Publications by authors named "Jeeyun Ahn"
Article Synopsis
- Parkinson's disease (PD) is a progressive movement disorder becoming more common due to an aging population, and researchers aimed to explore rare genetic variants that could help explain its development.
- Whole-exome sequencing was conducted on a large group of PD cases and controls of Asian ancestry, revealing significant links between the genes GBA1 and SMPD1 and the risk of developing PD, confirmed in additional samples.
- The research found that specific SMPD1 variants that reduced enzyme activity were particularly associated with PD risk, with a prominent Asian-specific variant being common among carriers.
Article Synopsis
- The study aimed to assess the real-world effectiveness of brolucizumab injections for patients with neovascular age-related macular degeneration (nAMD) who did not respond to previous treatments.
- Results showed that while visual acuity (BCVA) remained stable, anatomical improvements were noted, such as decreased central foveal thickness (CFT) and reduced presence of subretinal fluid (SRF) and pigment epithelial detachment (PED) after switching to brolucizumab.
- The safety profile was acceptable, with a low incidence of intraocular inflammation-related adverse events reported among the patients.
Prediction of Axial Length From Macular Optical Coherence Tomography Using Deep Learning Model.
Transl Vis Sci Technol
September 2024
Purpose: The purpose of this study was to develop a deep learning model for predicting the axial length (AL) of eyes using optical coherence tomography (OCT) images.
Methods: We retrospectively included patients with AL measurements and OCT images taken within 3 months. We utilized a 5-fold cross-validation with the ResNet-152 architecture, incorporating horizontal OCT images, vertical OCT images, and dual-input images.
In May 2023, the Committee of Clinical Practice Guidelines of the Korean Diabetes Association published the revised clinical practice guidelines for Korean adults with diabetes and prediabetes. We incorporated the latest clinical research findings through a comprehensive systematic literature review and applied them in a manner suitable for the Korean population. These guidelines are designed for all healthcare providers nationwide, including physicians, diabetes experts, and certified diabetes educators who manage patients with diabetes or individuals at risk of developing diabetes.
View Article and Find Full Text PDFArticle Synopsis
- * The research shows a significant genetic overlap between PCV and typical nAMD, with specific pathways related to collagen and fibrosis being more involved in PCV cases.
- * In-depth genetic analysis of PCV patients revealed rare variants in the COL1A1 gene and highlighted the role of GATA5 and related genes in processes like retinal angiogenesis and fibrosis, thus contributing to understanding AMD in the Asian demographic.
Parkinson's disease (PD) is a neurodegenerative disorder characterized by the aggregation of misfolded α-synuclein and progressive spreading of the aggregates from a few discrete regions to wider brain regions. Although PD has been classically considered a movement disorder, a large body of clinical evidence has revealed the progressive occurrence of non-motor symptoms. Patients present visual symptoms in the initial stages of the disease, and accumulation of phospho-α-synuclein, dopaminergic neuronal loss, and retinal thinning has been observed in the retinas of PD patients.
View Article and Find Full Text PDFBackground: To assess rhegmatogenous retinal detachment (RRD) surgery trends and training among young ophthalmologists (YOs, vitreoretinal fellows or attendings/consultants with ≤10 years of independent practice) and the impact of the COVID-19 pandemic.
Methods: An anonymous online survey was completed by 117 YOs in the Asia-Pacific regarding their RRD surgery experiences in 2021-2022.
Results: To achieve a 90% probability of surgical competency, 91 vitrectomy and 34 scleral buckling (SB) completions during fellowship were needed.
Purpose: To compare volumetric optical coherence tomography (OCT) biomarkers in bevacizumab responsive and bevacizumab refractory diabetic macular edema (DME) patients switched to the dexamethasone implant to ultimately identify possible prognostic indicators.
Methods: Retrospective analysis of DME patients treated with bevacizumab were done. Patients were divided into those who showed response to bevacizumab (bevacizumab only group) and others who were switched to the dexamethasone implant due to lack of response to bevacizumab (switching group).
Sequential structural and functional change in geographic atrophy on multimodal imaging in non-exudative age-related macular degeneration.
Graefes Arch Clin Exp Ophthalmol
August 2023
Purpose: To investigate the temporal order of photoreceptor atrophy, retinal pigment epithelium (RPE) atrophy and visual acuity loss in patients with center-involving geographic atrophy (GA) in non-exudative age-related macular degeneration (neAMD).
Methods: Forty eyes of 25 consecutive patients who eventually developed center-involving GA were investigated. Fundus autofluorescence (FAF) and infrared image coupled optical coherence tomography (OCT) were acquired at each visit.
Assessment of Risk Factors Affecting Refractive Outcomes after Phacovitrectomy for Epiretinal Membrane.
Korean J Ophthalmol
February 2023
Purpose: To investigate factors associated with refractive outcomes after phacovitrectomy for epiretinal membrane (ERM).
Methods: Retrospective review of patients undergoing phacovitrectomy for ERM was done. The main outcome measure was predictive refraction error (PE), defined as observed refraction error - target refraction error, calculated by the SRK/T, Haigis, and SRK II formulae.
Article Synopsis
- The study compares the clinical features, treatments, and outcomes between bullous variant central serous chorioretinopathy (bvCSC) and chronic nonbullous CSC.
- Patients with bvCSC were generally younger and more likely to have bilateral eye involvement compared to those with nonbullous CSC, and they received more systemic corticosteroids.
- Despite having worse vision at diagnosis, bvCSC patients showed a better response to treatment, leading to similar vision outcomes at follow-up.
Objectives: To investigate peripapillary retinal nerve fiber layer (pRNFL) changes in patients with progressive supranuclear palsy (PSP).
Methods: We included 21 PSP patients (36 eyes) who underwent peripapillary optical coherence tomography (OCT) scans at 2.5 ± 1.
Atypical Usher syndrome (USH) is poorly defined with a broad clinical spectrum. Here, we characterize the clinical phenotype of disease caused by variants in , and .Chart review evaluating demographic, clinical, imaging, and genetic findings of 19 patients from 18 families with a clinical diagnosis of retinal disease and confirmed disease-causing variants in , or .
View Article and Find Full Text PDFPurpose: The purpose of this study was to characterize the phenotypic spectrum of ophthalmic findings in patients with Alagille syndrome.
Methods: We conducted a retrospective, observational, multicenter, study on 46 eyes of 23 subjects with Alagille syndrome. We reviewed systemic and ophthalmologic data extracted from medical records, color fundus photography, fundus autofluorescence, optical coherence tomography, visual fields, electrophysiological assessments, and molecular genetic findings.
Purpose: To determine the mechanism of infection, clinical features, and risk factors of endophthalmitis after scleral fixation of an intraocular lens.
Methods: We included 15 patients with infectious endophthalmitis after scleral fixation of an intraocular lens between April 2004 and December 2017, as well as four patients found through a literature search. Thus, a total of 19 patients were analyzed.
Article Synopsis
- A study investigated the genetic factors that may make Japanese patients with type 2 diabetes more prone to diabetic retinopathy by analyzing over 5 million SNPs in a large sample of individuals.
- The research combined data from two genome-wide association studies (GWAS) and found significant associations with two specific genetic loci, STT3B and PALM2, which showed a strong connection to the disease.
- However, these findings were not confirmed in other populations like Koreans, Europeans, or African Americans, indicating the need for further research to validate these genetic associations.
Purpose: To investigate the efficacy of intravitreal bevacizumab injections (IVBs) for vitreous haemorrhage (VH) in proliferative diabetic retinopathy (PDR) with prior complete panretinal photocoagulation (PRP).
Methods: A multicentre cohort study of eyes with new VH in PDR after documented previous complete PRP was performed. Eyes were grouped according to IVB treatment at baseline, and cumulative rate of vitrectomy and spontaneous clear-up rate were compared as the main outcome.
Novel mutation in gene causing autosomal recessive progressive rod-cone dystrophy.
Ophthalmic Genet
August 2020
Background: Recent advances in genetic sequencing techniques have improved the overall diagnostic yield for finding genetic causes for inherited retinal dystrophies (IRD). Rod-cone dystrophy is the most common IRD and is characterized by the primary involvement of the rod photoreceptors. Over 80 causal genes have been identified so far giving clinicians insight into the pathogenesis.
View Article and Find Full Text PDFObjectives: To investigate the contrast sensitivity function in drug-naïve Parkinson's disease (PD) patients and its predictive value with longitudinal follow-up data.
Methods: We included newly diagnosed non-demented PD patients who performed contrast sensitivity test between 2013 and 2014. Contrast sensitivity function at drug-naïve state in PD patients was compared with age-matched normal control data of our center.