Publications by authors named "Eui Sang Chung"
We propose FD3, a fundus image enhancement method based on direct diffusion bridges, which can cope with a wide range of complex degradations, including haze, blur, noise, and shadow. We first propose a synthetic forward model through a human feedback loop with board-certified ophthalmologists for maximal quality improvement of low-quality in-vivo images. Using the proposed forward model, we train a robust and flexible diffusion-based image enhancement network that is highly effective as a stand-alone method, unlike previous diffusion model-based approaches which act only as a refiner on top of pre-trained models.
View Article and Find Full Text PDFBackground: This study aimed to compare the clinical outcomes of implantation of various multifocal intraocular lenses (mIOLs) and the prediction accuracy of two intraocular lens (IOL) power calculation formulas for eyes that underwent previous corneal refractive surgery.
Methods: Four types of mIOLs [TECNIS Symfony (Group I), AcrySof IQ PanOptix (Group II), LENTIS Mplus (Group III), and TECNIS ZLB00 (Group IV)] were used and the IOL power was calculated with the two no-history methods, Shammas-PL and Barrett True-K. Visual acuity and refractive outcomes including manifest refraction, prediction error (PE), absolute error (AE), and median absolute error (MedAE) were evaluated at three months after the cataract surgery.
Purpose: To report the long-term clinical outcomes, including efficacy and safety, of implantable collamer lens (ICL) implantation to treat myopia.
Setting: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Design: Retrospective case series.
Purpose: To present the incidence, risk factors, and effect of opaque bubble layer (OBL) formation during flap creation in laser-assisted in situ keratomileusis (LASIK) with a 500-kHz femtosecond laser on visual performance.
Methods: In this retrospective study, preoperative characteristics (age, sex, keratometric value, spherical equivalent, and central corneal thickness) and intraoperative surgical factors (used energy, docking type, and flap thickness) were compared between eyes with and without OBL formation during flap creation. Possible risk factors for specific types of OBLs were analyzed.
Purpose: To evaluate and compare published methods of calculating intraocular lens (IOL) power following myopic laser refractive surgery.
Methods: We performed a retrospective review of the medical records of 69 patients (69 eyes) who had undergone myopic laser refractive surgery previously and subsequently underwent cataract surgery at Samsung Medical Center in Seoul, South Korea from January 2010 to June 2016. None of the patients had pre-refractive surgery biometric data available.
Purpose: To report the long-term results of temporary piggyback IOL implantation in congenital cataract and to compare the clinical outcomes of temporary piggyback IOL with those of single IOL implantation.
Methods: This is a retrospective, comparative, interventional study. The medical records of all consecutive patients who underwent cataract extraction and single or temporary piggyback IOL implantation within the first 3 years of life from 1999 to 2013 at Samsung Medical Center were reviewed.
Aim: To assess visual quality after presbyopia correction using an aspheric ablation profile and a micro-monovision protocol.
Methods: This is a retrospective interventional study. Fifty-four eyes of 27 patients (mean age, 50.
Background: The purpose of this study was to identify factors related to the unexpected vault in V4c implantable collamer lens (ICL; STAAR Surgical) implantation.
Methods: V4c ICLs were implanted in 43 eyes of 43 patients for the correction of myopia. The implanted V4c ICL sizes were determined individually with our previous V4 ICL sizing nomogram based on the sulcus-to-sulcus diameter (STS), and the V4 ICL sizes were then converted to V4c ICL sizes with a size-converting table.
Purpose: To compare the efficacy and rotational stability after implantation of two types of toric implantable collamer lenses (Toric ICL™(TICL);V4 and V4c, STAAR Surgical Co.).
Study Design: Retrospective case series.
Purpose: In the present study, the incidence and risk factors of lens-iris diaphragm retropulsion syndrome (LIDRS) were evaluated.
Methods: Patients who underwent cataract surgery using phacoemulsification between June 2014 and December 2014 were included in the study. The preoperative ocular biometric and intraoperative surgical parameters were examined.
Purpose: To estimate the genetic influences on corneal and ocular higher-order aberrations (HoAs) in the Korean population.
Methods: This was a prospective, family-based twin cohort study. A total of 1272 adult twins and their family members, who were part of the Korean Healthy Twin Study from 2007-2011, were included.
Background: Mutations in the transforming growth factor β-induced gene (TGFBI) are major causes of genetic corneal dystrophies (CDs), which can be grouped into TGFBI CDs. Although a few studies have reported the clinical and genetic features of Korean patients with TGFBI CD, no data are available regarding the frequency and spectrum of TGFBI mutations in a consecutive series of Korean patients with clinically diagnosed CDs.
Methods: Patients with any type of CD, who underwent both ophthalmologic examination and TGFBI gene analysis by Sanger sequencing at a tertiary care hospital in Seoul, Korea from 2006 to 2013, were enrolled in this study.
Purpose: To investigate stemness characteristics of human corneal endothelial cells (HCECs) cultured in various media.
Methods: Human corneal endothelial cells were isolated using a sphere-forming assay. Cells were allowed to attach to the bottom of culture plates and were cultured in different media designated as medium A (Opti-MEM I with 8% fetal bovine serum), medium B (DMEM/F12 with B27 supplement), medium E (DMEM/F12 with epidermal growth factor [EGF]), and medium BE (DMEM/F12 with B27 supplement and EGF), respectively.
Purpose: To assess Pentacam (Oculus, Wetzlar, Germany) Scheimpflug quantitative images in evaluating lens density and providing objective measurements to suggest optimal time of cataract surgery in the field of health examination.
Methods: Two hundred and twenty-nine eyes with age-related cataract were enrolled. Lens density was measured using Pentacam.
The effects of different culture media on human corneal endothelial cells.
Invest Ophthalmol Vis Sci
July 2014
Purpose: To investigate the most appropriate media condition for the proliferation and functional maintenance of human corneal endothelial cells (HCECs).
Methods: We cultured HCECs in traditional media (medium A or D) and in stem cell media (medium E or N). The morphology of the cells was evaluated by inverted microscopy.
Purpose: To investigate visual outcomes of Visian implantable Collamer lens (ICL) implantation in eyes with a shallow anterior chamber depth (ACD).
Design: Retrospective, noncomparative, interventional case series.
Methods: Medical charts of the patients with a low ACD of 2.
Purpose: To evaluate the clinical efficacy of newly developed guidelines for the diagnosis and management of dry eye.
Methods: This retrospective, multi-center, non-randomized, observational study included a total of 1,612 patients with dry eye disease who initially visited the clinics from March 2010 to August 2010. Korean guidelines for the diagnosis and management of dry eye were newly developed from concise, expert-consensus recommendations.
Purpose: Corneal endotheliitis causes endothelial decompensation and is associated with significant visual impairment. The goal of this article is to report a case of corneal endotheliitis associated with coxsackievirus A24 infection after cataract surgery in a patient who had no previous symptoms indicative of conjunctivitis.
Methods: A 55-year-old man was admitted for cataract surgery when acute hemorrhagic conjunctivitis was prevalent.
Purpose: To evaluate the incidence and clinical manifestations of intraoperative floppy iris syndrome (IFIS) according to iris alterations in Korean patients taking α1-adrenergic receptor antagonists (α1-ARAs).
Methods: This is a prospective observational study. Two surgeons performed cataract surgery in 758 eyes of 596 patients over a period of 12 months.
Purpose: To evaluate topographic and tomographic changes in fellow eyes in unilateral keratoconus (KCN) patients by comparing them with normal eyes.
Design: Retrospective comparative case series.
Methods: Fourteen eyes of 14 patients with unilateral KCN and 34 eyes of 34 refractive surgery candidates were divided into 3 diagnostic groups using a Pentacam rotating Scheimpflug camera: advanced KCN eyes of unilateral KCN (KCN group, 14 eyes), normal fellow eyes of unilateral KCN (fellow eye group, 14 eyes), and refractive surgery candidates (normal group, 34 eyes).
Purpose: To investigate the incidence and severity of night vision disturbances after implantable collamer lens surgery and to analyze the risk factors.
Design: Retrospective, noncomparative study.
Methods: Medical charts from 50 eyes of 25 patients who underwent implantable collamer lens implantation were retrospectively reviewed.
Purpose: To compare visual outcomes and flap stability of LASIK with ultrathin 80- and 120-μm flaps created with a VisuMax femtosecond laser (Carl Zeiss Meditec, Jena, Germany) for moderate to high myopia and to evaluate the effect of corneal flap thickness on outcomes.
Methods: In a prospective contralateral eye study, 36 consecutive patients (72 eyes) underwent bilateral LASIK for myopia ranging from -2.00 to -10.
Purpose: To investigate the protective effect of rapamycin against alkali burn-induced corneal damage in mice.
Methods: BALB/c mice were treated with 0.1 N NaOH to the cornea for 30 seconds.
Background: To establish the consensus about the conditions for undertaking clinical trials in xenocorneal transplantation in Korea, specific issues regarding the xenocorneal transplantation on ethical and regulatory aspects are addressed, and the guidelines to conduct clinical trial of the xenocorneal transplantation are proposed.
Method And Results: Chapter 1 reviews the key ethical requirements and progress of a Korean regulatory framework for clinical trials of xenocorneal transplantation. Chapters 2-7 provide recommendations on source pigs, quality control of porcine corneal procurement, preclinical efficacy required to justify a clinical trial, strategies to prevent transmission of porcine endogenous retrovirus (PERV), patient selection for clinical trials, and informed consent in xenocorneal transplantation using either cellularized or decellularized porcine graft, which are essentially based on the International Xenotransplantation Association (IXA) islet xenotransplantation consensus statement.