mm), the two techniques showed similar improvement in optical quality 3 months postoperatively in terms of modulation transfer function (MTF) and point spread function (PSF) At a larger pupil diameter (6 mm), SMILE-treated eyes had significantly better optical quality than FS-LASIK |
Lazaridis et al. [21] | Germany | 58 myopic eyes for each group (preoperative MSE for SMILE group ± SD: −5.76 ± 1.80 D; MSE for FS-LASIK group ± SD: −5.03 ± 2.32 D) | No significant differences in 3-month postoperative CDVA (1.04 ± 0.16 for SMILE; 1.05 ± 0.13 for LASIK) or corneal clarity evaluated using Scheimpflug corneal densitometry (17.1 ± 1.1 for SMILE; 17.4 ± 1.1 for LASIK) |
Higher-order aberrations | |||
Han et al. [22] | China | 34 SMILE-treated eyes of 34 patients and 40 FS-LASIK-treated eyes of 40 patients | No significant difference in corneal backscatter between SMILE and LASIK groups (both P > 0.05) |
Ganesh and Gupta [24] | India | 50 SMILE-treated eyes (preoperative MSE ± SD: −4.95 ± 2.09 D) and 50 LASIK-treated eyes (preoperative MSE ± SD: −3.54 ± 2.26 D) | Significantly fewer cases of aberrations in the SMILE group (0.267 + 0.07 pm) than in the LASIK group (0.437 + 0.103 pm, P < 0.001) 3 months postoperatively Significantly more common postoperative dry eye symptoms following LASIK (P < 0.001) |
Ye et al. [25] | China | 82 LASIK-treated eyes, 119 WF-LASIK-treated eyes, 88 FS-LASIK-treated and 170 SMILE-treated eyes (preoperative MSE ± SD for LASIK, WF-LASIK, FS-LASIK and SMILE: −4.91 ± 1.81, −4.82 ± 1.55, −5.43 ± 2.32, and −5.03 ± 1.89, respectively) | SMILE induced fewer total HOAs and spherical aberration compared with LASIK and FS-LASIK 6 months postoperatively |
Corneal sensation | |||
Xia et al. [15] | China | 69 SMILE-treated eyes of 35 patients (SE ± SD: −5.04 ± 2.32 D) and 59 FS-LASIK-treated eyes of 30 patients (SE ± SD: −5.13 ± 1.36 D) | Central corneal sensation values in the FS-LASIK group showed significant decreases at 1 week, 1 month, 3 months and 6 months postoperatively compared with preoperative values; no significant changes in the SMILE group OSDI scores were significantly higher in the FS-LASIK group than in the SMILE group at the 6-month follow-up (p = 0.000) |
Wei and Wang [26] | China | 61 SMILE-treated myopic eyes (mean preoperative sphere ± SD: −5.11 ± 1.25 D) and 54 LASIK-treated eyes (mean preoperative sphere ± SD: −5.50 ± 1.54 D) | Significantly higher corneal sensitivity in SMILE group than in LASIK group for all quadrants of the cornea (central, superior, inferior, nasal and temporal) at 1 week and 1 and 3 months postoperatively, indicating faster recovery in corneal sensitivity following SMILE |
Li et al. [27] | China | 32 SMILE-treated eyes (mean preoperative SE ± SD: −6.56 ± 1.28 D) of 18 patients and 42 FS-LASIK-treated eyes of 22 patients (mean preoperative SE ± SD: −8.46 ± 2.15 D) | At 1 week and 1 and 3 months postoperatively, SMILE group showed smaller decreases (7608.3 ± 576.6, 7642.1 ± 564.6 and 6736.0 ± 644.0 µm/mm2, respectively) in subbasal nerve density than FS-LASIK group (9431.0 ± 531.8, 9316.7 ± 527.8 and 8375.8 ± 552.6 µm/mm2, respectively) No significant difference in decrease in corneal subbasal nerve density between the two groups (SMILE: 5588.8 ± 618.9 µm/mm2; FS-LASIK: 5874.6 ± 567.3 µm/mm2) 6 months postoperatively |
Postoperative dry eye | |||
Denoyer et al. [32] | France | 30 subjects undergoing SMILE in both eyes (spherical correction range: −1.0 to −8.0 D; cylinder range: 0 to −1.5 D) vs. 30 age-, sex- and refraction-matched controls undergoing LASIK in both eyes | Similar rates of signs and symptoms of dryness were reported in SMILE and LASIK groups 1 month after surgery and 6 months postoperatively, incidence of dry eye symptoms in LASIK group was significantly higher than SMILE group (overall severity score 0–4: 1.2 ± 1.1 and 0.2 ± 0.4 for LASIK and SMILE, respectively) |
Gao et al. [34] | China | 15 SMILE-treated patients (preoperative MSE ± SD: −5.65 ± 1.18 D) and 32 FS-LASIK-treated patients (preoperative MSE ± SD: −5.22 ± 1.77 D) | Quicker recovery in TBUT values and OSDI scores to preoperative levels in SMILE patients (1 month) than in FS-LASIK patients (3 months) |