Corneal curvature, asphericity, and aberrations after transepithelial photorefractive keratectomy and femtosecond laser-assisted in situ keratomileusis for myopia: A prospective comparative study

Abstract Purpose To investigate the predictive factors of postoperative myopic regression among subjects who have undergone laser-assisted subepithelial keratomileusis (LASEK), laser-assisted in situ keratomileusis (LASIK) flap created with a mechanical microkeratome (MM), and LASIK flap created with a femtosecond laser (FS). All recruited patients had a manifest spherical equivalence (SE) from − 6.0D to − 10.0D myopia. Methods This retrospective, observational case series study analyzed outcomes of refraction at 1 day, 1 week, and 1, 3, 6, and 12 months postoperatively. Predictors affecting myopic regression and other covariates were estimated with the Cox proportional hazards model for the three types of surgeries. Results The study enrolled 496 eyes in the LASEK group, 1054 eyes in the FS-LASIK group, and 910 eyes in the MM-LASIK group. At 12 months, from − 6.0D to − 10.0D myopia showed that the survival rates (no myopic regression) were 52.19%, 59.12%, and 58.79% in the MM-LASIK, FS-LASIK, and LASEK groups, respectively. Risk factors for myopic regression included thicker postoperative central corneal thickness (P ≦ 0.01), older age (P ≦ 0.01), aspherical ablation (P = 0.02), and larger transitional zone (TZ) (P = 0.03). Steeper corneal curvature (Kmax) (P = 0.01), thicker preoperative central corneal thickness (P < 0.01), smaller preoperative myopia (P < 0.01), longer duration of myopia (P = 0.02), with contact lens (P < 0.01), and larger optical zone (OZ) (P = 0.02) were protective factors. Among the three groups, the MM-LASIK had the highest risk of postoperative myopic regression (P < 0.01). Conclusions The MM-LASIK group experienced the highest myopic regression, followed by the FS-LASIK and LASEK groups. Older age, aspheric ablation used, thicker postoperative central corneal thickness, and enlarging TZ contribute to myopic regression; steeper preoperative corneal curvature (Kmax), longer duration of myopia, with contact lens, thicker preoperative central corneal thickness, lower manifest refraction SE, and enlarging OZ prevent postoperative myopic regression in myopia from − 6.0D to − 10.0D.

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Whole Globe Enucleation Versus In Situ Excision for Donor Corneal Retrieval-A Prospective Comparative Study

Cornea ◽

10.1097/ico.0b013e31817f812e ◽

2008 ◽

Vol 27 (10) ◽

pp. 1103-1108 ◽

Cited By ~ 12

Author(s):

Vishal Jhanji ◽

Radhika Tandon ◽

Namrata Sharma ◽

Jeewan S Titiyal ◽

Gita Satpathy ◽

...

Keyword(s):

Comparative Study ◽

Prospective Comparative Study

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A Comparative Study of Laser In Situ Keratomileusis Flaps Created Using Single-Functional Versus Multifunctional Femtosecond Laser for Refractive Surgery

Cornea ◽

10.1097/ico.0000000000002353 ◽

2020 ◽

Vol 39 (9) ◽

pp. 1122-1131

Author(s):

Marcello N. Colombo-Barboza ◽

Luiz R. Colombo-Barboza ◽

Maria Margarida N. Colombo-Barboza ◽

Guilherme N. Colombo-Barboza

Keyword(s):

Femtosecond Laser ◽

Comparative Study ◽

Refractive Surgery ◽

Laser In Situ Keratomileusis ◽

Functional Versus

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The surgery correction of presbyopia: the modern possibilities

Medical Journal of the Russian Federation ◽

10.18821/0869-2106-2016-22-3-146-152 ◽

2016 ◽

Vol 22 (3) ◽

pp. 146-152

Author(s):

Kirill B. Pershin

Keyword(s):

Laser Ablation ◽

Femtosecond Laser ◽

Radio Frequency ◽

Surgical Correction ◽

Intraocular Lenses ◽

Photorefractive Keratectomy ◽

Social Significance ◽

Advantages And Disadvantages ◽

Optical Zone

The article presents review of actual publications' data concerning surgical correction of presbyopia. The data is presented related to social significance of presbyopia alongside with other disorders of refraction. The techniques applying monovision include thermokeratoplasty and such its modification as laser and radio-frequency thermokeratoplasty. All of them have number of deficiencies. The exdmer-laser ablation of cornea in the form of Laser-Assisted in Situ Keratomileusis (LASIK) or Photorefractive keratectomy (PRK) are considered as kerato-refractional techniques of correction of presbyopia. The femtosecond laser intrastromal correction of presbyopia (INTRACOR) is also labeled as kerato-refractional technique of correction of presbyopia and it is based on making intrastromal concentric rings in the central optical zone of cornea. The deficiency of INTRACOR is a relatively high cost of procedure due to application of femtosecond laser. The implantation of inlays (artificial devices) into cornea permits correcting presbyopia with less financial expenses. However, there are number of contraindications for implementing. The Tornton and Schachar operations are referred to the group of sclerotic operations of correcting presbyopia. However, nowadays these interventions are practically out of application. The implantation of intraocular lenses, including accommodating, multi-focal and monofocal by the principle of monovision ones, can be considered as the most adequate mode of correction of presbyopia. The advantages and disadvantages of implantation of various types of intraocular lenses are considered in detail.

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Measurement of corneal curvature change after mechanical laser in situ keratomileusis flap creation and femtosecond laser flap creation

Journal of Cataract & Refractive Surgery ◽

10.1016/j.jcrs.2007.09.023 ◽

2008 ◽

Vol 34 (2) ◽

pp. 238-242 ◽

Cited By ~ 23

Author(s):

Dolores Ortiz ◽

Jorge L. Alió ◽

David Piñero

Keyword(s):

Femtosecond Laser ◽

Laser In Situ Keratomileusis ◽

Corneal Curvature ◽

Flap Creation

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Effect of Transepithelial Photorefractive Keratectomy without Mitomycin C in the Treatment of Femtosecond Laser In Situ Keratomileusis Corneal Flap Complications

Journal of Ophthalmology ◽

10.1155/2021/8847922 ◽

2021 ◽

Vol 2021 ◽

pp. 1-7

Author(s):

Jing Wang ◽

Weiqian Cao ◽

Liming Tao

Keyword(s):

Visual Acuity ◽

Femtosecond Laser ◽

Mitomycin C ◽

Laser In Situ Keratomileusis ◽

Photorefractive Keratectomy ◽

Distance Visual Acuity ◽

Uncorrected Distance Visual Acuity ◽

Haze Formation

Purpose. To assess the efficacy and safety of transepithelial photorefractive keratectomy (TPRK) without mitomycin C as treatment for femtosecond laser in situ keratomileusis (FS-LASIK) corneal flap complications. Methods. Eight patients with corneal flap complications that occurred after FS-LASIK (five with eccentric flaps, two with buttonhole flaps, and one with a thick flap) were included in the study. Patients were treated with TPRK without mitomycin C between two weeks and twelve months after surgery. The postoperative manifest refraction, uncorrected distance visual acuity, and haze formation were assessed during six months of follow-up. Results. The mean manifest refractive spherical and cylinder refraction was 0.16 ± 0.26 and −0.44 ± 0.33 diopters, respectively, at six months postoperatively. The uncorrected distance visual acuity was above 20/25 in all patients after six months of follow-up. No haze formation was detected. Conclusions. TPRK without mitomycin C appears to be a safe and effective treatment for FS-LASIK corneal flap complications.

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Changes in Intraocular Pressure after Transepithelial Photorefractive Keratectomy and Femtosecond Laser In Situ Keratomileusis

Journal of Ophthalmology ◽

10.1155/2021/5592195 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Chien-Chih Chou ◽

Po-Jen Shih ◽

Hung-Chou Lin ◽

Jun-Peng Chen ◽

Jia-Yush Yen ◽

...

Keyword(s):

Intraocular Pressure ◽

Femtosecond Laser ◽

Young’S Modulus ◽

Young's Modulus ◽

Laser In Situ Keratomileusis ◽

Photorefractive Keratectomy ◽

Linear Regression Models ◽

Postoperative Changes

Purpose. To investigate the changes in intraocular pressure (IOP) and biomechanically corrected IOP (bIOP) in patients undergoing transepithelial photorefractive keratectomy (TPRK) and femtosecond laser in situ keratomileusis (FS-LASIK) and to determine the effects of preoperative biomechanical factors on IOP and bIOP changes after FS-LASIK and TPRK. Design. A retrospective comparative study. Methods. We retrospectively investigated the IOP and corneal biomechanical changes in 93 eyes undergoing FS-LASIK and 104 eyes undergoing TPRK in a clinical setting. Preoperative and postoperative data on ophthalmic and Corvis ST examinations, in vivo Young’s modulus, and noncontact tonometry were analyzed. Marginal linear regression models with generalized estimating equations were used for intragroup and intergroup comparisons of IOP and bIOP changes. Results. In the univariate model, IOP reduction after FS-LASIK was 2.49 mmHg higher than that after TPRK. In addition, bIOP reduction after FS-LASIK was 1.85 mmHg higher than that after TPRK. In the multiple regression model, we revealed that IOP reduction after FS-LASIK was 1.75 mmHg higher than that after TPRK. Additionally, bIOP reduction after FS-LASIK was 1.64 mmHg higher than that after TPRK. Postoperative changes in bIOP were less than those in IOP. In addition, Young’s modulus and CBI had no significant effect on postoperative IOP and bIOP changes. We establish a biomechanically predictive model using the available data to predict postoperative IOP and bIOP changes after TPRK and FS-LASIK. Conclusions. Reductions in IOP and bIOP after FS-LASIK were 1.75 mmHg and 1.64 mmHg, respectively, more than those after TPRK, after adjustment for confounders. We revealed that the type of refractive surgery and peak distance (PD) were significant predictors of postoperative IOP and bIOP changes. By contrast, depth of ablation showed a significant effect on only IOP changes.

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