Publications by authors named "Ahmet Demirok"
Purpose: To evaluate the changes in anterior chamber dimensions including horizontal anterior chamber diameter (HACD), anterior chamber depth (ACD), and iridocorneal angle (ICA) following small incision lenticule extraction (SMILE) using Scheimpflug-Placido disk tomographer (Sirius).
Methods: The records of the 73 eyes of 47 patients who received SMILE for myopia and myopic astigmatism were retrospectively reviewed. Preoperative and 6-month postoperative measurements of central corneal thickness (CCT), HACD, ACD, ICA, nasal anterior chamber angle (nACA), and temporal anterior chamber angle (tACA) were obtained by tomography, and compared with paired t-tests.
In June 2020, a 28-year-old female patient was admitted to our clinic with reduced vision in the left eye. She had systemic COVID-19 infection in May 2020 and during her treatment course, her visual complaints had begun approximately 1 week after the beginning of the COVID-19. Previously, the patient had bilateral femtosecond assisted - Laser in situ Keratomileusis in our clinic in 2018.
View Article and Find Full Text PDFObjectives: This study was designed to evaluate the effects of corneal collagen cross-linking (CXL) on topographic parameters, visual acuity, and corneal high-order aberrations according to the preoperative cone location in keratoconus.
Methods: This retrospective study assessed patients with keratoconus who underwent CXL between March 2016 and February 2019. Patients with a history of corneal surgery, corneal hydrops, corneal scar tissue, delayed epithelial healing, and a corneal thickness of <400 μm were excluded.
Described herein are the cases of 2 patients who underwent bilateral femtosecond-assisted laser in situ keratomileusis (FS LASIK) surgery and subsequently developed unilateral postLASIK ectasia. The fellow eye of both patients was topographically normal, their visual acuity was 20/20, and the patients had no visual symptoms. However, a biomechanical assessment using the Corvis ST tonometer (Oculus Optikgerate GmbH; Wetzlar, Germany) revealed remarkable weakness not only in the ectatic eyes, but also in the fellow eye.
View Article and Find Full Text PDFBackground: To evaluate the microvascularity and choroidal vascularity index (CVI) using optical coherence tomography angiography (OCTA) and OCT following femtosecond laser-assisted in-situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) procedures.
Methods: Patients with myopia (<-6.0D sphere) or myopic astigmatism (<-4.
Purpose: To evaluate long-term visual and refractive outcomes of corneal wavefront-guided transepithelial photorefractive keratectomy (t-PRK) with mitomycin C for the treatment of corneal opacities secondary to adenoviral epidemic keratoconjunctivitis.
Methods: Records of patients who underwent corneal wavefront-guided t-PRK with excimer laser from January 2012 to December 2018 were retrospectively reviewed. Preoperative and postoperative uncorrected visual acuity, best-spectacle corrected visual acuity, slit-lamp biomicroscopic examination findings, manifest refraction, and corneal aberrations and fundus examination findings were evaluated.
Purpose: To evaluate the effect of topical omega 3 on ocular surface following corneal crosslinking (CXL) in keratoconus and compare with topical sodium hyaluronate.
Material Methods: 50 patients who underwent CXL were divided into two groups. In addition to topical steroids and antibiotics, Group A was prescribed topical omega 3; Group B was prescribed 0.
Objectives: To report the refractive and visual outcomes of small incision lenticule extraction (SMILE) with the thinnest corneal thickness (CCT) of less than 500 µm and evaluate it in terms of safety and efficacy.
Setting: Refractive Surgery Clinic of University of Health Sciences Beyoglu Eye Training and Research Hospital, Istanbul, Turkey.
Design: Retrospective case series.
Objective: The objective of this study is to evaluate the repeatability and reliability of corneal parameters in different stages of keratoconus patients using a combined Scheimpflug-Placido disc analysis system.
Materials And Methods: In this prospective study, three consecutive measurements were performed by the same observer using Scheimpflug-Placido disc anterior segment analysis device in keratoconus patients. Flattest and steepest simulated keratometry and corneal volume, corneal aberrations, thinnest corneal thickness, symmetry index, keratoconus vertex and Baiocchi-Calossi-Versaci index were recorded.
Purpose: To compare the long-term safety, efficacy, and complications of small-incision lenticule extraction (SMILE) and flexible iris-fixated anterior chamber phakic intraocular lens (pIOL) implantation for the treatment of high myopia.
Setting: University of Health Science Turkey, Beyoğlu Eye Training and Research Hospital, İstanbul, Turkey.
Design: Retrospective comparative case series.
Article Synopsis
- The study aimed to assess early and late complications from accelerated cross-linking (A-CXL) in keratoconus patients and their link to other health conditions.
- A review of 2025 eyes from 1184 patients showed that early complications included haze formation (9.1%), while late-stage issues involved treatment failure (4.2%), with vernal keratoconjunctivitis being the most common accompanying condition (3.7%).
- The results indicate that patients with vernal keratoconjunctivitis face a higher risk of delayed epithelial healing, and those with Down syndrome are more likely to experience corneal haze and sterile infiltrates following A-CXL.
Background: Attention is usually given to inferior steepening on corneal topography in the evaluation of a patient's suitability for LASIK surgery. The aim of this study is to investigate long-term refractive results with superior steepening.
Methods: Patients who underwent LASIK surgery between 2015 and 2019 in our refractive surgery department were retrospectively reviewed.
We describe a combined technique of trocar-assisted sutureless scleral-fixated intraocular lens implantation and silicone oil injection at the same session. Two 3 mm scleral tunnels were created 2 mm away from and parallel to the limbus with the 23-gauge vitrectomy trocars entering the sclera transconjunctivally at an angle of approximately 10° at the 3 o'clock and 9 o'clock meridians. After the 3-piece foldable IOL was delivered to the anterior chamber through the corneal incision, the tip of one of the IOL haptics was grasped with a 23-gauge serrated retinal forceps entered through the trocar located at the 3 o'clock meridian.
View Article and Find Full Text PDFDescemet's membrane endothelial keratoplasty in aphakic and vitrectomized eye.
GMS Ophthalmol Cases
February 2020
To report a new technique for Descemet's membrane endothelial keratoplasty (DMEK) in aphakic and vitrectomized eyes. A 56-year-old man presented with corneal decompensation in the left eye after combined pars plana vitrectomy and lensectomy for the management of a traumatic eye injury. DMEK graft and recipient bed were prepared as regular.
View Article and Find Full Text PDFPurpose: To compare the long-term refractive and visual outcomes and the corneal higher-order aberrations of contralateral eyes of patients who received small-incision lenticule extraction (SMILE) in one eye and femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) in the other eye.
Setting: Refractive Surgery Clinic of the University of Health Sciences Beyoğlu Eye Training and Research Hospital, Istanbul, Turkey.
Design: Retrospective case series.
Objectives: Branch retinal vein occlusion (BRVO) is the second most common type of retinal vascular disorder. Both inflammation and increased vascular endothelial growth factor (VEGF) levels play important roles in the pathogenesis of macular edema (ME) secondary to BRVO. The aim of this study was to compare the efficacy of 0.
View Article and Find Full Text PDFPurpose: To report long-term efficacy and safety of small-incision lenticule extraction (SMILE) in patients with mild-to-moderate myopia.
Setting: Beyoglu Eye Training and Research Hospital, İstanbul, Turkey.
Design: Retrospective case series.
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.
Purpose: To evaluate the visual, refractive, and topographic outcomes after simultaneous topography-guided transepithelial photorefractive keratectomy (transepithelial TG-PRK) using the Amaris Excimer laser platform and accelerated corneal cross-linking (CXL) in eyes with keratoconus.
Materials And Methods: Patients with 2 years of follow-up were included in this retrospective case series. Manifest refraction (MR), uncorrected (UDVA) and corrected (CDVA) distance visual acuity, corneal topography, and pachymetry were evaluated at 1, 3, 6, 12, and 24 months after surgery.
To evaluate the outcome after astigmatic correction of small incision lenticule extraction (SMILE) and to compare the refractive results of right eyes with left eyes. Patients who underwent SMILE surgery in our clinic between 2014 and 2016 (Visumax, Carl Zeiss Meditec, Germany) were retrospectively reviewed. Preoperative and postoperative manifest refractions and corrected and uncorrected visual acuities were evaluated and changes in refractive astigmatism were evaluated by vector analysis.
View Article and Find Full Text PDFPurpose: To report clinical results of a foldable, hydrophilic acrylic, single-piece, injectable, posterior chamber phakic intraocular lens (pIOL).
Material And Methods: Medical records of patients who underwent posterior chamber phakic IOL (Eyecryl Phakic IOL, Biotech Vision Care, Ahmedabad, India) implantation for surgical correction of myopia were retrospectively reviewed. Only patients with at least a one-year follow-up were included.
Purpose We describe a scleral suture fixation technique for dislocated plate haptic toric intraocular lens (IOL) implantation. Materials and methods A double-armed 10-0 straight polypropylene suture was passed into the eye from the sclera (2 mm away from the limbus). A suture needle was passed through the hole on the corner of the IOL and pulled out from the paracentesis with a 27-gauge needle.
View Article and Find Full Text PDFPurpose: To investigate how corneal aberrations change after phototherapeutic keratectomy (PTK) for subepithelial infiltrates after adenoviral keratoconjunctivitis.
Methods: The records of patients who underwent transepithelial PTK for subepithelial infiltrates were retrospectively reviewed. Preoperative best-corrected visual acuity (VA) and the results of slit-lamp biomicroscopy examinations were recorded.
Purpose: To compare the results of different protocols for accelerated corneal collagen cross-linking (CXL) in patients with progressive keratoconus.
Materials And Method: This prospective comparative study involved 40 patients treated with intended UV-A radiance of 5.4 J/cm in 74 eyes (Group 1) and 42 patients treated with radiance of 7.