Search Our Scientific Publications & Authors

Clin Ophthalmol 2021 23;15:1735-1749. Epub 2021 Apr 23.

Ophthalmology Department, Cairo University, Cairo, Egypt.

Purpose Of The Study: To compare visual outcome, higher order aberrations (HOAs) of topography guided and Q value adjusted ablation in the fellow eye of patients undergoing photorefractive keratectomy (PRK) for the correction of myopia and myopic astigmatism.

Methods: Prospective randomized controlled interventional clinical study. The eyes of 52 patients undergoing PRK for myopia and astigmatism were included, that is, 104 eyes in total. Read More

Ophthalmic Physiol Opt 2021 Apr 20. Epub 2021 Apr 20.

State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.

Purpose: Extensive clinical evidence suggests that time spent outdoors might reduce the risk of myopia. This study aimed to determine whether increasing sunlight exposure has a protective effect on hyperopic-defocus induced myopia in a non-human primate.

Methods: Twelve 2-month-old rhesus monkeys were treated monocularly with photorefractive keratectomy (PRK) (4. Read More

BMC Ophthalmol 2021 Apr 16;21(1):181. Epub 2021 Apr 16.

Augenlaserzentrum Neu-Ulm, Edisonallee 19, 89231, Neu-Ulm, Germany.

Purpose: To compare early clinical outcomes of single-step transepithelial photorefractive keratectomy (tPRK) and photorefractive keratectomy (PRK) regarding refractive outcome, visual acuity, wound healing, pain intensity and visual recovery time.d.

Methods: In this prospective clinical observational study 200 eyes of 100 consecutive patients with mild to moderate myopia with or without mild astigmatism were included. Read More

J Fr Ophtalmol 2021 Apr 12. Epub 2021 Apr 12.

Ophthalmology department, College of medicine, King Saud University, Riyadh, Saudi Arabia. Electronic address:

Objectives: To study corneal haze following myopic photorefractive keratectomy (PRK) in a high-risk population and to assess methods for minimizing the risk.

Methods: The medical records of 150 patients who underwent PRK were reviewed. A total of 300 eyes were included. Read More

J Fr Ophtalmol 2021 Apr 6. Epub 2021 Apr 6.

Service d'ophtalmologie, Hôpital d'instruction des Armées Percy, 101, avenue Henri-Barbusse, BP 406, 92141 Clamart cedex, France; École du Val-de-Grâce, 1, place Alphonse-Laveran, 75230 Paris cedex 05, France.

Hyperopia is a refractive error in which light is focused behind, instead of on, the retina. Clear vision can be obtained by accommodation, but in the long run, this results in eye strain. Hyperopia can be classified as low [≤2. Read More

Int Ophthalmol 2021 Mar 24. Epub 2021 Mar 24.

Department of Ophthalmology, College of Medicine, King Saud University, Airport Road, P.O. Box 245, Riyadh, 11411, Saudi Arabia.

Purpose: To assess the safety and effectiveness of transepithelial photorefractive keratectomy (T-PRK) in patients with mild myopia using the Schwind Amaris 750 s Excimer laser system which take corneal epithelium variability in consideration during ablation.

Methods: A prospective case series study of patients with mild myopia with or without astigmatism (spherical equivalent ≤ -3 diopters), who underwent T-PRK as a single-step treatment, was carried out at King Abdulaziz University Hospital, Riyadh between May 2017 and January 2018. The main outcomes included postoperative uncorrected distance visual acuity (UDVA), residual refraction (manifest refraction) and complications. Read More

J Med Case Rep 2021 Mar 16;15(1):122. Epub 2021 Mar 16.

Takayanagi EYE Clinic, Sapporo S1 Building 3F, Nishi4-20-5, Minami1-jo, Chuo-ku, Sapporo, Hokkaido, 060-0807, Japan.

Background: Corneal refractive surgeries cause epithelial damage and induce wound healing processes. To promote wound healing after photorefractive keratectomy, the effectiveness of an autologous platelet tissue graft was assessed.

Case Presentation: A 45-year-old Asian male with low myopia and/or myopic astigmatism received photorefractive keratectomy in both eyes. Read More

Mil Med 2021 Feb 25. Epub 2021 Feb 25.

Navy Refractive Surgery Center, Naval Medical Center San Diego, San Diego, CA 92134, USA.

Introduction: Femtosecond-assisted thin flap, laser-assisted in situ keratomileusis (LASIK) and photorefractive keratectomy with mitomycin-C (PRK-MMC) are the two most common refractive surgical procedures used to enhance visual capability in the U.S military. The purposes of the study were to examine effects on quality of vision following LASIK and PRK-MMC using a novel computer-based quick contrast sensitivity function (qCSF) test. Read More

J AAPOS 2021 Feb 20. Epub 2021 Feb 20.

John F. Hardesty, MD, Department of Ophthalmology and Visual Sciences, Washington University in St. Louis School of Medicine, St. Louis, Missouri; Department of Pediatrics, Washington University in St. Louis School of Medicine, St. Louis, Missouri; Department of Neuroscience, Washington University in St. Louis School of Medicine, St. Louis, Missouri. Electronic address:

Purpose: To analyze outcomes in a large cohort of spectacle-aversive children with high myopia who were treated by implantation of the Ophtec-Artisan or Visian phakic intraocular lens (pIOL).

Methods: Outcome data were collated retrospectively in 78 children (115 eyes) implanted with the Ophtec-Artisan iris-enclaved anterior chamber pIOL and 91 children (154 eyes) implanted with the Visian ICL (intraocular collamer lens) sulcus pIOL. All children had difficulties with spectacle or contact lens wear. Read More

Ther Adv Ophthalmol 2021 Jan-Dec;13:2515841420988215. Epub 2021 Jan 22.

University Eye Hospital, Ruhr-University Bochum, Bochum, Germany.

Purpose: In Epi-Bowman Keratectomy™ (EBK), a new dynamic multi-blade single-use device (Epi-Clear™, Orca Surgical, Israel) is utilized to remove the epithelium by sweeping movements across the corneal surface. Epithelial cells are discarded. Alcohol or other chemical agents are not utilized. Read More

Vision (Basel) 2021 Feb 3;5(1). Epub 2021 Feb 3.

AURELIOS, Augenlaserzentrum Recklinghausen, Erlbruch 34-36, 45657 Recklinghausen, Germany.

Purpose: We evaluated the refractive visual outcomes and efficacy of Transepithelial Photorefractive Keratectomy (TransPRK) using Smart Pulse Technology with static and dynamic cyclotorsion and the AMARIS 1050 Hz RS laser platform from Schwind in the eyes after a refractive lens exchange. Setting/Venue: Aurelios Augenlaserzentrum, Recklinghausen.

Methods: We retrospectively evaluated the data of 552 consecutive eyes treated with refractive lens exchange between 2016 and 2019. Read More

Ophthalmology 2021 May 24;128(5):781-792. Epub 2021 Jan 24.

Francis I. Proctor Foundation and Department of Ophthalmology, University of California, San Francisco, California.

Purpose: To review the literature to evaluate the outcomes of intraocular lens (IOL) power calculation in eyes with a history of myopic LASIK or photorefractive keratectomy (PRK).

Methods: Literature searches were conducted in the PubMed database in January 2020. Separate searches relevant to cataract surgery outcomes and corneal refractive surgery returned 1169 and 162 relevant citations, respectively, and the full text of 24 was reviewed. Read More

Medicine (Baltimore) 2021 Jan;100(2):e23769

Aier School of Ophthalmology, Central South University, Changsha.

Abstract: To compare the safety and efficiency of simple corneal topography-guided (T-CAT) photorefractive keratectomy (PRK) and T-CAT PRK combined with crosslinking (CXL) to correct myopia with borderline suspicious tomography.Eyes with suspicious tomography (not classified as forme fruste keratoconus) underwent PRK combined with CXL. The suspicious tomography showed irregular posterior corneal morphology or maximum elevation value of the central 6 mm zone of the posterior surface (MEL) >15 μm, or Belin/Ambrósio Enhanced Ectasia Index (BAD-D) was >1. Read More

Acta Inform Med 2020 Sep;28(3):180-184

Department of Ophthalmology, Rijeka University Hospital, Rijeka, Croatia.

Introduction: T Transepithelial photorefractive keratectomy (T-PRK) and femtosecond laser in situ keratomileusis (Fs-LASIK) are reftactive surgery methods for treating myopia and myopic astigmatism. Although T-PRK obtains similar results to Fs-LASIK with spherical myopia, it has differences in astigmatism correction. Vector analysis is a perfect tool to see the real difference between these two methods regarding astigmatic refraction and visual acuity. Read More

Cell Tissue Bank 2021 Jan 4. Epub 2021 Jan 4.

Laboratory for Corneal Graft Biology, engineering and imaging (BiiGC, EA2521), Faculty of Medicine, University Jean Monnet, Health Innovation Campus, 10 rue de la marandière, F-42055, Saint-Etienne, France.

The detection of corneas operated on for refractive surgery [LASIK or photorefractive keratectomy (PRK)] will become a major concern for eye banks in the coming years because this surgery is often forgotten during the interview with the deceased's relatives. We present here 2 corneas operated on with PKR and stored successively in organ culture (OC) and in the active storage machine (ASM) that restores intraocular pressure, restores the cornea to its original shape, respects transparency and incorporates non-invasive controls. The 2 corneas of a 49-year-old donor operated 17 years earlier by PRK for -2 and -3 diopters myopia were stored in OC for 14 days and then placed in ASM for 48 h. Read More

Int J Ophthalmol 2020 18;13(12):1955-1960. Epub 2020 Dec 18.

Center of Excellence in Ophthalmology, Pará de Minas 35660-051, Brazil.

Aim: To evaluate the clinical results after implantation of a new intrastromal corneal ring segment (ICRS) associated with photorefractive keratectomy (PRK) to correct high myopia (HM) patients with thin corneas.

Methods: We evaluated 42 eyes of 23 HM patients that had ICRS implantation followed by PRK. The mean age of patients was 29. Read More

Cochrane Database Syst Rev 2020 12 18;12:CD012687. Epub 2020 Dec 18.

Department of Ophthalmology, University of Colorado Anschutz Medical Campus, Denver, Colorado, USA.

Background: Refractive errors (conditions in which the eye fails to focus objects accurately on the retina due to defects in the refractive system), are the most common cause of visual impairment. Myopia, hyperopia, and astigmatism are low-order aberrations, usually corrected with spectacles, contact lenses, or conventional refractive surgery. Higher-order aberrations (HOAs) can be quantified with wavefront aberration instruments and corrected using wavefront-guided or wavefront-optimized laser surgery. Read More

Acta Ophthalmol 2020 Dec 16. Epub 2020 Dec 16.

School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China.

Purpose: To evaluate the anti-haze effect and visual outcome after intraoperative mitomycin C (MMC) use during photorefractive keratectomy (PRK) in myopia or myopic astigmatism patients.

Methods: We searched in PubMed, EMBASE, Cochrane Library and Google Scholar comprehensively to obtain studies comparing the clinical effects after PRK with and without MMC published until February 2020. Meta-analysis of primary outcome (corneal haze rate) and secondary outcomes [predictability, efficacy, safety and corneal endothelial cell density (ECD)] were conducted. Read More

Eur J Ophthalmol 2020 Dec 14:1120672120980346. Epub 2020 Dec 14.

Assuta Optic Laser Center, Assuta Medical Center, Tel Aviv, Israel.

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. Read More

J Refract Surg 2020 Dec;36(12):844-850

Purpose: To determine the volumes altered during photorefractive keratectomy (PRK), laser in situ keratomileusis (LASIK), and small incision lenticule extraction (SMILE) correction of myopia and myopic astigmatism.

Methods: The volumes of stromal tissue affected by surgical correction of pure and astigmatic myopia were calculated in this theoretical study for PRK, LASIK, and SMILE treatments. These results were then used to calculate representative values for percent volume altered (PVA) restricted to stromal corneal tissue. Read More

J Cataract Refract Surg 2020 12;46(12):1644-1651

From the Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.

Purpose: To investigate repeatability and agreement of total corneal and sublayer pachymetry with 2 different algorithms of Fourier-domain optical coherence tomography (OCT) in myopic and postphotorefractive keratectomy (PRK) eyes.

Setting: Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.

Design: Prospective observational study. Read More

Int J Environ Res Public Health 2020 11 24;17(23). Epub 2020 Nov 24.

Department of Ophthalmology, Hospital de Poniente, 04700 Almeria, Spain.

(1) Background: Refractive surgery is an increasingly popular procedure for decreasing spectacle or contact lens dependency. The two most common surgical techniques to correct myopia are photorefractive keratectomy (PRK) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK). This study demonstrates the long-term effectiveness, safety, and predictability of both techniques for the refractive surgery of myopia. Read More

Eur J Ophthalmol 2020 Nov 25:1120672120974946. Epub 2020 Nov 25.

Dhami Eye Care Hospital, Ludhiana, Punjab, India.

Purpose: To report a case series of anterior uveitis after Transepithelial Photorefractive Keratectomy (TransPRK) and determine its incidence, demographics and associated clinical features over a study period of 1 year.

Methods: This retrospective case series comprised of 200 eyes (100 patients) which underwent elective TransPRK surgery for ametropia correction at a tertiary eye care center by two refractive surgeons over 1 year. TransPRK was performed on Streamlight software (EX500, Alcon Wavelight, Inc. Read More

Bull Exp Biol Med 2020 Nov 24;170(1):79-83. Epub 2020 Nov 24.

Huashan Eye Hospital of Kunming, Kunming, Yunnan Province, PR China.

We compared the level of transforming growth factor-β1 (TGF-β1) in the tear fluid of 20 patients with high myopia who underwent transepithelial photorefractive keratectomy (T-PRK) in one eye and laser subepithelial keratomileusis (LASEK) in the contralateral eye. Tear fluid samples were collected with scaled microcapillary tubes before (day 0) and on days 1, 3, and 5 after surgery. The release of TGF-β1 was determined by multiplying the concentration of TGF-β1 by capillary tear fluid flow. Read More

Indian J Ophthalmol 2020 Dec;68(12):2940-2944

Department of Ophthalmology, Health Sciences University Haydarpasa Numune Training and Research Hospital, Istanbul, Turkey.

Purpose: The aim of this study was to evaluate visual quality after high-frequency transepithelial photorefractive keratectomy (t-PRK) by assessing the relationship between the operational parameters and the first-year postoperative corneal higher-order aberrations (HOAs).

Methods: This was a retrospective study of low-to-moderate myopic eyes treated with t-PRK. The files of 46 low-to-moderate myopic patients (90 eyes; myopia up to -5D) were included in the study. Read More

Indian J Ophthalmol 2020 Dec;68(12):2847-2855

Department of Cataract and Refractive Surgery, Narayana Nethralaya, Bangalore, Karnataka, India.

Over the past two decades, excimer laser-based refractive surgery procedures have been successfully established for their safety and satisfactory visual outcomes. Surface ablation procedures or photorefractive keratectomy (PRK) are practised commonly for the correction of refractive errors including myopia, astigmatism and hyperopia. Satisfactory visual outcomes are achieved in majority of cases, although a very small percentage have issues related to corneal haze, regression, and its associated visual disturbances. Read More

Indian J Ophthalmol 2020 Dec;68(12):2691-2698

International Medical Research Association (IMedRA); Faculty of Medicine, Al-Azhar University, Cairo, Egypt.

Photorefractive keratectomy (PRK) eye surgery is widely used for patients at risk for corneal ectasia to maintain an aspheric corneal shape. Wavefront-guided (WFG) ablation profile was designed to reduce pre-existing higher-order aberrations (HOA). We aimed to compare the corneal aberrations and visual outcomes between WFG and Wavefront Optimized (WFO) PRK in patients with myopia. Read More

PLoS One 2020 11;15(9):e0238399. Epub 2020 Sep 11.

Department of Ophthalmology, Miguel Servet University Hospital, Zaragoza, Spain.

Purpose: To analyze the influence of the final spherical equivalent (SE) in LogMAR uncorrected distance visual acuity (UDVA) one year after refractive surgery. We analysed refractive results, their predictability and efficacy, and the safety results of the different methods as secondary outcomes.

Setting: Refractive Surgery Unit of the Institut Català de Retina (ICR) in Barcelona, Spain. Read More

Exp Eye Res 2020 11 6;200:108218. Epub 2020 Sep 6.

The Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA. Electronic address:

This review details the current understanding of the mechanism of action and corneal effects of mitomycin C (MMC) for prophylactic prevention of stromal fibrosis after photorefractive keratectomy (PRK), and includes discussion of available information on dosage and exposure time recommended for MMC during PRK. MMC is an alkylating agent, with DNA-crosslinking activity, that inhibits DNA replication and cellular proliferation. It acts as a pro-drug and requires reduction in the tissue to be converted to an active agent capable of DNA alkylation. Read More

Int Ophthalmol 2021 Jan 8;41(1):303-314. Epub 2020 Sep 8.

Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou, 515041, China.

Purpose: To evaluate the clinical outcomes of small incision lenticule extraction (SMILE) and aberration-free transepithelial photorefractive keratectomy (AF t-PRK) in patients with low to moderate myopic astigmatism, including visual acuity, refractive outcomes, astigmatic vector analysis and corneal aberrometric changes.

Method: This retrospective comparative case series study involved 110 right eyes of 110 patients who underwent either SMILE (55 eyes) or AF t-PRK (55 eyes). Visual acuity, manifest refractive error and corneal higher-order aberrations (HOAs) were measured and analyzed at baseline, 1 month and 3 months after operation. Read More