scholarly journals Effect of treatment zone diameter on the clinical results of femtosecond laser-assisted in situ keratomileusis and trans-photorefractive keratectomy for the correction of myopia

2018 ◽  
Vol 1 (1) ◽  
pp. 3-8
Author(s):  
Assaf Gershoni ◽  
Sabaa Knaneh ◽  
Michael Mimouni ◽  
Eitan Livny ◽  
Irit Bahar ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Clinical Results ◽  
Photorefractive Keratectomy ◽  
Zone Diameter ◽  
Treatment Zone ◽  
Effect Of Treatment

scholarly journals Surface Ablation Techniques for Myopia – A Review of the Advances Over the Past 25 Years

2017 ◽  
Vol 11 (01) ◽  
pp. 31
Author(s):  
Jesper Hjortdal ◽  
Keyword(s):  
Excimer Laser ◽  
Clinical Results ◽  
Review Article ◽  
Ablation Techniques ◽  
Photorefractive Keratectomy ◽  
Excimer Lasers ◽  
The Past ◽  
Surface Ablation ◽  
Meta Analyses

Photorefractive keratectomy for correction of myopia was the first excimer laser-based technique to be developed. During the last 25 years, excimer lasers have improved technologically, several variations of the technique have been developed and pre- and postoperative pharmaceutical therapies have been investigated. This review article summarises these developments and the published meta-analyses on comparison of surface ablation techniques and laser in situ keratomileusis. The main conclusion is that there seem to be no differences between the clinical results obtained with the different variations of surface ablation techniques.

The surgery correction of presbyopia: the modern possibilities

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.

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

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.

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

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.

Femtosecond laser assisted in situ keratomileusis (FS-LASIK) yields better results than transepithelial photorefractive keratectomy (Trans-PRK) for correction of low to moderate grade myopia

2020 ◽  
pp. 112067212098034
Author(s):  
Assaf Gershoni ◽  
Olga Reitblat ◽  
Michael Mimouni ◽  
Eitan Livny ◽  
Yoav Nahum ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Outcome Data ◽  
Photorefractive Keratectomy ◽  
Efficacy And Safety ◽  
Safety Index ◽  
Cohort Study Design ◽  
Safety Parameters ◽  
Efficacy Index ◽  
In Trans

Introduction: The purpose of this study was to compare the outcomes of transepithelial photorefractive keratectomy (Trans-PRK) with femtosecond laser assisted in situ keratomileusis (FS-LASIK) for the correction of low to moderate myopia. Methods: A retrospective cohort study design was used. The study group included patients with myopia less than −6.0 D, with or without concomitant astigmatism under 2.0 D, who were treated with FS-LASIK or Trans-PRK in 2013 through 2014. Background, clinical and outcome data were collected from the patient files. A comparison between eyes treated with FS-LASIK or Trans-PRK was performed. Results: The Trans-PRK group was comprised of 1793 eyes and the FS-LASIK group of 666 eyes. Mean ± SD spherical equivalent (SE) refraction prior to surgery was −3.43 ± 1.27 D in the Trans-PRK group and −3.18 ± 1.34 D in the FS-LASIK group ( p < 0.001). Efficacy index values were 0.95 ± 0.14 in the Trans-PRK group and 0.98 ± 0.12 in the FS-LASIK group ( p < 0.001), and corresponding safety index values were 0.96 ± 0.13 and 0.99 ± 0.12 ( p < 0.001). Distance from target refraction was 0.45 ± 0.42 D in Trans-PRK group and 0.43 ± 0.38 D in the FS-LASIK group ( p = 0.537); 71.6% and 74.2% of eyes were within ±0.5 D of attempted correction, respectively ( p = 0.193) Conclusions: Both Trans-PRK and FS-LASIK demonstrated excellent results, mostly comparable with the current literature. FS-LASIK achieved better results than Trans-PRK surgery in the efficacy and safety parameters.

scholarly journals Changes in custom biomechanical variables after femtosecond laser in situ keratomileusis and photorefractive keratectomy for myopia

2014 ◽  
Vol 40 (6) ◽  
pp. 918-928 ◽  
Author(s):  
Marcony R. Santhiago ◽  
Steven E. Wilson ◽  
Katie M. Hallahan ◽  
David Smadja ◽  
Michelle Lin ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Laser In Situ Keratomileusis ◽  
Photorefractive Keratectomy
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