Laser in situ keratomyleusis (LASIK) for correction of myopia and hypermetropia: Our one year experience

Background/Aim. Laser in situ keratamileusis (LASIK) is the most commonly used refractive surgical method worldwide. The aim of this study was to examine the effectiveness and safety of LASIK in the correction of myopia and hyperopia. Methods. The study included myopic and hyperopic eyes with preoperative best corrected visual acuity (BCVA) = 1 (20/20), of the total number of 322 divided into 2 groups - 1) myopic eyes (n = 241) which were divided into 4 subgroups according to the myopia strength: a) ? -1.75 D (n = 23), b) from -2 to -3.75 D (n = 81), c) from -4 to -6.75 D (n = 113), d) ? -7 D (n = 24); 2) hyperopic eyes (n = 81) which were divided into 3 subgroups according to the hyperopia strength: a) ? +1.75D (n = 10), b) from +2 to +3.75 D (n = 46), c) ? +4 D (n = 25). Myopic and hyperopic eyes with preoperative BCVA ? 0.9 (eyes with ambliopia) were excluded from the study, as well as eyes with astigmatism > 1.5 D. To assess the effectiveness of LASIK we examined the percentage of eyes in the mentioned subgroups, which derived uncorrected visual acuity (UCVA) 6 month after the intervention to the following: a) UCVA = 1 (20/20) and b) UCVA ? 0.5 (20/40). To assess the safety of LASIK we examined the frequency of intraoperative and postoperative complications. A prospective study was performed in a 6-months follow-up period. Results. Refractive spherical equivalent (RSE) of myopic eyes was in the range from -0.75 D to -12 D. In the first subgroup preoperative mean value of RSE with standard deviation (mean RSE ? SD) was -1.39 ? 0.36 D, and 6 months after the LASIK 100% of the eyes had UCVA = 20/20. In the second subgroup preoperative mean RSE ? SD was -2.85 ? 0.50 D, and 6 months after LASIK 93% of the eyes had UCVA = 20/20, but 100% of the eyes had UCVA ? 20/40. In the third subgroup preoperative mean RSE ? SD was -5.03 ? 0.75 D, and 6 months after the LASIK 90% of the eyes had UCVA = 20/20, but 100% of the eyes had UCVA ? 20/40. In the fourth subgroup preoperative mean RSE ? SD was -7.68 ? 1.03 D, and 6 months after the LASIK 96% of the eyes had UCVA = 20/20, but 100% of eyes had UCVA ? 20/40. Refractive spherical equivalent of hyperopic eyes was in the range from +1 D to +6 D. In the first subgroup preoperative mean RSE ? SD was +1.50 ? 0.30 D, and 6 months after the LASIK 90% of the eyes had UCVA = 20/20, but 100% of the eyes had UCVA ? 20/40. In the second subgroup preoperative mean RSE ? SD was +2.65 ? 0.46 D, and 6 months after the LASIK 87% of the eyes had UCVA = 20/20, but 96% of the eyes had UCVA ? 20/40. In the third subgroup preoperative mean RSE ? SD was +4.62 ? 0.68 D, and 6 months after the LASIK 64% of the eyes had UCVA = 20/20, but 100% of the eyes had UCVA ? 20/40. In our study intraoperative complications appeared in 6 eyes (1.86%): thin flap in 2 eyes (0.62%) and epithelial defects in 4 eyes (1.24%), yet postoperative complications appeared in 10 eyes (3.10%): flap folds in 2 eyes (0.62%), epithelial ingrowth in 4 eyes (1.24%) and regression in 4 eyes (1.24%). Conclusion. LASIK is effective and safe refractive surgical method for correcting myopia up to -12 D and hyperopia up to +6 D.

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Photorefractive keratectomy for correction of myopia: Our one-year experience

Vojnosanitetski pregled ◽

10.2298/vsp1210852r ◽

2012 ◽

Vol 69 (10) ◽

pp. 852-857

Author(s):

Mirko Resan ◽

Miroslav Vukosavljevic ◽

Milorad Milivojevic

Keyword(s):

Visual Acuity ◽

Postoperative Complications ◽

Intraoperative Complications ◽

Mean Value ◽

Ablation Depth ◽

Laser In Situ Keratomileusis ◽

Photorefractive Keratectomy ◽

Corneal Tissue ◽

Surgical Method ◽

A Prospective Study

Background/Aim. Photorefractive keratectomy (PRK), after laser in situ keratomileusis (LASIK), is commonly performed refractive surgical method worldwide. The aim of this study was to examine the effectiveness and safety of PRK in correction of various strengths of myopia and to assess how much corneal tissue is being removed with one diopter sphere (Dsph) correction by using different optical zones (OZ). Methods. A prospective study with a follow-up period of 6 months included 55 patients of which 100 myopic eyes were treated by PRK method (one eye was included in 10 patients). Myopic eyes with a preoperative best corrected visual acuity (BCVA) = 1.0 (20/20) were analysed. In order to assess the effectiveness of PRK operated myopic eyes were divided into four groups according to the dioptric power: 1)? -1.75 Dsph (n = 26); 2) from -2 to -3.75 Dsph (n = 44); 3) from -4 to -6.75 Dsph (n = 23), and 4) ? -7 Dsph (n = 7). Myopic eyes with preoperative BCVA ? 0.9 (amblyopic eyes) were excluded from the study, as well as eyes with astigmatism > -1.5 Dcyl. To assess the effectiveness of PRK we examined the percentage of eyes in the mentioned groups, which derived uncorrected visual acuity (UCVA) 6 months after the intervention to the following: a) UCVA = 1.0 (20/20) and b) UCVA ? 0.5 (20/40). To assess the safety of PRK we examined the frequency of intraoperative and postoperative complications. To estimate how much corneal tissue was removed with one Dsph correction by using different OZ, we used preoperative and postoperative (after 6 months) central pachymetry values expressed in ?m and volume of cornea (central 7 mm) expressed in mm?. In that sense, we used only the myopic eyes with clear preoperative spherical refraction. The total number of these eyes was 27, of which 16 eyes were treated using a 6.5 mm OZ and 11 eyes using a 7 mm OZ. Results. Refractive spherical equivalent (RSE) for all eyes was in the range from -0.75 to -8.75 Dsph, and preoperative mean value of RSE with standard deviation (mean RSE ? SD) was -3.32 ? 1.83 Dsph. Six months after PRK, 91% of eyes had UCVA = 20/20, and 99% of eyes had UCVA ? 20/40. In the first group (? -1.75 Dsph) preoperative mean RSE ? SD was -1.34 ? 0.32 Dsph, six months after PRK, 96% of eyes had UCVA = 20/20, and 100% of eyes had UCVA ? 20/40. In the second group (from -2 to -3.75 Dsph) preoperative mean RSE ? SD was - 2.95 ? 0.57 Dsph, six months after PRK, 89% of eyes had UCVA = 20/20, and 100% of eyes had UCVA ? 20/40. In the third group (from -4 to -6.75 Dsph) preoperative mean RSE ? SD was - 4.93 ? 0.70 Dsph, six months after PRK, 100% of eyes had UCVA = 20/20. In the fourth group (? - 7 Dsph) preoperative mean RSE ? SD was -7.71 ? 0.67 Dsph, six months after PRK, 57% of eyes had UCVA = 20/20, and 86% of eyes had UCVA ? 20/40. There were no intraoperative complications while postoperative complications occurred in 2 patients - in both cases in one eye (2%). In that cases, epithelial defects were detected. In the group of eyes that were treated by 6.5 mm OZ mean RSE ? SD was -2.45 ? 0.99 Dsph, the ablation depth per 1 Dsph was 17.54 ? 5.58 ?m and ablated volume of central 7 mm cornea by 1 Dsph was 0.43 ? 0.18 mm?. In the group of eyes that were treated by 7 mm OZ mean RSE ? SD was -3.32 ? 2.26 Dsph, the ablation depth per 1 Dsph was 23.73 ? 6.91 ?m and ablated volume of central 7 mm cornea by 1 Dsph was 0.61 ? 0.31 mm?. Conclusion. PRK is effective and safe refractive surgical method for correcting myopia up to -8 .75 Dsph. OZ size is the main factor determining the depth of the excimer laser ablation of the corneal tissue volume consumed by 1 Dsph. Higher OZ value determines higher consumption of cornea tissue.

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The Effect of Astigmatism Axis on Visual Acuity

European Journal of Ophthalmology ◽

10.5301/ejo.5000890 ◽

2016 ◽

Vol 27 (3) ◽

pp. 308-311 ◽

Cited By ~ 3

Author(s):

Michael Mimouni ◽

Achia Nemet ◽

Russell Pokroy ◽

Tzahi Sela ◽

Gur Munzer ◽

...

Keyword(s):

Visual Acuity ◽

Refractive Surgery ◽

Laser In Situ Keratomileusis ◽

Stepwise Multiple Regression ◽

Spherical Equivalent ◽

Tel Aviv ◽

Uncorrected Distance Visual Acuity ◽

Laser Refractive Surgery ◽

Better Than

Purpose To evaluate the effect of astigmatism axis on uncorrected distance visual acuity (UDVA) in emmetropic eyes that underwent laser refractive surgery. Methods This retrospective study included patients who underwent laser in situ keratomileusis or photorefractive keratectomy between January 2000 and December 2015 at the Care-Vision Laser Centers, Tel Aviv, Israel. Eyes with a 3-month postoperative spherical equivalent between -0.5 D and 0.5 D were included in this study. Eyes with ocular comorbidities and planned ametropia were excluded. Study eyes were divided into 3 groups according to the steep astigmatic axis: with the rule (WTR) (60-120), oblique (31-59 or 121-149), and against the rule (ATR) (0-30 or 150-180). The UDVA of these 3 groups was compared. The oblique group was divided into oblique ATR and oblique WTR, which were compared with each other. Results A total of 17,416 consecutive eyes of 8,708 patients were studied. The WTR eyes (n = 10,651) had significantly better UDVA (logMAR 0.01 ± 0.08) than the oblique (n = 3,141, logMAR 0.02 ± 0.09) and ATR eyes (n = 3,624, logMAR 0.02 ± 0.10) (p<0.001). The oblique WTR group had significantly better UDVA than the oblique ATR group (p<0.001). The UDVA of the oblique and ATR groups was similar. Stepwise multiple regression analysis showed that the group accounted for 15% of the UDVA variance (p = 0.04). Conclusions The astigmatic axis has a small but significant effect on UDVA in emmetropic eyes; WTR was better than oblique and ATR astigmatism. Therefore, when correcting astigmatism, it may be preferable to err towards WTR astigmatism.

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EVALUATION OF THE EFFECTS OF ORTHOKERATOLOGY ON MYOPIA, ASTIGMATISM IN DA NANG FARGO ORTHO-K CENTER

Journal of Medicine and Pharmacy ◽

10.34071/jmp.2018.4.10 ◽

2018 ◽

Vol 8 (4) ◽

pp. 70-75

Author(s):

Khoi Hoang Huu

Keyword(s):

Visual Acuity ◽

Prospective Study ◽

Key Words ◽

Case Studies ◽

Outcome Evaluation ◽

Spherical Equivalent ◽

Safe Treatment ◽

Spherical Equivalent Refraction ◽

Pre Treatment ◽

A Prospective Study

Objectives: To evaluate the effects of orthokeratology (Ortho-K) on myopia, astigmatism and identify complications during applying the treatment. Methods: This is a prospective study accompanied with a series of case studies and outcome evaluation of 118 eyes of 60 patients who were diagnosed for myopia, astigmatism and were indicated wearing overnight Ortho-K lenses during the time from June 2017 to June 2018. Results: 118 eyes were prescribed wearing overnight Ortho-K lenses and their results were reported as follow: Visiual acuity ≥ 8/10 before the treatment was 1.7%, after one day of the treatment it increased to 3.4%, after 1 week it was 34.7%, after 1 month it was 71.2%, after 3 month it was 87.1% and after 6 months it accounted for 94.7%; Mean spherical equivalent refraction pre-treatment was -4.03D ± 1.70D, after 6 months of the treatment it reduced to - 0.38D ± 0.45D; Residual refraction after 6 months of the treatment ≤ 1.00D accounted for 96.5%; After 1 month of the treatment, 09 eyes (7.6%) were diagnosed for mild keratitis and 109 eyes (92.4%) had normal cornea after the treatment. Conclusions: Our results suggest that orthokeratology is a highly effective and safe treatment for correcting visual acuity in myopic and astigmatic patients. Key words: Myopia, astigmatism, orthokeratology

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Management of a Traumatic Flap Dislocation Seven Years after LASIK

Case Reports in Ophthalmological Medicine ◽

10.1155/2011/514780 ◽

2011 ◽

Vol 2011 ◽

pp. 1-3 ◽

Cited By ~ 1

Author(s):

Majid Moshirfar ◽

Erik Anderson ◽

Nathan Taylor ◽

Maylon Hsu

Keyword(s):

Visual Acuity ◽

Laser In Situ Keratomileusis ◽

Epithelial Ingrowth ◽

Blurry Vision

Seven years after uneventful laser in situ keratomileusis (LASIK), a 48-year-old woman presented one week after being hit with an iron cord with blurry vision, pain, and irritation. The injury resulted in traumatic flap dislocation, epithelial ingrowth, and macrostriae. Following epithelial removal, the flap was refloated and repositioned. Nine interrupted sutures were used to secure the flap. Three-weeks after surgery with no sutures remaining, the epithelial ingrowth and macrostriae had resolved with a visual acuity of 20/20.

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Tracheal Squamous Cell Carcinoma Treated with Tracheal Resection and Anastomosis in a Cat

Case Reports in Veterinary Medicine ◽

10.1155/2020/8818660 ◽

2020 ◽

Vol 2020 ◽

pp. 1-8

Author(s):

Zachary A. Miller ◽

Sheldon Padgett ◽

Alex Terreros ◽

Emily Pearce

Keyword(s):

Squamous Cell Carcinoma ◽

Radiation Therapy ◽

Postoperative Complications ◽

Cell Carcinoma ◽

Squamous Cell ◽

Intraoperative Complications ◽

Tracheal Resection ◽

First Report ◽

The Third ◽

Resection And Anastomosis

A 10-year-old male castrated domestic shorthair cat presented for a suspected tracheal mass. Radiographs confirmed an intraluminal tracheal mass. Tracheal resection and anastomosis of 5 tracheal rings was performed with minimal, mild intraoperative complications and no postoperative complications. Histopathology of the tracheal mass revealed a diagnosis of squamous cell carcinoma (SCC) with incomplete margins both cranially and caudally. Further treatment, including surgical revision, radiation therapy, or chemotherapy, was recommended. At the time of publication, no further treatment has been initiated, and a scheduled consultation with the oncologist has been canceled. The cat is doing well at home with no reported signs of recurrence 120 days postoperatively. This is the first report of a cat with a tracheal SCC to be treated with a tracheal resection and anastomosis and only the third feline tracheal SCC to be treated in the veterinary literature.

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Prophylactic Corneal Cross-Linking in Myopic Femtosecond Laser-Assisted In Situ Keratomileusis: Long-Term Visual and Refractive Outcomes

Optics ◽

10.3390/opt2010006 ◽

2021 ◽

Vol 2 (1) ◽

pp. 55-62

Author(s):

Federico Alonso-Aliste ◽

Jonatan Amián-Cordero ◽

Rahul Rachwani-Anil ◽

Concepción De-Hita-Cantalejo ◽

Davide Borroni ◽

...

Keyword(s):

Visual Acuity ◽

Femtosecond Laser ◽

Excimer Laser ◽

Cross Linking ◽

Spherical Equivalent ◽

Refractive Outcomes ◽

Safety Effectiveness

The purpose of our study was to evaluate the safety, effectiveness, predictability, and stability of myopic and astigmatic laser-assisted in situ keratomileusis (LASIK) with simultaneous prophylactic corneal cross-linking (CXL) in thin corneas. In total, 100 eyes from 50 patients who were subjected to myopic and astigmatism femtosecond LASIK with simultaneous prophylactic CXL were included. The design of the study was retrospective, longitudinal, and observational. All patients had a 48-month follow-up. The MEL 80 excimer laser was utilized with the Aberration Smart Ablation platform. CXL treatment was applied when the predicted stromal thickness was less than 330 µm. Patients’ mean age was 30.22 ± 5.97 years. Previous mean spherical equivalent was −5.50 ± 1.65 (−9.50 to −1.13) diopters (D). Postoperative mean spherical equivalent was −0.24 ± 0.29 (−0.85 to +0.50) D. Visual acuity (VA) of 20/20 or better was observed in 87% of the eyes and no eyes experienced VA loss. Spherical equivalent within ±0.50 D was observed in 93% of eyes, and 4% of eyes varied by 0.50 D or more between 3 and 48 months. Prophylactic corneal cross-linking with simultaneous femtosecond laser-assisted in situ keratomileusis in thin corneas proved to be effective, safe, and predictable. The results remained stable after 48 months of follow-up.

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Effect of Photorefractive Keratectomy and Laser in situ Keratomileusis in High Myopia on logMAR Visual Acuity and Contrast Sensitivity

Acta Medica (Hradec Kralove Czech Republic) ◽

10.14712/18059694.2019.3 ◽

2003 ◽

Vol 46 (1) ◽

pp. 15-18 ◽

Cited By ~ 1

Author(s):

Hana Langrová ◽

Matthias Derse ◽

Dagmar Hejcmanová ◽

Alena Feuermannová ◽

Pavel Rozsíval ◽

...

Keyword(s):

Visual Acuity ◽

Contrast Sensitivity ◽

High Myopia ◽

Laser In Situ Keratomileusis ◽

Photorefractive Keratectomy ◽

Spherical Equivalent ◽

Spatial Frequencies ◽

Quality Of Vision

Purpose: To compare effect of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) on contrast sensitivity (CS) and best corrected visual acuity (BCVA) in high myopia. Methods: 38 myopes (PRK) and 31 patients (LASIK) were examined before and 1, 3, 6, and 12 months postoperatively. Mean preoperative spherical equivalent was -8.0 ± 1.7D (PRK) and -9.2 ± 2.1D (LASIK). CS was tested on a computerized system of the Contrast Sensitivity 8010 Type at 6 spatial frequencies (0.74 and 29.55 c/deg), BCVA was measured on logMAR charts. Results: At 12 months postoperatively, mean spherical equivalent was -0.6 ± 1.0D (PRK) and -1.0 ± 0.8D (LASIK). Postoperative values of CS were significantly higher in the PRK group, except for spatial frequencies of 3.69 and 7.39 c/deg up to 3 months postoperatively. The initial significant decrease of BCVA lasted up to 6 months after PRK. In the LASIK group BCVA was not significantly different from its preoperative level at the 3-months follow-up. Conclusions: The significant improvement of CS after PRK suggest that PRK can improve quality of vision in eyes with high myopia. Although recovery of BCVA after LASIK was faster than after PRK, there may be a persistent decrease in CS.

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Femtosecond Laser-Assisted In Situ Keratomileusis Treatment of Residual Refractive Error following Femtosecond Laser-Enabled Keratoplasty

Journal of Ophthalmology ◽

10.1155/2019/8520183 ◽

2019 ◽

Vol 2019 ◽

pp. 1-6

Author(s):

Elizabeth Shen ◽

Lester Tsai ◽

Hannah Muniz Castro ◽

Matthew Wade ◽

Marjan Farid

Keyword(s):

Visual Acuity ◽

Femtosecond Laser ◽

Spherical Equivalent ◽

Case Review ◽

Retrospective Case ◽

Distance Visual Acuity ◽

Uncorrected Distance Visual Acuity ◽

Corrected Distance Visual Acuity ◽

The University

Purpose. To evaluate the safety and effectiveness of femtosecond laser-assisted in situ keratomileusis (LASIK) in the treatment of residual myopia and astigmatism following femtosecond laser-enabled keratoplasty (FLEK). Design. Retrospective case review. Methods. Chart review of all patients with prior FLEK who subsequently underwent femto-LASIK surgery after full suture removal was performed at the Gavin Herbert Eye Institute at the University of California, Irvine. A total of 14 eyes in 13 patients met this criterion, and their comprehensive examinations performed at standard intervals were reviewed. Main outcome measures include uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) expressed as the logarithm of the minimum angle of resolution (logMAR), manifest refractive astigmatism, and spherical equivalent. Results. From the preoperative visit to the 3 month visit, all 14 eyes significantly improved in UDVA (logMAR, 0.93 ± 0.23 to 0.44 ± 0.32, P=0.002) with no loss of CDVA (logMAR, 0.26 ± 0.19 to 0.18 ± 0.23, P=0.50). All 14 eyes showed significant improvement in manifest refractive astigmatism (4.71 ± 1.77 to 2.18 ± 1.45 diopters (D), P=0.003) and spherical equivalent (−2.57 ± 2.45 to −0.48 ± 0.83 D, P=0.0007). There were no flap or graft complications as a result of femto-LASIK. Conclusions. Our findings suggest that femto-LASIK on eyes with prior FLEK is safe and effective in improving visual acuity and reducing residual astigmatism.

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Optical and visual quality comparison of implantable collamer lens and femtosecond laser assisted laser in situ keratomileusis for high myopia correction

International Journal of Ophthalmology ◽

10.18240/ijo.2021.05.15 ◽

2021 ◽

Vol 14 (5) ◽

pp. 737-743

Author(s):

Zheng Jiang ◽

◽

Dong-Qiang Luo ◽

Jiao Chen ◽

◽

...

Keyword(s):

Visual Acuity ◽

Femtosecond Laser ◽

Clinical Outcomes ◽

High Myopia ◽

Cutoff Frequency ◽

Laser In Situ Keratomileusis ◽

Spherical Equivalent ◽

Implantable Collamer Lens ◽

Significant Difference

AIM: To compare clinical outcomes and refractive stability of implantable collamer lens (ICL) implantation and femtosecond laser assisted laser in situ keratomileusis (FS-LASIK) for high myopia correction. METHODS: The Optical Quality Analysis System (OQAS) was used to evaluate clinical outcomes objectively after operation for high myopia correction. We compared the two procedures in terms of 1-year changes in uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), safety index, efficacy index, spherical equivalent, modulation transfer function (MTF) cutoff frequency, strehl ratio (SR) and objective scatter index (OSI). RESULTS: At 1y postoperatively, the safety indices were 1.33±0.27 in ICL group, and 1.17±0.24 in FS-LASIK group. 39.58% in the ICL group and 27.59% in the FS-LASIK group gained CDVA in 2 lines or better than that in preoperative CDVA. The efficacy indices were 1.28±0.22 in ICL group, and 1.13±0.26 in FS-LASIK group. The changes of spherical equivalent from 1wk to 1y postoperatively was -0.12±0.37 D in ICL group, and -0.79±0.58 D in FS-LASIK group (P<0.05). Spherical equivalent within ±0.50 D was achieved in 97.92% in ICL group and 68.97% in FS-LASIK group. MTF cutoff frequency were higher with ICL as compared to FS-LASIK (P<0.05) at each postoperative follow-up stage; for postoperative 1mo later, SR was statistically significant difference between two groups (P<0.05); with no statistically significant difference in OSI between two groups (P>0.05) in postoperative 3mo later. CONCLUSION: ICL implantation and FS-LASIK procedures both provide good safety and predictability in high myopia correction. ICL implantation provides better clinical outcomes and refractive stability than FS-LASIK.

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Visual differences in topography-guided versus wavefront-optimized LASIK in the treatment of myopia: a Meta-analysis

International Journal of Ophthalmology ◽

10.18240/ijo.2021.10.19 ◽

2021 ◽

Vol 14 (10) ◽

pp. 1602-1609

Author(s):

Peng-Cheng Hu ◽

◽

Xian-Hui Wu ◽

Yan-Qing Li ◽

Ke-Wei Li ◽

...

Keyword(s):

Visual Acuity ◽

Web Of Science ◽

Spherical Aberration ◽

Meta Analysis ◽

Laser In Situ Keratomileusis ◽

Wavefront Aberration ◽

Spherical Equivalent ◽

Uncorrected Distance Visual Acuity ◽

Manifest Refraction

AIM: To investigate the potential differences between topography-guided (TG) and wavefront-optimized (WFO) laser in situ keratomileusis (LASIK) for the treatment of myopia. METHODS: A systematic literature search was performed to determine relevant trials comparing LASIK with TG and WFO from the time of library construction to August 2020, and The PubMed, Cochrane, Web of Science, EMBASE and Chinese databases (i.e. CNKI, CBM, WAN FANG and VIP) were accessed. The data on visual acuity, refractive status and wavefront aberration were retrieved and evaluated from three to six months after surgery. STATA (version 14.0) software was used for statistical analysis. A cumulative Meta-analysis was simultaneously performed. RESULTS: Eleven studies with a total of 1425 eyes were incorporated. No statistically significant differences were evident between TG and WFO ablation in the proportion of eyes achieving an uncorrected distance visual acuity (UCVA) of 20/20 or better (P=0.377), gaining one line or more (P=0.05), postoperative cylinder (P=0.40), vertical coma (P=0.593) and horizontal coma (P=0.957). After TG ablation, the proportion of the patients’ eyes of which postoperative refraction is within ±0.5 diopter of the target refraction was significantly higher than that undergoes WFO (P=0.003). As opposed to the WFO group, manifest refraction spherical equivalent (MRSE; P=0.000) was lower, and UCVA (P=0.005) was better in the TG group. The higher-order aberrations (HOAs; P=0.000), spherical aberration (P=0.000) and coma (P=0.000) were significantly lower in TG group. The cumulative Meta-analysis illustrated that the proportion of eyes achieving UCVA of 20/20 or better, postoperative refraction within ±0.5 diopter, and MRSE has steady between the two groups. CONCLUSION: Both TG-LASIK and WFO-LASIK are safe, effective, and predictable for correcting myopia. TG-LASIK may produce fewer aberration and is more precise than WFO-LASIK.

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