Trends and Barriers in Diabetic Retinopathy Screening: Korea National Health and Nutritional Examination Survey 2016-2021.

BACKGROUND: The prevalence of diabetes is increasing globally, highlighting the importance of preventive healthcare. This study aimed to identify the diabetic retinopathy (DR) screening rates and risk factors linked to DR screening nonadherence in the Korean population through a nationally representative sample survey. METHODS: Among the Korea National Health and Nutrition Examination Survey database from 2016 to 2021, participants aged ≥ 40 years with diabetes were included. The weighted estimate for nonadherence to DR screening within a year was calculated. Risk factor analyses were conducted using univariate and multivariate logistic regression. RESULTS: Among the 3,717 participants, 1,109 (29.5%) underwent DR screening within the past year, and this national estimate exhibited no statistically significant difference from 2016 to 2021 (P = 0.809). Nonadherence to annual DR screening was associated with residing in rural areas, age ≥ 80 years, low educational level, self-reported good health, absence of ocular disease, current smoking, lack of exercise and dietary diabetes treatment, and no activity limitation (all P < 0.05). CONCLUSION: The recent DR screening rate in Korea was relatively low. Factors associated with apathy and complacency towards personal health were associated with the nonadherence to DR screening. Educational interventions have the potential to enhance the annual screening rate for diabetic patients.

White matter microstructural integrity as a key to effective propagation of gamma entrainment in humans.

Gamma entrainment through sensory stimulation has the potential to reduce the pathology of Alzheimer's disease in mouse models. However, clinical trials in Alzheimer's disease (AD) patients have yielded inconsistent results, necessitating further investigation. This single-center pre-post intervention study aims to explore the influence of white matter microstructural integrity on gamma rhythm propagation from the visual cortex to AD-affected regions in 31 cognitively normal volunteers aged ≥ 65. Gamma rhythm propagation induced by optimal FLS was measured. Diffusion tensor imaging was employed to assess the integrity of white matter tracts of interest. After excluding 5 participants with a deficit in steady-state visually evoked potentials, 26 participants were included in the final analysis. In the linear regression analyses, gamma entrainment was identified as a significant predictor of gamma propagation (p < 0.001). Furthermore, the study identified white matter microstructural integrity as a significant predictor of gamma propagation by flickering light stimulation (p < 0.05), which was specific to tracts that connect occipital and temporal or frontal regions. These findings indicate that, despite robust entrainment of gamma rhythms in the visual cortex, their propagation to other regions may be impaired if the microstructural integrity of the white matter tracts connecting the visual cortex to other areas is compromised. Consequently, our findings have expanded our understanding of the prerequisites for effective gamma entrainment and suggest that future clinical trials utilizing visual stimulation for gamma entrainment should consider white matter tract microstructural integrity for candidate selection and outcome analysis.

Magnetically Controlled Intraocular Delivery of Dexamethasone Using Silica-Coated Magnetic Nanoparticles.

Although the number of patients with eye diseases is increasing, efficient drug delivery to the posterior segment of the eyeball remains challenging. The reasons include the unique anatomy of the eyeball, the blood-aqueous barrier, the blood-retina barrier, and drug elimination via the anterior chamber and uveoscleral routes. Solutions to these obstacles for therapeutic delivery to the posterior segment will increase the efficacy, efficiency, and safety of ophthalmic treatment. Micro/nanorobots are promising tools to deliver therapeutics to the retina under the direction of an external magnetic field. Although many groups have evaluated potential uses of micro/nanorobots in retinal treatment, most experiments have been performed under idealized in vitro laboratory conditions and thus do not fully demonstrate the clinical feasibility of this approach. This study examined the use of magnetic nanoparticles (MNPs) to deliver dexamethasone, a drug widely used in retinal disease treatment. The MNPs allowed sustainable drug release and successful magnetic manipulation inside bovine vitreous humor and the vitreous humor of living rabbits. Therefore, controlled drug distribution via magnetic manipulation of MNPs is a promising strategy for targeted drug delivery to the retina.

Organ-specific Toxocara canis larvae migration and host immune response in experimentally infected mice.

We investigated organ specific Toxocara canis larval migration in mice infected with T. canis larvae. We observed the worm burden and systemic immune responses. Three groups of BALB/c mice (n=5 each) were orally administered 1,000 T. canis 2nd stage larvae to induce larva migrans. Mice were sacrificed at 1, 3, and 5 weeks post-infection. Liver, lung, brain, and eye tissues were collected. Tissue from 2 mice per group was digested for larval count, while the remaining 3 mice underwent histological analysis. Blood hematology and serology were evaluated and compared to that in a control uninfected group (n=5) to assess the immune response. Cytokine levels in bronchoalveolar lavage (BAL) fluid were also analyzed. We found that, 1 week post-infection, the mean parasite load in the liver (72±7.1), brain (31±4.2), lungs (20±5.7), and eyes (2±0) peaked and stayed constant until the 3 weeks. By 5-week post-infection, the worm burden in the liver and lungs significantly decreased to 10±4.2 and 9±5.7, respectively, while they remained relatively stable in the brain and eyes (18±4.2 and 1±0, respectively). Interestingly, ocular larvae resided in all retinal layers, without notable inflammation in outer retina. Mice infected with T. canis exhibited elevated levels of neutrophils, monocytes, eosinophils, and immunoglobulin E. At 5 weeks post-infection, interleukin (IL)-5 and IL-13 levels were elevated in BAL fluid. Whereas IL-4, IL-10, IL-17, and interferon-γ levels in BAL fluid were similar to that in controls. Our findings demonstrate that a small portion of T. canis larvae migrate to the eyes and brain within the first week of infection. Minimal tissue inflammation was observed, probably due to increase of anti-inflammatory cytokines. This study contributes to our understanding of the histological and immunological responses to T. canis infection in mice, which may have implications to further understand human toxocariasis.

Association of baseline factors with 1-year outcomes in the SB11-ranibizumab equivalence trial: A post hoc analysis.

PURPOSE: To identify baseline factors associated with 1-year outcomes when treating neovascular age-related macular degeneration (nAMD) with ranibizumab biosimilar SB11 or reference ranibizumab (rRBZ), and to compare efficacy of the two products within subgroups judged to be clinically relevant. DESIGN: Post hoc analysis of a prospective, equivalence phase 3 randomized clinical trial (RCT) METHODS: 705 patients with nAMD were randomized 1:1 to receive SB11 or rRBZ for 48 weeks. Pooled and randomized groups were used to identify baseline factors associated with clinical outcomes at Week 52 using multiple linear regression models. Significant factors identified in regression analyses were confirmed in analyses of variance. Subgroup analyses comparing best-corrected visual acuity (BCVA) changes between SB11 and rRBZ were conducted. RESULTS: 634 (89.9%) participants completed the 52-week visit. Regression analyses showed that younger age, lower BCVA, and smaller total lesion area at baseline were associated with greater BCVA gain at Week 52, while older age, lower BCVA, and thicker central subfield thickness (CST) at baseline were predictors of greater CST reduction in the pooled group. Subgroup analyses demonstrated that BCVA outcomes appeared comparable for the SB11 and rRBZ groups. CONCLUSION: Post hoc analyses of the SB11-rRBZ equivalence study showed that baseline age, BCVA, CST, and total lesion area were prognostic factors for visual or anatomical outcomes of nAMD, while subgroup analyses demonstrated comparable results for SB11 and rRBZ. Collectively, the results appear comparable to similar RCTs of anti-vascular endothelial growth factor reference products for nAMD and strengthen confidence in the biosimilarity of SB11.

Long-term efficacy and safety of brolucizumab in neovascular age-related macular degeneration: A multicentre retrospective real-world study.

PURPOSE: To investigate the long-term efficacy and safety of intravitreal brolucizumab (BRZ) injections in patients with typical neovascular age-related macular degeneration (typical nAMD) and polypoidal choroidal vasculopathy (PCV). METHODS: This multicentre retrospective study included 401 eyes of 398 patients with nAMD who received BRZ injection(s), with a follow-up duration of ≥12 months. Changes in best-corrected visual acuity (BCVA), retinal fluid evaluation and central subfield thickness (CST) on optical coherence tomography were assessed. The efficacy of BRZ was compared between typical nAMD and PCV groups. RESULTS: Analyses were conducted with 280 eyes of 278 patients with typical nAMD and 121 eyes of 120 patients with PCV (mean age, 71.1 ± 8.6 years). 29 eyes (7.2%) were treatment naïve. The mean follow-up period was 15.3 ± 2.8 months; the mean number of BRZ injections within 1 year was 4.5 ± 1.7. BCVA was maintained during the follow-up period, and CST significantly improved from the first injection month and was maintained for 12 months in both the typical nAMD and PCV groups. The dry macula proportion increased from 2.7% at baseline to 56.1% at 1 month and 42.9% at 12 months. Among the 18 eyes that underwent indocyanine green angiography both before and after treatment, 10 (55.6%) showed polyp regression. Overall, the incidence of intraocular inflammation (IOI), retinal vasculitis and occlusive retinal vasculitis was 9.4% (38 eyes), 1.2% (5 eyes) and 0.5% (2 eyes), respectively. IOI occurred from the first to the sixth injections, with an average IOI onset of 28.5 ± 1.4 days. All eyes achieved IOI resolution, although the two eyes with occlusive retinal vasculitis showed a severe visual decline after IOI resolution. CONCLUSION: Brolucizumab was effective in maintaining BCVA and managing fluid in eyes with nAMD for up to 1 year, exhibiting a high polyp regression rate. However, the not uncommon incidence of IOI and the severe visual decline caused by the rare occlusive retinal vasculitis following BRZ treatment underscore the importance of careful monitoring and timely management.

Clinical characteristics of recurrent non-arteritic retinal artery occlusion.

OBJECTIVES: To investigate the recurrent non-arteritic retinal artery occlusion (RAO) in the same or opposite eye. METHODS: We searched the RAO registry at Seoul National University Bundang Hospital and included patients with recurrent RAO in the present study. Ophthalmic and systemic features were analysed to identify risk factors and visual outcomes. RESULTS: Of the 850 patients in the non-arteritic RAO cohort, 11 (1.3%) experienced a second RAO recurrence, either in the same (5 patients; 0.6%) or opposite (6 patients; 0.7%) eye. The same eye group experienced an earlier recurrence (1-2 months, median 1 month) than the opposite eye group, where the time to recurrence was notably longer (8-66 months, median 22 months). Best corrected visual acuity (BCVA) in the same eye group decreased after the recurrence of RAO. In the same eye group, initial BCVA ranged from 20/200 to counting fingers (CF), while BCVA during RAO recurrence ranged from CF to hand motion. When RAO recurred in the opposite eye, the reduction in visual acuity was less severe than the reduction of the initial episode: initial episode ranged from 20/400 to light perception and recurrent episode ranged from 20/25 to 20/400. Patients exhibited varying degrees of carotid (81.8%) and cerebral (9.1%) artery occlusions. Additionally, one patient in each group (total 2 patients, 18.2%) experienced a stroke 6 months after RAO recurrence. CONCLUSIONS: Since the RAO recurrences could lead to devastating visual impairment, it is essential to emphasise the importance of risk factor screening to patients while collaborating with neurologists and cardiologists.

Two novel non-coding single nucleotide variants in the DNase1 hypersensitivity site of PRDM13 causing North Carolina macular dystrophy in Korea.

Purpose: Pathogenic variants in North Carolina macular dystrophy (NCMD) have rarely been reported in the East Asian population. Herein, we reported novel variants of NCMD in 2 Korean families. Methods: The regions associated with NCMD were analyzed with genome sequencing, and variants were filtered based on the minor allele frequency (0.5%) and heterozygosity. Non-coding variants were functionally annotated using multiple computational tools. Results: We identified two rare novel variants, chr6:g.99,598,914T>C (hg38; V17) and chr6:g.99,598,926G>A (hg38; V18) upstream of PRDM13 in families A and B, respectively. In Family 1, Grade 2 NCMD and a best-corrected visual acuity of 20/25 and 20/200 in the right and left eyes, respectively, were observed. In Family B, all affected individuals had Grade 1 NCMD with characteristic confluent drusen at the fovea and a best-corrected visual acuity of 20/20 in both eyes. These two variants are 10-22 bp downstream of the reported V10 variant within the DNase1 hypersensitivity site. This site is associated with progressive bifocal chorioretinal atrophy and congenital posterior polar chorioretinal hypertrophy and lies in the putative enhancer site of PRDM13. Conclusion: We identified two novel NCMD variants in the Korean population and further validated the regulatory role of the DNase1 hypersensitivity site upstream of PRDM13.

Changes in intraocular pressure following intravitreal dexamethasone implant in patients with history of glaucoma filtration surgery.

PURPOSE: This study aimed to evaluate changes in intraocular pressure following intravitreal dexamethasone implant injection, specifically in patients undergoing glaucoma filtration surgery. METHODS: The degree of increase in intraocular pressure was compared retrospectively among three groups. Group 1 comprised patients who underwent prior glaucoma filtration surgery (54 eyes). Group 2 included patients with or suspected glaucoma without such surgical history (20 eyes). Group 3 included patients without glaucoma (33 eyes). Pressure measurements were taken before the injection and at 1, 2, 3, and 6 months post-injection. A subgroup analysis was performed for pressure > 35 mmHg, > 30 mmHg, > 25 mmHg, and a difference > 10 mmHg between the peak and baseline pressure. RESULTS: Group 1 consistently displayed lower pressures compared with Group 2, with significant difference at both 1- and 6-month post-injections (15.09 mmHg vs. 18.10 mmHg, P = 0.042 and 13.91 mg vs. 17.25 mmHg, P = 0.040). The proportion of patients in Group 1 and Group 3 with pressures > 25 mmHg, > 30 mmHg, and a difference > 10 mmHg did not significantly differ (15.6% vs. 9.5%, P = 0.231; 3.1% vs. 2.3%, P = 0.867; and 17.1% vs. 7.1%, P = 0.231). Notably, Group 2 exhibited a significantly higher proportion within each category (> 25 mmHg, 24.0%; > 30 mmHg, 20.0%; > 10 mmHg difference, 28.0%). CONCLUSION: Intravitreal dexamethasone implant did not increase the risk of elevated intraocular pressure in patients with a history of glaucoma filtration surgery compared with patients with suspected glaucoma; the risk was similar to those without glaucoma.

Immunogenicity and Potential for Intraocular Inflammation of Intravitreal Anti-VEGF Drugs.

Background: Concerns of intraocular inflammation associated with intravitreal administration of anti-VEGF drugs have been risen and the exact mechanism is not yet elucidated. Objective: To explore the relationship between immunogenicity and intraocular inflammation in intravitreal anti-VEGF drugs. Methods: This review examines the immunogenicity of individual intravitreal anti-VEGF drugs and their potential link to intraocular inflammation. Results: We suggest that the main cause of intraocular inflammation is the presence of pre-existing and treatment-induced antidrug antibodies, along with considerations related to the molecular structure, which includes the drug's format and size. Conclusions: Researchers and clinicians involved in the advancement of new anti-VEGF drugs should take into consideration the factors related to intraocular inflammation that have been discussed.

Nationwide incidence of congenital and infantile cataract requiring surgery in Korea.

Congenital and infantile (CI) cataract is one of the most important and preventable cause of blindness in children, but the incidence has not been studied in Korea. We collected data from the national claims database of the National Health Insurance Service of Korea from 2002 through 2019. We identified children who underwent cataract surgery within the age of 5 years, and cumulative incidence rates were calculated for each of the three age criteria. 989 patients out of 4,221,459 births underwent surgery with CI cataract during the period. The cumulative incidence rates per 10,000 births were 1.60 (0-1 years), 2.38 (0-3 years), and 2.95 (0-5 years), respectively. The incidence peaked in the 2007 birth cohort, which coincides with the start of the national screening program for infants/children. Primary intraocular lens implantation was performed in 439 patients (44%). Strabismus and glaucoma requiring surgery occurred in 291 patients (29.4%) and 32 patients (3.2%), respectively, within 8 years after cataract surgery. The incidence rates of CI cataract in Korea appear to be comparable to previous studies in other regions. The early screening program for infants may reduce delayed diagnosis and increase the proportion of patients undergoing surgery at a critical time for visual development.

Scleral buckling with adjuvant pneumatic retinopexy versus scleral buckling alone for rhegmatogenous retinal detachment.

To compare the efficacy of scleral buckling with adjuvant pneumatic retinopexy (SB with PR) and scleral buckling (SB) alone for primary rhegmatogenous retinal detachment (RRD). This retrospective and comparative study included patients who underwent SB with PR (n = 88) or SB alone (n = 161) for primary RRD. The primary anatomical success rate for SB with PR was 81.8%, whereas that for SB alone was 80.7% (P = 0.836). Among patients who achieved primary anatomical success, those in the SB with PR group showed postoperative epiretinal membrane (ERM) formation more frequently than those in the SB alone group (11 of 72 [15.3%] vs. 6 of 130 [4.6%]) (P = 0.009). The mean time to subretinal fluid absorption was not significantly different between the SB with PR and SB alone groups (11.2 ± 6.2 vs. 11.4 ± 5.8 months, P = 0.881). In the SB with PR group, retinal detachment involving ≥ three quadrants was a significant risk factor for surgical failure (hazard ratio, 3.04; P = 0.041). Adjuvant pneumatic retinopexy does not provide additional benefit in improving the surgical outcomes of SB for primary RRD repair.

Biosimilars of anti-vascular endothelial growth factor for ophthalmic diseases: A review.

The development of intravitreally injected biologic medicines (biologics) acting against vascular endothelial growth factor (VEGF) substantially improved the clinical outcomes of patients with common VEGF-driven retinal diseases. The relatively high cost of branded agents, however, represents a financial burden for most healthcare systems and patients, likely resulting in impaired access to treatment and poorer clinical outcomes for some patients. Biosimilar medicines (biosimilars) are clinically equivalent, potentially economic alternatives to reference products. Biosimilars approved by leading health authorities have been demonstrated to be similar to the reference product in a comprehensive comparability exercise, generating the totality of evidence necessary to support analytical, pre-clinical, and clinical biosimilarity. Anti-VEGF biosimilars have been entering the field of ophthalmology in the US since 2022. We review regulatory and scientific concepts of biosimilars, the biosimilar development landscape in ophthalmology, with a specific focus on anti-VEGF biosimilars, and discuss opportunities and challenges facing the uptake of biosimilars.

Efficacy and Safety of Switching from Adalimumab Originator to SB5, Adalimumab Biosimilar for Noninfectious Uveitis.

PURPOSE: To evaluate the efficacy and safety of switching from adalimumab originator (Humira, AbbVie) to SB5, adalimumab biosimilar (Adalloce, Samsung Bioepis) in patients with noninfectious uveitis (NIU). METHODS: Fifteen patients (29 eyes) with NIU who were switched from adalimumab originator to SB5 and followed up for 6 months or longer were retrospectively included. Data consisted of best-corrected visual acuity (BCVA, logMAR), intraocular pressure (IOP, mmHg), anterior chamber (AC) cell grade, anterior vitreous (AV) cell grade, vitreous haze grade, central macular thickness (CMT, µm), and macular volume (MV, mm3) at pre-switching, 2, 4, and 6 months post-switching. RESULTS: There were no significant differences in BCVA, AC and AV cell grades, and vitreous haze grades at 2, 4, and 6 months post- compared with pre-switching, and no significant differences in CMT and MV at 2 and 6 months post-switching. CMT and MV decreased from 260.55 ± 67.44 µm and 8.37 ± 1.14 mm3 at pre-switching to 244.14 ± 60.31 µm (p = 0.032) and 8.11 ± 1.20 mm3 (p = 0.027) at 4 months post-switching, respectively. There was no recurrence of uveitis, as defined by AC cell grade, vitreous haze, or BCVA. Four patients (27%) were switched back to adalimumab originator after a mean of 9 weeks, due to discomfort during the injection (three patients) and technical difficulty with the new injection device (one patient). No other adverse events occurred after switching to SB5. CONCLUSION: Switching from adalimumab originator to SB5 for NIU does not result in clinically significant differences in treatment efficacy and safety.

Distinct Clinical Effects of Two RP1L1 Hotspots in East Asian Patients With Occult Macular Dystrophy (Miyake Disease): EAOMD Report 4.

Purpose: To characterize the clinical effects of two RP1L1 hotspots in patients with East Asian occult macular dystrophy (OMD). Methods: Fifty-one patients diagnosed with OMD harboring monoallelic pathogenic RP1L1 variants (Miyake disease) from Japan, South Korea, and China were enrolled. Patients were classified into two genotype groups: group A, p.R45W, and group B, missense variants located between amino acids (aa) 1196 and 1201. The clinical parameters of the two genotypes were compared, and deep learning based on spectral-domain optical coherence tomographic (SD-OCT) images was used to distinguish the morphologic differences. Results: Groups A and B included 29 and 22 patients, respectively. The median age of onset in groups A and B was 14.0 and 40.0 years, respectively. The median logMAR visual acuity of groups A and B was 0.70 and 0.51, respectively, and the survival curve analysis revealed a 15-year difference in vision loss (logMAR 0.22). A statistically significant difference was observed in the visual field classification, but no significant difference was found in the multifocal electroretinographic classification. High accuracy (75.4%) was achieved in classifying genotype groups based on SD-OCT images using machine learning. Conclusions: Distinct clinical severities and morphologic phenotypes supported by artificial intelligence-based classification were derived from the two investigated RP1L1 hotspots: a more severe phenotype (p.R45W) and a milder phenotype (1196-1201 aa). This newly identified genotype-phenotype association will be valuable for medical care and the design of therapeutic trials.

ADDITIONAL PNEUMATIC RETINOPEXY IN PATIENTS WITH PERSISTENT RETINAL DETACHMENT AFTER SCLERAL BUCKLING.

PURPOSE: To investigate the efficacy, safety, and indications for additional pneumatic retinopexy (PR) in patients with persistent retinal detachment after scleral buckling. METHODS: This retrospective study included patients who underwent additional PR after scleral buckling for primary rhegmatogenous retinal detachment (n = 78). We defined "inadequate buckle" as retinal detachment persistence because of low buckle height despite accurate buckle placement and "buckle misplacement" as an uncovered tear because of incorrect buckle placement. RESULTS: The anatomical success rate after additional PR was 52.6%. Development of proliferative vitreoretinopathy Grade B (hazard ratio, 5.73; P < 0.001) and inferior retinal tears (hazard ratio, 2.12; P = 0.040) were significant risk factors for anatomical failure. The most common cause of anatomical failure was proliferative vitreoretinopathy (19 of 37; 51.4%), and epiretinal membrane formation was a common complication after additional PR (22 of 78; 28.2%). The anatomical success rate with additional PR was significantly higher in the inadequate buckle group than in the misplacement group (8 of 9 [88.9%] vs. 1228 [42.9%]; P = 0.023). CONCLUSION: Development of proliferative vitreoretinopathy Grade B and inferior retinal tears were significantly associated with anatomical failure after additional PR. Additional PR may benefit patients with superior retinal tears or low buckle height and those without proliferative vitreoretinopathy.

Rationale and protocol paper for the Asia Pacific Network for inherited eye diseases.

PURPOSE: There are major gaps in our knowledge of hereditary ocular conditions in the Asia-Pacific population, which comprises approximately 60% of the world's population. Therefore, a concerted regional effort is urgently needed to close this critical knowledge gap and apply precision medicine technology to improve the quality of lives of these patients in the Asia-Pacific region. DESIGN: Multi-national, multi-center collaborative network. METHODS: The Research Standing Committee of the Asia-Pacific Academy of Ophthalmology and the Asia-Pacific Society of Eye Genetics fostered this research collaboration, which brings together renowned institutions and experts for inherited eye diseases in the Asia-Pacific region. The immediate priority of the network will be inherited retinal diseases (IRDs), where there is a lack of detailed characterization of these conditions and in the number of established registries. RESULTS: The network comprises 55 members from 35 centers, spanning 12 countries and regions, including Australia, China, India, Indonesia, Japan, South Korea, Malaysia, Nepal, Philippines, Singapore, Taiwan, and Thailand. The steering committee comprises ophthalmologists with experience in consortia for eye diseases in the Asia-Pacific region, leading ophthalmologists and vision scientists in the field of IRDs internationally, and ophthalmic geneticists. CONCLUSIONS: The Asia Pacific Inherited Eye Disease (APIED) network aims to (1) improve genotyping capabilities and expertise to increase early and accurate genetic diagnosis of IRDs, (2) harmonise deep phenotyping practices and utilization of ontological terms, and (3) establish high-quality, multi-user, federated disease registries that will facilitate patient care, genetic counseling, and research of IRDs regionally and internationally.

Phenotypic and Genetic Alterations in Adult-Onset Cone and Cone-Rod Dystrophy.

INTRODUCTION: The objective of this study was to investigate the clinical characteristics and genetic spectrum of adult-onset cone/cone-rod dystrophy (AOCD/AOCRD) in Korean individuals. METHODS: This is a single-center, retrospective cross-sectional study. We analyzed 22 individuals with genetically confirmed cone dystrophy, with symptoms beginning after 30 years of age. All patients underwent comprehensive ophthalmic and electrophysiological examinations. Exome sequencing of 296 genes associated with inherited retinal disease was performed. The clinical features of patients with AOCD/AOCRD and the causative genes and variants detected by exome sequencing were analyzed. RESULTS: The median age at the first visit was 52 years (range, 31-76 years), and the most common initial symptom was reduced visual acuity. In most cases, fundus photography showed a bull's eye pattern with foveal sparing, consistent with perifoveal photoreceptor loss on optical coherence tomography. We identified disease-causing variants in six genes: RP1, CRX, CDHR1, PROM1, CRB1, and GUCY2D. Pathogenic variants in RP1, CRX, and CDHR1 were identified in 77% of the AOCD/AOCRD cases, including p.Cys1399LeufsTer5, p.Arg1933Ter, and p.Ile2061SerfsTer12 in RP1; p.Ter300GlnextTer118 in CRX; and p.Glu201Lys in CDHR1. No characteristic imaging differences were observed for any of the causative genes. Most of the RP1-related AOCD/AOCRD cases showed a decreased amplitude only in the photopic electroretinogram (ERG), whereas CRX-related AOCD/AOCRD cases showed a slightly decreased amplitude in both the scotopic and photopic ERGs. CONCLUSION: In case of visual impairment with bull's eye pattern of RPE atrophy recognized after the middle age, a comprehensive ophthalmic examination and genetic test should be considered, with the possibility of AOCD/AOCRD in East Asians.

Comparison of posterior capsule rupture rates during phacoemulsification using 3D heads-up visualization system and traditional microscopes.

PURPOSE: To compare the posterior capsule rupture (PCR) rates of cataract surgery using a traditional ophthalmic surgical microscope (OSM) and a 3D heads-up visualization system (HUVS). SETTING: Single tertiary referral center. DESIGN: Retrospective study. METHODS: This study included 10 101 eyes that underwent phacoemulsification cataract surgery. Surgeries were performed using either 3D HUVS (1964 eyes, performed by 2 surgeons, HUVS group) or traditional OSM (8137 eyes, performed by 6 surgeons, OSM group) from February 2018 to June 2022. Data were collected based on the diagnosis-related group system, and the rate of PCR requiring vitrectomy and the surgical time were evaluated. RESULTS: The PCR rates were not significantly different between the OSM (n = 63; 0.7%) and HUVS (n = 19; 0.9%, P = .392) groups. The mean surgical time was significantly longer in the HUVS group (14.7 ± 10.6 minutes) than in the OSM group (12.9 ± 9.9 minutes, P < .001). In the 3D HUVS group, there were no PCR cases among the initial 100 patients. In both groups, no significant difference was observed in the PCR rates over time. Although the difference was not statistically significant, the PCR rate decreased over time in the HUVS group. CONCLUSIONS: The results indicate that 3D HUVS-based cataract surgery performed by experienced cataract surgeons had a PCR rate similar to that of traditional OSM-based surgery during the 4-year study period. Although the surgical time was slightly longer with 3D HUVS, cataract surgery using 3D HUVS can be performed safely by experienced surgeons.

Whole genome sequencing for inherited retinal diseases in the Korean National Project of Bio Big Data.

PURPOSE: This study aimed to analyze the genetic results of inherited retinal diseases (IRDs) and evaluate the diagnostic usefulness of whole genome sequencing (WGS) in the Korean National Project of Bio Big Data. METHODS: As part of the Korean National Project of Bio Big Data, WGS was performed on 32 individuals with IRDs with no identified pathogenic variants through whole or targeted exome sequencing. RESULTS: Individuals with retinitis pigmentosa (n = 23), cone dystrophy (n = 2), cone-rod dystrophy (n = 2), familial exudative vitreoretinopathy (n = 2), pigmented paravenous chorioretinal atrophy (n = 1), North Carolina macular dystrophy (n = 1), and bull's-eye macular dystrophy (n = 1) were included. WGS revealed genetic mutations in the IQCB1, PRPF31, USH2A, and GUCY2D genes in five cases (15.6%). Two large structural variations and an intronic variant were newly detected in three cases. Two individuals had biallelic missense mutations that were not identified in previous exome sequencing. CONCLUSION: With WGS, the causative variants in 15.6% of unsolved IRDs from the Korean National Project of Bio Big Data were identified. Further research with a larger cohort might unveil the diagnostic usefulness of WGS in IRDs and other diseases.