Prophylactic corneal crosslinking in myopic small-incision lenticule extraction - Long-term visual and refractive outcomes

Abstract Background To compare postoperative clinical outcomes of high myopia after being treated by Small incision lenticule extraction (SMILE) and femtosecond laser in situ keratomileusis (FS-LASIK).Methods Comprehensive studies were conducted on the PubMed, MEDLINE, EMBASE, the Cochrane Library, and Chinese databases.Trials meeting the selection criteria were quality appraised, and the data were extracted by 2 independent authors, and the RevMan 5.3 version software were used in analyzing.Result Ten studies involving 637 patients (1093 eyes;575 eyes in the SMILE group and 518 eyes in the FS-LASIK group) were included in this meta-analysis. Pooled result revealed no significant differences in the following outcomes: the logMAR values of postoperative UDVA(WMD = -0.01, 95% CI: -0.02,0.00, I²=0%, P = 0.10 at postoperative 1mo; WMD =-0.01, 95% CI: -0.00 to 0.01, I²=0%,P = 0.35 at postoperative 3mo; WMD = -0.01, 95% CI:-0.02 to 0.01, I²=17%,P = 0.26 at long term), the logMAR values of postoperative CDVA(WMD = -0.02, 95% CI, -0.04 to 0.00, I²=0%, P = 0.11),and the postoperative mean refractive SE (WMD =0.02, 95% CI:0.04 to 0.08, I²=29%, P=0.60) . In the long-term observation, postoperative tHOA (WMD =-0.10, 95% CI:-0.13 to -0.07, I²=15%, P<0.00001)and postoperative spherical aberration (WMD =-0.13, 95% CI:--0.17 to -0.09, I²=38%, P<0.00001) were found to be less in the SMILE group compared with the FS-LASIK group, but no significant difference was found in postoperative coma (WMD =-0.02, 95% CI:-0.04 to 0.00, I²=98%, P=0.40).We also found greater PCE change post FS-LASIK than SMILE at long term follow-ups(WMD =-0.69, 95% CI:-1.36 to -0.01, I²=0%, P<0.05, however, there was no significant difference between the two groups at 3- or 6- months.(WMD =-0.19, 95% CI:-0.41 to 0.03, I²=31%, P=0.09;WMD =-0.20, 95% CI:-0.50 to 0.10, I²=17%, P=0.20)Conclusion For patients with high myopia, both SMILE and FS-LASIK are safe and efficacious. However, SMILE induced less tHOA and spherical aberration compared with FS-LASIK. Besides, FS-LASIK showed a greater increase in PCE than SMILE only at long term follow-ups. It remains to be seen whether the patients can get a better visual quality after SMILE and more comparative studies focused on high myopia is necessary.

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Long-term Visual Quality after Small Incision Lenticule Extraction (SMILE) and Laser Epithelial Keratomileusis (LASEK) for Low Myopia

10.21203/rs.3.rs-640151/v1 ◽

2021 ◽

Author(s):

Mengjun Fu ◽

Meiyan Li ◽

Ruoyan Wei ◽

Chuanwei Zhang ◽

Yangyi Huang ◽

...

Keyword(s):

Spherical Aberration ◽

Visual Quality ◽

Small Incision Lenticule Extraction ◽

Wavefront Aberrations ◽

Small Incision ◽

Patient Reported ◽

Manifest Refraction ◽

Lenticule Extraction ◽

Efficacy Index

Abstract Background: Few studies have reported the visual outcomes of small-incision lenticule extraction (SMILE) and laser-assisted epithelial keratomileusis (LASEK) for myopia correction. This study aims to compare the visual quality and corneal wavefront aberrations after SMILE and LASEK for low-myopia correction.Methods: In this prospective study, we included 29 eyes of 29 patients who received SMILE, and 23 eyes of 23 patients who received LASEK between June 2018 and January 2019. The following measurements were assessed: uncorrected (UDVA) and corrected (CDVA) distance visual acuity, manifest refraction, corneal wavefront aberrations, and subjective visual quality. All patients were followed up for two years.Results: All procedures were uneventful. An efficacy index of 1.19 ± 0.17 was established in the SMILE group and 1.23 ± 0.20 in the LASEK group. No eyes lost more than two lines of CDVA. We found that 93% (27/29) of the treated eyes in the SMILE group and 91% (21/23) in the LASEK group had spherical equivalent (SE) within ± 0.25D. The increases in the total corneal spherical aberration and the corneal front spherical aberration were lower in the SMILE group than in the LASEK group (P < 0.01). In contrast, the increases in the total corneal vertical coma and the corneal front vertical coma in the SMILE group were greater than those in the LASEK group (P < 0.01).Conclusion: Both SMILE and LASEK have good safety, stability, and patient-reported satisfaction for low myopia. SMILE induced less corneal spherical aberration but greater vertical coma than LASEK.

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Influence of age on small incision lenticule extraction outcomes

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2020-316865 ◽

2020 ◽

pp. bjophthalmol-2020-316865

Author(s):

Laura Primavera ◽

Mario Canto-Cerdan ◽

Jorge L Alio ◽

Jorge L Alio del Barrio

Keyword(s):

Corneal Stroma ◽

Study Groups ◽

Visual Response ◽

Small Incision Lenticule Extraction ◽

Small Incision ◽

Refractive Outcomes ◽

Significant Difference ◽

Lenticule Extraction ◽

The Mean ◽

Over 40 Years

PurposeTo evaluate the influence of patient’s age at the time of surgery on small incision lenticule extraction (SMILE) refractive outcomes.MethodsThis is a retrospective, consecutive, comparative study. We compared the refractive outcomes after myopic SMILE from two groups of patients divided by age (patients ≤35 and ≥40 years old). All eyes were evaluated preoperatively and at 1 and 6 months postoperatively. Main outcome measures were differences on efficacy, safety, predictability and astigmatic changes by vector analysis with ASSORT software between both study groups.Results102 matched eyes of 53 patients were included. Preoperatively, we evidenced no differences in the mean SE or astigmatism between groups. However, 6 months postoperatively we observed a significantly worse mean astigmatism (p=0.019), while not regarding SE, in the older population, with a trend towards undercorrection of the refractive cylinder in the ≥40 group. We also observed a statistically significant difference in the efficacy (0.86–1 month and 0.97–6 months in ≥40group vs 0.97–1 month and 1.07–6 months in the ≤35 group; p=0.003) and safety indexes (0.93–1 month and 1.04–6 months in ≥40 group vs 1.0–1 month and 1.11–6 months in the ≤35 group; p=0.008) at 6 months among groups.ConclusionsPost-SMILE refractive outcomes in those patients over 40 years of age, although acceptable, are not as good as those obtained in younger patients, showing a significantly lower efficacy and safety indexes, and poorer astigmatic outcomes, with a tendency towards undercorrection. We hypothetise that the increased corneal stroma stiffness in the aged group modifies the post-SMILE corneal stroma remodelling capacity, thus affecting the SMILE refractive and visual response.

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Small incision lenticule extraction for the correction of high myopia

European Journal of Ophthalmology ◽

10.1177/1120672119861481 ◽

2019 ◽

Vol 30 (5) ◽

pp. 917-927

Author(s):

Suphi Taneri ◽

Saskia Kießler ◽

Anika Rost ◽

Tim Schultz ◽

H Burkhard Dick

Keyword(s):

Visual Acuity ◽

High Myopia ◽

Case Series ◽

Small Incision Lenticule Extraction ◽

Distance Visual Acuity ◽

Small Incision ◽

Refractive Outcomes ◽

Uncorrected Distance Visual Acuity ◽

Corrected Distance Visual Acuity ◽

Lenticule Extraction

Purpose: Excimer laser-based refractive procedures can have less predictable results when used for correcting high myopia than when used for moderate myopia. Small incision lenticule extraction might overcome this weakness. However, small incision lenticule extraction is only Food and Drug Administration approved for use in myopic eyes up to −8 D with astigmatism of −3 D or less. We report outcomes of small incision lenticule extraction in highly and moderately myopic eyes and compare these to modern laser-assisted in situ keratomileusis. Methods: Retrospective, observational consecutive case series. Inclusion criteria: attempted myopic spherical correction ⩾−8 or−3 to −7.75 D with astigmatism ⩽−3 D, and corrected distance visual acuity of 1.0 (decimal scale) or better. Results: A total of 62 highly myopic and 407 moderately myopic eyes were included. At 3 months postoperatively, the highly myopic eyes had a mean spherical equivalent refraction of −0.28 ± 0.41 D (range: −1.13 to +0.75 D). Mean uncorrected distance visual acuity was 1.0. Mean efficacy index was 0.84. Mean safety index was 1.03. Uncorrected distance visual acuity same or better than corrected distance visual acuity: 61%. Astigmatism was ⩽0.5 D in 90% and ⩽1 D in 100%. The results in the moderately myopic eyes were comparable. Conclusion: We found equally good visual and refractive outcomes after small incision lenticule extraction for the correction of high and of moderate myopia combined with an astigmatic correction of up to 3 D, respectively.

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Visual and Refractive Outcomes of Photorefractive Keratectomy and Small Incision Lenticule Extraction (SMILE) for Myopia

Journal of Refractive Surgery ◽

10.3928/1081597x-20160602-02 ◽

2016 ◽

Vol 32 (9) ◽

pp. 604-610 ◽

Cited By ~ 10

Author(s):

Yusuf Yildirim ◽

Onur Olcucu ◽

Cengiz Alagoz ◽

Abdurrahman Basci ◽

Alper Agca ◽

...

Keyword(s):

Photorefractive Keratectomy ◽

Small Incision Lenticule Extraction ◽

Small Incision ◽

Refractive Outcomes ◽

Lenticule Extraction

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Visual and Refractive Outcomes of Small-Incision Lenticule Extraction in High Myopia: 5-Year Results

Journal of Ophthalmology ◽

10.1155/2018/5893126 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6 ◽

Cited By ~ 7

Author(s):

Alper Ağca ◽

İhsan Çakır ◽

Beril Tülü Aygün ◽

Dilek Yaşa ◽

Yusuf Yıldırım ◽

...

Keyword(s):

Visual Acuity ◽

High Myopia ◽

Spherical Equivalent ◽

Small Incision Lenticule Extraction ◽

Distance Visual Acuity ◽

Small Incision ◽

Refractive Outcomes ◽

Lenticule Extraction ◽

The Mean

Purpose. To report long-term visual and refractive results of small-incision lenticule extraction (SMILE) in treatment of high myopia. Materials and Methods. Medical records of patients who underwent SMILE for surgical correction of myopia or myopic astigmatism were retrospectively reviewed. Only patients with a preoperative spherical equivalent of subjective manifest refraction (SE) ≥ 6 D and a postoperative follow-up of 5 years were included in the study. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and SE were analyzed preoperatively and at 1-, 3-, and 5-year postoperative periods. Results. Thirty-seven eyes of 37 patients were included in the study. The mean attempted SE was −7.47 ± 1.10 D (range −6.00 to −10.00 D). At the 5-year visit, the mean difference between achieved and attempted SE was −0.43 ± 0.47 (0.50 to −1.25 D). Mean postoperative UDVA and CDVA were 0.20 ± 0.18 and 0.06 ± 0.08 logMAR, respectively. At the 1-year visit, 70% and 97% of the eyes were within ±0.50 D and ±1.00 D of the intended correction. At the 5-year follow-up, 59% and 92% percent of the eyes were within ±0.50 D and ±1.00 D of the intended SE, respectively. At the 5-year visit, the efficacy index was 0.89 ± 0.26 and the safety index was 1.16 ± 0.20. Fifty-four percent of the eyes gained one or more lines of CDVA. Conclusion. SMILE with an intended correction of up to a spherical equivalent of 10 D is safe and effective. However, there is regression of the refractive effect over extended follow-up.

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Two-year observation of posterior corneal elevations after small incision lenticule extraction (SMILE) for myopia higher than −10 dioptres

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2018-313498 ◽

2019 ◽

Vol 104 (1) ◽

pp. 142-148 ◽

Cited By ~ 5

Author(s):

Xueyi Zhou ◽

Jianmin Shang ◽

Bing Qin ◽

Yu Zhao ◽

Xingtao Zhou

Keyword(s):

Central Area ◽

Control Group ◽

Small Incision Lenticule Extraction ◽

Small Incision ◽

Long Term Follow Up ◽

Lenticule Extraction ◽

Measured Change

AimTo investigate the change in posterior corneal elevations (PCEs) of eyes with extremely high myopia 2 years after small incision lenticule extraction (SMILE).MethodsWe evaluated 39 eyes of 39 patients with spherical equivalent higher than −10.00 dioptres (D). Using a Scheimpflug camera (Pentacam), we measured change in PCEs at 1 day, 3 months, 6 months and 2 years after SMILE. Another 34 eyes of 34 patients who underwent femtosecond laser-assisted in situ keratomileusis (FS-LASIK) were examined before, at 1 day and long-term after surgery as the control group. For each eye, elevations at central, thinnest, maximal points and 24 other predetermined points were measured.ResultsNo significant forward displacements of PCEs were observed in both surgeries. The maximal but not significant forward displacement occurred around 3–6 months following SMILE, and all returned to original levels 6 months postoperatively except superior area. The peripheral area tended to displace backward, while the central area tended forwardly. In both procedures, elevations along horizontal meridians, inferior and temporal hemispheres were significantly higher than those along vertical meridians, superior and nasal hemispheres, respectively (p<0.05). Elevation on the 4 mm, 6 mm diameters at 1 day and on the 6 mm diameter and temporal hemisphere at long-term follow-up postoperatively were significantly higher in FS-LASIK than SMILE (p<0.05). Change in elevations on the 6 mm diameter circle correlated with residual bed thickness (p=0.047).ConclusionsSMILE is a safe way to correct for myopia higher than −10 D, with PCEs remaining stable 2 years after surgery.

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Clinical outcomes after small-incision lenticule extraction versus femtosecond laser-assisted LASIK for high myopia: A meta-analysis

PLoS ONE ◽

10.1371/journal.pone.0242059 ◽

2021 ◽

Vol 16 (2) ◽

pp. e0242059

Author(s):

Yanyan Fu ◽

Yewei Yin ◽

Xiaoying Wu ◽

Yuanjun Li ◽

Aiqun Xiang ◽

...

Keyword(s):

Visual Acuity ◽

Femtosecond Laser ◽

Clinical Outcomes ◽

High Myopia ◽

Meta Analysis ◽

Small Incision Lenticule Extraction ◽

Distance Visual Acuity ◽

Small Incision ◽

Lenticule Extraction

Aim To compare postoperative clinical outcomes of high myopia after small-incision lenticule extraction (SMILE) and femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK). Methods From March 2018 to July 2020, PubMed, MEDLINE, Embase, the Cochrane Library, and several Chinese databases were comprehensively searched. The studies meeting the criteria were selected and included; the data were extracted by 2 independent authors. The clinical outcome parameters were analyzed with RevMan 5.3. Results This meta-analysis included twelve studies involving 766 patients (1400 eyes: 748 receiving SMILE and 652 receiving FS-LASIK). Pooled results revealed no significant differences in the following outcomes: the logarithm of the mean angle of resolution (logMAR) of postoperative uncorrected distance visual acuity (weighted mean difference (WMD) = -0.01, 95% confidence interval (CI): -0.02 to 0.00, I2 = 0%, P = 0.07 at 1 mo; WMD = -0.00, 95% CI: -0.01 to 0.01, I2 = 0%, P = 0.83 at 3 mo; WMD = -0.00, 95% CI: -0.01 to 0.00, I2 = 32%, P = 0.33 in the long term), and the postoperative mean refractive spherical equivalent (WMD = -0.03, 95% CI: -0.09 to 0.03, I2 = 13%, P = 0.30). However, the SMILE group had significantly better postoperative corrected distance visual acuity (CDVA) than the FS-LASIK group (WMD = -0.04, 95% CI, -0.05 to -0.02, I2 = 0%, P<0.00001). In the long term, postoperative total higher-order aberration (WMD = -0.09, 95% CI: -0.10 to -0.07, I2 = 7%, P<0.00001) and postoperative spherical aberration (WMD = -0.15, 95% CI: -0.19 to -0.11, I2 = 29%, P<0.00001) were lower in the SMILE group than in the FS-LASIK group; a significant difference was also found in postoperative coma (WMD = -0.05, 95% CI: -0.06 to -0.03, I2 = 30%, P<0.00001). Conclusion For patients with high myopia, both SMILE and FS-LASIK are safe, efficacious and predictable. However, the SMILE group demonstrated advantages over the FS-LASIK group in terms of postoperative CDVA, while SMILE induced less aberration than FS-LASIK. It remains to be seen whether SMILE can provide better visual quality than FS-LASIK; further comparative studies focused on high myopia are necessary.

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