Choroidal venous overload in Vogt‒Koyanagi‒Harada disease.

BACKGROUND/OBJECTIVES: This study aimed to investigate the change of choroidal venous overload in Vogt‒Koyanagi‒Harada (VKH) disease. Clinical records of 52 patients with VKH disease (52 eyes) and 24 control subjects (24 eyes) who underwent multimodal imaging, including fluorescein angiography (FA) and indocyanine green angiography (ICGA), were retrospectively reviewed. SUBJECTS/METHODS: Imaging data were assessed for signs associated with choroidal venous overload, e.g., choroidal perfusion delay, choroidal vascular hyperpermeability, dilated choroidal veins, and intervortex venous anastomosis (IVA). Dual FA and ICGA scoring for active posterior segment inflammation was performed. Clinical and imaging features associated with choroidal venous overload were compared between early- and late-stage VKH disease. RESULTS: Choroidal perfusion delay, choroidal vascular hyperpermeability, dilated choroidal veins, and IVA were more prevalent in eyes with VKH disease (69.2%, 67.3%, 61.5%, and 65.4%, respectively) than in control eyes (25.0%, 20.8%, 25.0%, and 37.5%, respectively) (p < 0.05). All eyes with IVA in the early-stage of VKH disease had got other 3 signs. All choroidal venous overload signs were more prevalent in patients with early-stage (20 eyes) than in those with late-stage VKH disease (32 eyes) (p < 0.05). The number of choroidal venous overload signs were inversely related to disease duration (p < 0.001) and proportionally related to the total ICGA score (p < 0.001). IVA was significantly associated with the total ICGA score in logistic regression (p = 0.014). CONCLUSIONS: Choroidal venous overload occurs early in VKH disease. Angiographic signs of choroidal venous overload may be useful markers to assess the status of VKH disease.

Advanced age-related macular degeneration and risk factors in eyes with pachydrusen.

The risk of progression to advanced age-related macular degeneration (AMD) varies depending on the type of drusen. This retrospective longitudinal study included 248 eyes of 156 patients with pachydrusen without advanced AMD at baseline. Macular neovascularization (MNV) and geographic atrophy (GA) were evaluated. Risk factors for progression to advanced AMD were determined using multivariate Cox regression analysis. The mean age at baseline was 65.4 ± 9.1 years, and the mean follow-up duration was 6.40 ± 3.58 years. The mean total number of pachydrusen and macular pachydrusen were 4.10 ± 2.85 and 2.27 ± 1.81 per eye, respectively. Pachydrusen was accompanied by other types of drusen in 4.8% (12 eyes) of eyes at baseline. During follow-up, MNVs occurred in 2.8% (seven eyes), including polypoidal choroidal vasculopathy (PCV six eyes); however, no GA occurred. Regarding risk factors for progression to neovascular AMD, age (p = 0.023) and macular pigmentary changes (p = 0.014) were significantly associated with MNV development. The cumulative incidence of MNV was significantly higher in the group with macular pigmentary changes (17.39% vs. 0.57% at 10 years; p = 0.0005). The number of macular pachydrusen and the presence of MNV in the fellow eye did not show a statistically significant relationship with MNV development. Age and macular pigmentary changes are risk factors for MNV development in the eyes with pachydrusen. Eyes with pachydrusen appear to have a risk profile for advanced AMD that is different from that of AMD eyes with drusen or drusenoid deposits other than pachydrusen.

Enhancing foveal avascular zone analysis for Alzheimer's diagnosis with AI segmentation and machine learning using multiple radiomic features.

We propose a hybrid technique that employs artificial intelligence (AI)-based segmentation and machine learning classification using multiple features extracted from the foveal avascular zone (FAZ)-a retinal biomarker for Alzheimer's disease-to improve the disease diagnostic performance. Imaging data of optical coherence tomography angiography from 37 patients with Alzheimer's disease and 48 healthy controls were investigated. The presence or absence of brain amyloids was confirmed using amyloid positron emission tomography. In the superficial capillary plexus of the angiography scans, the FAZ was automatically segmented using an AI method to extract multiple biomarkers (area, solidity, compactness, roundness, and eccentricity), which were paired with clinical data (age and sex) as common correction variables. We used a light-gradient boosting machine (a light-gradient boosting machine is a machine learning algorithm based on trees utilizing gradient boosting) to diagnose Alzheimer's disease by integrating the corresponding multiple radiomic biomarkers. Fivefold cross-validation was applied for analysis, and the diagnostic performance for Alzheimer's disease was determined by the area under the curve. The proposed hybrid technique achieved an area under the curve of [Formula: see text]%, outperforming the existing single-feature (area) criteria by over 13%. Furthermore, in the holdout test set, the proposed technique exhibited a 14% improvement compared to single features, achieving an area under the curve of 72.0± 4.8%. Based on these facts, we have demonstrated the effectiveness of our technology in achieving significant performance improvements in FAZ-based Alzheimer's diagnosis research through the use of multiple radiomic biomarkers (area, solidity, compactness, roundness, and eccentricity).

The risk of fracture in age-related macular degeneration according to the presence of visual disability: a nationwide cohort study.

PURPOSE: To evaluate the association between age-related macular degeneration (AMD) with or without visual disability (VD) and the risk of fracture using the National Health Insurance data in South Korea. METHODS: In total, 3,894,702 individuals who had taken part in health-screening programs between January 1, 2009, and December 31, 2009, were included in the cohort and followed until December 31, 2019. The participants with VD, which could be related to the severity of AMD, were defined as those with a loss of vision or visual field defect as certified by the Korean government's Ministry of Health and Welfare. The hazard ratio was calculated for groups (control and AMD with/without VD) using the multivariable-adjusted cox regression analysis. RESULTS: In total, 466,890 participants (11.99%) were diagnosed with fractures during the study period. An increased risk of fracture was observed in individuals with AMD compared with the control (adjusted hazard ratio (aHR), 1.09, 95% confidence interval (CI), 1.06-1.11). Furthermore, among the AMD individuals, an increased risk of fracture was prominent in individuals with VD (aHR 1.17, 95% CI 1.08-1.27) than those without VD (aHR 1.08, 95% CI 1.06-1.11) compared with the reference group (control). CONCLUSIONS: AMD was associated with an increased risk of fracture even without VD. Prevention for fracture should be considered in AMD patients, especially when accompanied by VD.

Macular lesions associated with age-related macular degeneration in pachydrusen eyes.

BACKGROUND: To investigate the prevalence of macular lesions associated with age-related macular degeneration (AMD) in eyes with pachydrusen. METHODS: Clinical records and multimodal imaging data of patients over 50 years old with drusen or drusenoid deposits were retrospectively assessed, and eyes with pachydrusen were included in this study. The presence of AMD features, including drusen or drusenoid deposits, macular pigmentary abnormalities, geographic atrophy (GA), and macular neovascularization (MNV), were evaluated. RESULTS: Out of 967 eyes of 494 patients with drusen or drusenoid deposits, 330 eyes of 183 patients had pachydrusen (34.1%). The mean age was 66.1 ± 9.3 years, and the subfoveal choroidal thickness (SFCT) was 292.7 ± 100.1 µm. The mean number of pachydrusen per eye was 2.22 ± 1.73. The majority of eyes with pachydrusen had no other drusen or drusenoid deposits (95.2%). Only 16 eyes (4.8%) had other deposits, including soft drusen (10 eyes, 3.0%), cuticular drusen (3 eyes, 0.9%), and reticular pseudodrusen (RPD; 3 eyes, 0.9%). Macular pigmentary abnormalities accompanied pachydrusen in 68 eyes (27.4%). None of the eyes had GA, and 82 eyes (24.8%) had MNV. The majority of MNV was polypoidal choroidal vasculopathy (PCV; 65 eyes, 19.7%), followed by type 1 (10 eyes, 3.0%), type 2 (5 eyes, 1.5%), and type 3 MNV (2 eyes, 0.6%). CONCLUSIONS: Eyes with pachydrusen in Korean population have several characteristic AMD lesions in low frequencies. These findings indicate that pachydrusen might have diagnostic and prognostic values that are different from those of other drusen or drusenoid deposits.

Microperimetric evaluation for different methods of epiretinal membrane surgery.

PURPOSE: To investigate the anatomic and functional outcomes using microperimetry for the surgical methods for idiopathic epiretinal membranes (ERM). METHODS: This retrospective study included 41 eyes from 41 patients. All patients underwent combined epiretinal membrane and cataract surgery. Best-corrected visual acuity (BCVA), optical coherence tomography, and microperimetry were performed before and 6 months and 1 year after surgery. The patients were divided into 3 groups; "ERM removal only without indocyanine green (ICG) staining", "ERM and internal limiting membrane (ILM) removal without ICG staining", and "ERM and ILM removal with ICG staining". RESULTS: Preoperatively, the ages, BCVAs, central macular thickness (CMT), and mean retinal sensitivities of central 6° (MRSs) of the groups were not significantly different (p > 0.05). Postoperatively, the MRSs of the "ERM removal only without ICG staining" and "ERM and ILM removal without ICG staining" groups were not significantly different (p > 0.05). The MRSs of the "ERM and ILM removal without ICG staining" and "ERM and ILM removal with ICG staining" groups were not significantly different (p > 0.05). However, the MRSs of the "ERM and ILM removal with ICG staining" group significantly reduced than "ERM removal only without ICG staining" group (p < 0.05). CONCLUSION: This retrospective study found reduced retinal sensitivity in ERM and ILM removal with ICG staining group compared to ERM removal only without ICG staining. Further studies with larger sample sizes are required.

Increased risk of Parkinson's disease amongst patients with age-related macular degeneration and visual disability: A nationwide cohort study.

BACKGROUND AND PURPOSE: The association between Parkinson's disease (PD) and age-related macular degeneration (AMD) has been shown in previous reports. However, the association between the severity of AMD and PD development is unknown. The aim was to evaluate the association of AMD with/without visual disability (VD) with the risk of PD occurrence using the National Health Insurance data in South Korea. METHODS: A total of 4,205,520 individuals, 50 years or older and without a previous diagnosis of PD, participated in the Korean National Health Screening Program in 2009. AMD was verified using diagnostic codes, and participants with VD were defined as those with loss of vision or visual field defect as certified by the Korean Government. The participants were followed up until 31 December 2019, and incident cases of PD were identified using registered diagnostic codes. The hazard ratio was calculated for groups (control and AMD with/without VD) using multivariable adjusted Cox regression analysis. RESULTS: In total, 37,507 participants (0.89%) were diagnosed with PD. Amongst individuals with AMD, the risk of PD development was higher in individuals with VD (adjusted hazard ratio [aHR] 1.35, 95% confidence interval [CI] 1.09-1.67) than in those without (aHR 1.22, 95% CI 1.15-1.30) compared with controls. Additionally, an increased risk of PD was observed in individuals with AMD compared with controls, regardless of the presence of VD (aHR 1.23, 95% CI 1.16-1.31). CONCLUSIONS: Visual disability in AMD was associated with the development of PD. This suggests that neurodegeneration in PD and AMD may have common pathways.

Response to brolucizumab treatment for refractory serous pigment epithelial detachment secondary to polypoidal choroidal vasculopathy.

PURPOSE: To report the efficacy and safety of brolucizumab in the treatment of refractory serous pigment epithelial detachment (PED) secondary to polypoidal choroidal vasculopathy (PCV). METHODS: Twenty-six eyes of 26 patients were included. Intravitreal brolucizumab 6.0 mg was administered, followed by pro re nata (PRN) retreatment at monthly follow-ups. All patients underwent spectralis domain optical coherence tomography (SD-OCT), fluorescein angiography, and indocyanine green angiography before the first brolucizumab injection. SD-OCT was repeated at follow-up visits. The height and width of the serous PEDs, measured using SD-OCT, were analyzed. RESULTS: The number of previous anti-VEGF injections was 12.3 ± 15.0. During brolucizumab treatment, anatomical improvement was achieved and maintained in the height and width of the PEDs (p < 0.05). However, the visual outcome did not improve significantly (p > 0.05). A good response was achieved in 69.2% of eyes at 1 month and at the last visit. Relapse and complete resolution were observed in 27.8 and 23.1% of patients, respectively. The number of brolucizumab injections was 2.00 ± 0.85. Intraocular inflammation, vascular obstruction, and retinal pigment epithelial tears were not observed. CONCLUSION: Intravitreal brolucizumab may be an effective and safe treatment option for refractory serous PEDs in patients with PCV.

Longitudinal change of reticular pseudodrusen area in ultrawide-field imaging.

This study aimed to investigate the longitudinal change in the reticular pseudodrusen (RPD) area in the fundus and its association with late age-related macular degeneration (AMD). 91 RPD eyes (55 patients; age 67.9 ± 7.3 years) with > 5 years' follow-up (6.8 ± 0.9 years) from a single medical center were enrolled. Ultrawide-field photography images were analyzed using the concentric rings method, and the RPD area was semi-quantitatively classified according to the affected segment number into central, intermediate, and extensive types. Correlations of longitudinal changes in the RPD area and late AMD risk were investigated. RPD area increased significantly during the follow-up (p < 0.001). The increase rate correlated with age (r = 0.207; p = 0.048), RPD area at first visit (r = - 0.222; p = 0.035), and the decrease rate of subfoveal choroidal thickness (SFCT) (r = 0.217; p = 0.039). Many central (18/49, 36.7%) and intermediate (15/23, 65.2%) types switched to the more advanced type during the follow-up. Macular neovascularization and geographic atrophy developed in 12.3% and 18.7% of patients by 7 years. Late AMD incidence was significantly higher in eyes with large than in those with small RPD areas (p = 0.002). Larger RPD area at baseline, faster increase in RPD area, thinner SFCT, rapid decrease in SFCT, and the presence of late AMD on fellow eye were associated with late AMD. All RPD areas progressively increase over time. The regular assessment of RPD area may help to predict late AMD risk in RPD eyes.

Evaluation of the microperimetry in eyes with cuticular drusen.

Retinal sensitivity may vary by subtypes of cuticular drusen. This retrospective study included 52 eyes of 32 patients with cuticular drusen. All the patients underwent assessment of best-corrected visual acuity (BCVA), spectral-domain optical coherence tomography (SD-OCT), color fundus photography, fluorescein angiography, fundus autofluorescence, and microperimetry. The area occupied by drusen was counted using microperimetry. The cuticular drusen subtype was classified into 3 groups based on the SD-OCT findings. Age, BCVA, pattern standard deviation, area occupied by drusen, pupil size, and the false-positive rate were not significantly different (p > 0.05) according to the cuticular drusen type. The mean retinal sensitivity (MRS) (p = 0.063) and mean deviation (MD) (p = 0.098) showed marginally significant differences among the groups. In the subgroup analyses, type 1 and type 3 cuticular drusen showed significant differences in the MD (- 1.8 ± 2.1 vs - 5.1 ± 5.3; p = 0.011) and MRS (25.1 ± 2.2 vs 21.3 ± 5.7; p = 0.016) without differences in age, BCVA, or the area occupied by drusen (p > 0.05). The results indicate that depending on the subtypes of cuticular drusen type, the deterioration of retinal sensitivity is more likely to occur than decreased vision.

Neuroretinitis after the second injection of a SARS-CoV-2-vaccine: A case report.

Purpose: We report the first case of neuroretinitis after administration of a second dose of a messenger RNA vaccine for coronavirus disease-2019 (COVID-19). Observations: An 83-year-old healthy woman presented with subacute, painless, and progressive visual loss in the right eye that started 2 days after the second injection of the COVID-19 vaccine (Comirnaty®) from Pfizer (New York, NY, USA) and BioNTech (Mainz, Germany). Visual acuities were hand motion perception in the right eye and 20/30 in the left eye. There was optic nerve head swelling in the right eye and subretinal fluid and disruption of the photoreceptor layers in both eyes. Magnetic resonance imaging revealed an enhancement of the right optic nerve, consistent with optic neuritis. She was treated with intravenous corticosteroids, and the optic nerve swelling in the right eye resolved promptly. However, the amount of subretinal fluid worsened for 1 month and did not improve until 6 months from onset. Her visual acuity was slightly improved to finger count perception in the right eye and 20/20 in the left eye during an examination 6 months from onset. Conclusions and Importance: Considering the temporal relation between the second dose of vaccination and the symptom onset in our patient, the ophthalmic symptoms here reported might be considered a rare adverse effect of the Comirnaty® COVID-19 vaccine. Although a causal relationship is not established, to our knowledge, this is the first report of neuroretinitis after vaccination with Comirnaty®, and any further similar cases should be examined in detail.

Age-related macular degeneration eyes presenting with cuticular drusen and reticular pseudodrusen.

This study aimed to describe the clinical characteristics of age-related macular degeneration (AMD) eyes with both cuticular drusen (CD) and reticular pseudodrusen (RPD). Clinical records of patients diagnosed with CD or RPD with multimodal imaging was reviewed for patients diagnosed with both CD and RPD. The distribution patterns of CD (macular and diffuse type) and RPD (localized, intermediate, and diffuse type), presence of soft drusen, large drusen (> 200 µm), variant subretinal drusenoid deposits, and macular complications were investigated. Of the 220 eyes of 110 patients diagnosed with CD and 926 eyes of 463 patients diagnosed with RPD, 13 eyes of seven patients met the diagnostic criteria for both CD and RPD. The mean age at initial presentation was 71.4 ± 8.8 years and six patients were female. The mean subfoveal choroidal thickness was 143.8 ± 25.1 µm. The distribution of CD was of the macular type in all eyes. Distribution of RPD was localized in 11 eyes (84.6%) and intermediate in two eyes (15.4%). Soft drusen, large drusen, and variant subretinal drusenoid deposits were present in 13 (100%), 12 (92.3%) and, seven (53.8%) eyes, respectively. Macular neovascularization was observed in two eyes (15.4%). CD and RPD can coexist in eyes with AMD. Multimodal imaging should be used for AMD eyes with features suggestive of CD and RPD, considering the high likelihood of developing late AMD.

Genetic Influence on Choroidal Volume.

PURPOSE: To evaluate the degree of genetic influence on macular choroidal volume. DESIGN: A cross-sectional twin and family study. METHODS: In total, 353 Korean adults with healthy eyes from 78 households with 2 or more family members were included in the study. Macular choroidal volume was measured using spectral-domain optical coherence tomography with enhanced depth imaging at 9 macular subfields defined by the ETDRS. Demographics and clinical characteristics were investigated, including age, sex, axial length, hypertension, diabetes, drinking habits, and smoking status. The associations of these factors with macular choroidal volume were assessed using univariate and subsequent multivariate regression analyses while accounting for family structure. The heritability estimates of macular choroidal volume in total and at each of the 9 macular subfields were calculated after adjusting the covariates. RESULTS: Patients who were younger, male, and had a shorter axial length showed associations with greater choroidal volume (P < .001 for all 3 independent variables). The covariates-adjusted heritability (±standard error) of the total macular choroidal volume was 0.76 ± 0.06, and the heritabilities of choroidal volume at each subfield ranged from 0.55 ± 0.09 (inner temporal subfield) to 0.77 ± 0.08 (inner superior subfield). CONCLUSION: The macular choroidal volume is highly heritable.

Heritability of macular ganglion cell inner plexiform layer thickness as determined by optical coherence tomography: the Healthy Twin Study.

PURPOSE: To evaluate genetic influence on macular ganglion cell inner plexiform layer (GCIPL) thickness. METHODS: Macular GCIPL thickness was measured with optical coherence tomography in nine macular subfields defined by the E TDRS. Intraclass correlation coefficients (ICC) of GCIPL thickness by different types of family relationships were estimated to assess intrafamilial resemblance. Then, heritability of GCIPL thickness was estimated. RESULTS: Three hundred and sixty-one Korean adults from 89 families with normal healthy eyes were included. GCIPL thickness was highest in inner subfields and lowest in fovea. Monozygotic twin pairs showed significantly higher ICCs of GCIPL thickness in all subfields compared to those in parent-offspring pairs and sibling pairs. GCIPL thickness was highly heritable in the centre (0.71) and outer subfields but moderate to highly heritable in inner subfields. Heritability of GCIPL thickness in outer subfields was 0.69, 0.67, 0.72 and 0.68 for superior, inferior, temporal and nasal fields, respectively. Heritability of GCIPL thickness in inner subfields was 0.55, 0.56, 0.75 and 050 for superior, inferior, temporal and nasal subfields, respectively. CONCLUSION: Macular GCIPL thickness is significantly influenced by genetic factors. It varies according to subfields with moderate to high heritability in all subfields.

Differential Effect of the Metabolic Syndrome on the Incidence of Retinal Vein Occlusion in the Korean Population: A Nationwide Cohort Study.

Purpose: To investigate the impact of the metabolic syndrome (METS) on the incidence of retinal vein occlusion (RVO). Methods: This is a retrospective cohort study using Korean National Health Insurance System data. 23,153,600 subjects without previous history of RVO underwent a National Health Screening Program examination between 2009 and 2012. They were monitored for RVO development (registration of diagnostic code for RVO) until 2015. Presence of METS was defined using the data from the National Health Screening Program examination according to the revised criteria of the National Cholesterol Education Program Adult Treatment Panel III. A multivariate adjusted Cox regression analysis was used to reveal hazard ratios and 95% confidence interval for RVO development in the presence of METS. Results: The age of the subjects was 47.64 ± 13.51 years. In this cohort, 11,747,439 (50.7%) were male, 11,406,161 (49.3%) were female, and 6,398,071 subjects (27.6%) were diagnosed with METS. The overall incidence of RVO was 0.947 per 1000 person-years. The adjusted hazard ratio of RVO in the presence of METS was 1.458 (95% confidence interval, 1.440-1.475; P < 0.001) after adjusting for age, sex, smoking status, alcohol consumption, physical activity, and income. Among all of the criteria for METS diagnosis, elevated blood pressure was the greatest risk for RVO development (adjusted hazard ratio, 1.610; 95% confidence interval, 1.589-1.631; P < 0.001). Conclusions: METS and each of diagnostic criteria was associated with an increased risk of RVO development. Elevated blood pressure seems to be especially important factors for RVO development. Translational Relevance: Our results provide information about the link between METS and RVO.

Clinical manifestations of cuticular drusen in Korean patients.

Cuticular drusen show some similarities to and differences from soft drusen in age-related macular degeneration (AMD) and might thus be a unique AMD subtype. Previous studies on cuticular drusen were performed mainly in white ethnic groups, but AMD shows ethnic differences. We investigated clinical manifestations of cuticular drusen in Korean patients to evaluate possible ethnic differences. Clinical records of Korean patients with cuticular drusen were retrospectively reviewed. Fundus distribution pattern, imaging features, and presence of large drusen, drusenoid pigment epithelial detachment (PED), and macular complications, including geographic atrophy (GA), choroidal neovascularization (CNV), and acquired vitelliform lesion (AVL), were assessed via multimodal imaging in 162 eyes with cuticular drusen (n = 81 patients; 67 females; mean age: 66.6 ± 9.1 years). Diffuse distribution was found in 61.7% and peripapillary involvement in 75.3% of eyes. Large drusen, drusenoid PED, GA, CNV, and AVL were observed in 59.3%, 26.5%, 18.5%, 3.7%, and 1.2% of eyes, respectively. The macular complication prevalence was similar between patients ≤ 60 and those > 60 years old. In Korean patients, cuticular drusen were less frequently associated with macular complications than in white patients, and the proportion of macular complications differed significantly, with AVL representing an uncommon complication.

Differential effect of obesity on the incidence of retinal vein occlusion with and without diabetes: a Korean nationwide cohort study.

We aimed to evaluate the association between obesity and the incidence of retinal vein occlusion (RVO) with and without diabetes mellitus (DM).This is a retrospective cohort study using Korean National Health Insurance System data. The participants were 23,061,531 adults older than 20 years who received a health examination at least once between 2009 and 2012, and all patients were observed for RVO development until 2015. We used a multivariate adjusted Cox regression analysis to evaluate the association between RVO and body mass index (BMI) with and without DM. The analysis were evaluated via a hazard ratio (HR) and 95% confidence interval (CI). The age-, sex-, and multivariable-adjusted HRs for RVO were stratified by BMI. This population-based study revealed evidence that obesity has a different effect on the incidence of RVO in the presence and absence of DM.In people with DM, a lower BMI was associated with an increased risk of RVO, and a higher BMI was associated with a lower risk for RVO. In people without DM, the correlation was reversed: a lower BMI was associated with a lower risk for RVO and vice versa.

Heritability of Inner Retinal Layer and Outer Retinal Layer Thickness: The Healthy Twin Study.

The purpose of the study is to evaluate the heritability of inner retinal layer (IRL) and outer retinal layer (ORL) thicknesses in the healthy Korean population. This was a cross-sectional, twin and family study. We included 374 Korean adults with healthy eyes from 89 families. IRL thickness (from the internal limiting membrane to the external limiting membrane) and ORL thickness (from the external limiting membrane to the outer border of the retinal pigment epithelium layer) were measured in the nine macular subfields as defined by the Early Treatment of Diabetic Retinopathy Study using optical coherence tomography. The heritability on IRL and ORL thicknesses were investigated using a variance decomposition model. The heritability of IRL thickness was 0.87, 0.58, 0.85, 0.89, and 0.74 for the central, inner superior, inner inferior, inner temporal, inner nasal subfields, respectively; and 0.62, 0.83, 0.62, and 0.60 for the outer superior, outer inferior, outer temporal, outer nasal subfields, respectively. The heritability of ORL thickness was 0.56, 0.75, 0.66, 0.72, and 0.56 for the central, inner superior, inner inferior, inner temporal, inner nasal subfields, respectively; and 0.64, 0.63, 0.73, 0.54 for the outer superior, outer inferior, outer temporal, and outer nasal subfields, respectively. The heritability estimates of IRL thickness and ORL thickness ranged from moderate to high. The IRL thickness at the central, inner temporal, and inner inferior subfields had particularly high heritability.

Genetic influence on macular retinal nerve fibre layer thickness according to retinal subfield.

BACKGROUND/AIM: Characterising genetic effect on macular retinal nerve fibre layer (RNFL) is needed to obtain better understanding of various retinopathies and optic neuropathies. The purpose of this study was to evaluate genetic influence on macular RNFL thickness. METHODS: This is a cross-sectional, twin and family study. Three hundred and sixty-two Korean adults with healthy eyes were included in the study from 79 households with two or more family members. Macular RNFL thickness was measured with optical coherence tomography at nine macular subfields defined by the ETDRS. Intraclass correlation coefficients (ICCs) were estimated to assess intrafamilial resemblance of RNFL thickness by different types of family relationship. Heritability of RNFL thickness was evaluated using variance decomposition model. RESULTS: RNFL thickness increased from central subfield to outer subfields. Temporal quadrant RNFL was thinner compared with other quadrants. Monozygotic twin pairs showed the highest ICCs of RNFL thickness, although the ICC level varied across different subfields. Heritability of RNFL thickness was the highest at central subfield (0.81). RNFL thicknesses of outer subfields were moderately to highly heritable: 0.53, 0.71, 0.47 and 0.66 for superior, inferior, temporal and nasal fields, respectively. RNFL thicknesses at inner subfields showed the lowest heritability: 0.21, 0.24, 0.27 and 0.27 for superior, inferior, temporal and nasal subfields, respectively. CONCLUSION: Macular RNFL thickness is significantly influenced by genetic factors. It varies largely by subfields with the highest heritability at the central subfield and a relatively lower heritability at inner subfields.