Genetic associations of central serous chorioretinopathy subtypes, neovascular age-related macular degeneration, and polypoidal choroidal vasculopathy.

PURPOSE: To evaluate the genetic associations of different subtypes of central serous chorioretinopathy (CSCR), neovascular age-related macular degeneration (nAMD), and polypoidal choroidal vasculopathy (PCV). DESIGN: A case-control genetic association study. METHODS: This study enrolled 217 CSCR, 341 nAMD, 288 PCV patients, and 1380 controls. The CSCR patients were classified into those with focal or diffuse leakage, with or without pigment epithelial detachment (PED), and with or without macular neovascularization (MNV). Associations between 11 variants from 8 genes, ADAMTS9, ANGPT2, ARMS2, CFH, NR3C2, PGF, TNFRSF10A and VIPR2, and diseases/subtypes were analyzed by logistic regression analysis adjusted for age and sex, and inter-phenotype comparison by heterogeneity test. RESULTS: The CFH rs800292-A conferred a protective effect for CSCR with MNV (OR=0.44, P = 0.002) and a risk effect for CSCR without MNV (OR=1.31, P = 0.023). CSCR patients carrying rs800292-G had a 3.23-fold of increased risk towards developing secondary MNV (P = 1.45 ×10-4). CFH rs3753394, rs800292 and rs1329428 showed similar effects among CSCR with MNV, nAMD and PCV, but opposite effects on CSCR without MNV. TNFRSF10A rs13278062-T was associated with overall CSCR but not with CSCR subtypes, nAMD or PCV. Moreover, CFH and ARMS2 SNPs showed heterogeneous effects in CSCR without MNV against CSCR with MNV, nAMD and PCV. CONCLUSIONS: Genetic associations of CSCR with MNV resembled nAMD and PCV compared to CSCR without MNV, indicating differential genetic effects on neovascularization and choroidopathy. Further investigation of the functional roles of CFH, ARMS2, and TNFRSF10A in CSCR, nAMD and PCV should help elucidate the mechanisms of these maculopathies.

Comparing Half-Dose Photodynamic Therapy with Subthreshold Micropulse Laser for the Treatment of Central Serous Chorioretinopathy.

PURPOSE: To compare the anatomic and functional outcomes of half-dose photodynamic therapy (PDT) and yellow 577-nm subthreshold micropulse laser (SMLT) in treating patients with chronic central serous chorioretinopathy (CSCR). DESIGN: Prospective, double-masked, randomized, controlled clinical trial. PARTICIPANTS: Patients with chronic CSCR confirmed by clinical features and multimodal imaging. METHODS: Eligible patients were randomized (1:1) to receive half-dose PDT or SMLT. The same treatment was repeated if persistent subretinal fluid (SRF) was observed. Treatment responses were evaluated 1 month after treatment and every 3 months until the end point at 12 months. MAIN OUTCOME MEASURES: The primary outcome measure was the complete resolution of SRF on OCT scan at month 12. Secondary outcomes included the changes in best-corrected visual acuity (BCVA), central macular thickness (CMT) as measured by OCT, retinal sensitivity as measured by microperimetry, and vision-related quality of life using the National Eye Institute 25-Item Visual Function Questionnaire. RESULTS: Between April 2017 and October 2020, 68 patients were recruited. At 1 month after treatment, SRF resolved in 8 (24.2%) of 33 patients receiving SMLT and in 20 (58.8%) of 34 patients receiving half-dose PDT. This increased to 23 (82.1%) of 28 patients in the SMLT group and 30 (90.9%) of 33 patients in the half-dose PDT group at 12 months of follow-up. Kaplan-Meier survival curves showed significantly faster resolution of SRF in the half-dose PDT group than the SMLT group (P = 0.016). Both groups showed significant improvement in BCVA (-0.12 ± 0.21, P = 0.005 for SMLT; -0.13 ± 0.12, P < 0.001 for half-dose PDT), CMT (-154.2 ± 105.6, P < 0.001 for SMLT; -140.8 ± 94.0, P < 0.001 for half-dose PDT), and retinal sensitivity (5.70 ± 5.02, P < 0.001 for SMLT; 6.05 ± 3.83, P < 0.001 for half-dose PDT) at 12 months compared with baseline. There was no significant difference between the 2 treatment groups at each time point in all investigations except BCVA at 3 months (P = 0.03). CONCLUSIONS: When comparing half-dose PDT to subthreshold SMLT, this study has shown both treatments to be viable options, with half-dose PDT achieving faster anatomic success and functional improvement. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Cost-effectiveness of virtual reality and wet laboratory cataract surgery simulation.

PURPOSE: To evaluate the cost-effectiveness of phacoemulsification simulation training in virtual reality simulator and wet laboratory on operating theater performance. METHODS: Residents were randomized to a combination of virtual reality and wet laboratory phacoemulsification or wet laboratory phacoemulsification. A reference control group consisted of trainees who had wet laboratory training without phacoemulsification. All trainees were assessed on operating theater performance in 3 sequential cataract patients. International Council of Ophthalmology Surgical Competency Assessment Rubric-phacoemulsification (ICO OSCAR phaco) scores by 2 masked independent graders and cost data were used to determine the incremental cost-effectiveness ratio (ICER). A decision model was constructed to indicate the most cost-effective simulation training strategy based on the willingness to pay (WTP) per ICO OSCAR phaco score gained. RESULTS: Twenty-two trainees who performed phacoemulsification in 66 patients were analyzed. Trainees who had additional virtual reality simulation achieved higher mean ICO OSCAR phaco scores compared with trainees who had wet laboratory phacoemulsification and control (49.5 ± standard deviation [SD] 9.8 vs 39.0 ± 15.8 vs 32.5 ± 12.1, P < .001). Compared with the control group, ICER per ICO OSCAR phaco of wet laboratory phacoemulsification was $13,473 for capital cost and $2209 for recurring cost. Compared with wet laboratory phacoemulsification, ICER per ICO OSCAR phaco of additional virtual reality simulator training was US $23,778 for capital cost and $1879 for recurring cost. The threshold WTP values per ICO OSCAR phaco score for combined virtual reality simulator and wet laboratory phacoemulsification to be most cost-effective was $22,500 for capital cost and $1850 for recurring cost. CONCLUSIONS: Combining virtual reality simulator with wet laboratory phacoemulsification training is effective for skills transfer in the operating theater. Despite of the high capital cost of virtual reality simulator, its relatively low recurring cost is more favorable toward cost-effectiveness.

Multi-Polymorphism Analysis Reveals Joint Effects in Males With Chronic Central Serous Chorioretinopathy.

Purpose: Central serous chorioretinopathy (CSCR) is a leading cause of central vision impairment in the working-age population with male predilection. Knowledge about the genetic basis of CSCR and its male predilection remained limited. This study aimed to evaluate the association patterns of multiple gene variants in chronic CSCR (cCSCR) in Chinese patients. Methods: This case-control genetic association study included 531 patients with cCSCR and 2383 controls from two independent Chinese cohorts. Nine single-nucleotide polymorphisms (SNPs) of six genes, namely CFH, NR3C2, GATA5, VIPR2, TNFRSF10A, and ARMS2, were genotyped in all subjects. The main outcome measures were the association of individual single-nucleotide polymorphism (SNP) with cCSCR, the sex-stratification effects of individual SNP, and joint effects of different SNPs on cCSCR. Results: Association results in the two cohorts were consistent with low heterogeneities. In the combined analysis, SNPs CFH rs800292 (odds ratio [OR] = 1.25, P = 0.0020), CFH rs1329428 (OR = 1.23, P = 0.0037), and TNFRSF10A rs13278062 (OR = 1.43, P = 0.0014) were significantly associated with cCSCR. In stratification analysis by sex, 3 SNPs in CFH, rs3753394, rs800292, and rs1329428, were associated with cCSCR in male patients, but not in female patients. Joint analysis revealed that subjects homozygous for the risk alleles of CFH rs800292 and TNFRSF10A rs13278062 had over 4-fold of increased risk of cCSCR when compared with subjects homozygous for the non-risk alleles (OR = 4.06, P = 2.30 × 10-5). Conclusions: This study revealed main and joint effects of SNPs in CFH and TNFRSF10A on cCSCR, and suggested CFH as a potential genetic factor underlying the male predilection of cCSCR. Further replication in other study populations is needed.

Myopic macular diseases: A review.

Recent evidence has demonstrated that the global public health burden of myopia is rising rapidly. Highly myopic eyes are associated with increased frequency of eye disorders that can lead to irreversible visual impairment. With recent technological advancement in ophthalmic imaging modalities, various macular complications associated with pathologic myopia are being elucidated. The development and progression of myopic chorioretinal atrophy, myopic macular neovascularization, myopic traction maculopathy and dome-shaped macula are vision-threatening myopic macular diseases. In order to overcome the challenges in managing patients with pathologic myopia, it is important to have a complete understanding in the natural course of these myopic macular diseases. Standardising the classification criteria of pathologic myopia is essential for enhancing clinical surveillance. Personalised pharmaceutical therapy and surgical interventions will help to optimise the treatment outcomes in patients suffering from these myopic macular diseases.

Oculoplastic surgical simulation using goat sockets.

PURPOSE: To describe a reproducible and easily available goat socket model for training of various oculoplastic operations, and to evaluate trainees' perception of this training model in terms of their learning progress and satisfaction. METHODS: Goat sockets including orbital rim and eye with eyelids were harvested in form of a split-head model. Ophthalmology residents underwent individual surgical training using the goat socket model, supervised by an oculoplastic attending. Participants completed a questionnaire in form of a 5-point Likert Scale to evaluate their learning progress and satisfaction. OUTCOME MEASURES: Types of oculoplastic operations performed using the goat socket models, and participants' rating of their learning progress and satisfaction were reported. RESULTS: A wide range of oculoplastic operations including both eyelid and orbital operations could be simulated because of similarities of the goat eye model to the human eye anatomy. Fifteen ophthalmic trainees participated in surgical training using the goat eye model. All (100%) participants agreed that surgical simulation using the goat socket model increased their skills in surgical instrumentation and carrying out surgical steps, and their confidence in operating on patients. Most (87%) agreed the model resembled reasonably well compared to surgeries in human, and 93% would recommend training with the model to fellow resident ophthalmologists before operating on human patients. CONCLUSIONS: Oculoplastic surgical training using goat sockets is simple, readily available, and inexpensive. Trainee users showed promising feedback and positive learning progress using the goat socket model.

Safety review of anti-VEGF therapy in patients with myopic choroidal neovascularization.

INTRODUCTION: Anti-angiogenesis therapy with intravitreal anti-VEGF agents is now the standard-of-care treatment for myopic choroidal neovascularization (CNV). AREAS COVERED: We provide a critical review of the safety of all the anti-VEGF agents currently used for treating myopic CNV including ranibizumab, aflibercept, conbercept, bevacizumab, and ziv-aflibercept. EXPERT OPINION: Anti-VEGF therapy for myopic CNV with the currently available anti-VEGF drugs generally have favorable safety outcomes in the short-term. Nonetheless, ocular adverse events following anti-VEGF therapy for myopic CNV may develop and these include worsening or new development of myopic traction maculopathy, increased risk of retinal detachment, and progression of chorioretinal atrophy. Clinicians should be aware of these potential complications and evaluate them before and after anti-VEGF therapy.

A Multitask Deep-Learning System to Classify Diabetic Macular Edema for Different Optical Coherence Tomography Devices: A Multicenter Analysis.

OBJECTIVE: Diabetic macular edema (DME) is the primary cause of vision loss among individuals with diabetes mellitus (DM). We developed, validated, and tested a deep learning (DL) system for classifying DME using images from three common commercially available optical coherence tomography (OCT) devices. RESEARCH DESIGN AND METHODS: We trained and validated two versions of a multitask convolution neural network (CNN) to classify DME (center-involved DME [CI-DME], non-CI-DME, or absence of DME) using three-dimensional (3D) volume scans and 2D B-scans, respectively. For both 3D and 2D CNNs, we used the residual network (ResNet) as the backbone. For the 3D CNN, we used a 3D version of ResNet-34 with the last fully connected layer removed as the feature extraction module. A total of 73,746 OCT images were used for training and primary validation. External testing was performed using 26,981 images across seven independent data sets from Singapore, Hong Kong, the U.S., China, and Australia. RESULTS: In classifying the presence or absence of DME, the DL system achieved area under the receiver operating characteristic curves (AUROCs) of 0.937 (95% CI 0.920-0.954), 0.958 (0.930-0.977), and 0.965 (0.948-0.977) for the primary data set obtained from CIRRUS, SPECTRALIS, and Triton OCTs, respectively, in addition to AUROCs >0.906 for the external data sets. For further classification of the CI-DME and non-CI-DME subgroups, the AUROCs were 0.968 (0.940-0.995), 0.951 (0.898-0.982), and 0.975 (0.947-0.991) for the primary data set and >0.894 for the external data sets. CONCLUSIONS: We demonstrated excellent performance with a DL system for the automated classification of DME, highlighting its potential as a promising second-line screening tool for patients with DM, which may potentially create a more effective triaging mechanism to eye clinics.

Fundus Autofluorescence and Optical Coherence Tomography Characteristics in Different Stages of Central Serous Chorioretinopathy.

OBJECTIVE: To describe the morphological changes on fundus autofluorescence (FAF) and spectral-domain optical coherence tomography (SD-OCT) imaging at different chronicity of central serous chorioretinopathy (CSC). METHODS: This cross-sectional study included patients with CSC of different chronicity. Changes in FAF scans and morphological changes on SD-OCT were evaluated and compared at different stages of CSC. RESULTS: Sixty-nine patients were enrolled in the study, with a mean age of 52.1 ± 11.8 years. A distinct hypoautofluorescence (AF) pattern was observed at the leakage point in acute CSC (100%). The leakage site was indistinguishable in 48% of the patients with late-chronic CSC. The majority of acute CSC patients showed hyper-AF in the area of serous retinal detachment (SRD), which persisted in the early-chronic stage of CSC. In late-chronic CSC, many cases of hypo-AF (22.2%) and mixed-pattern AF (14.8%) were observed. SD-OCT revealed evolving features of retinal pigment epithelium (RPE) abnormalities in a time-dependent manner: from peaked PEDs in acute CSC to low-lying PEDs in early-chronic CSC and, eventually, flat, irregular PEDs in late-chronic CSC. The average thickness of the photoreceptor layer (inner and outer segment; IS/OS) was 79 µm in the acute group and 55.2 µm in the chronic group. The photoreceptor layer (IS/OS) height was positively associated with visual acuity (p=0.002). CONCLUSION: Different stages of CSC present different patterns on FAF and SD-OCT imaging. Chronicity of CSC can be estimated using specific features in these images. Photoreceptor layer (IS/OS) height acts as a good and objective predictor of visual outcomes in CSC patients.

Optical coherence tomography angiography in diabetic retinopathy: an updated review.

Diabetic retinopathy (DR) is a common microvascular complication of diabetes mellitus. Optical coherence tomography angiography (OCTA) has been developed to visualize the retinal microvasculature and choriocapillaris based on the motion contrast of circulating blood cells. Depth-resolved ability and non-invasive nature of OCTA allow for repeated examinations and visualization of microvasculature at the retinal capillary plexuses and choriocapillaris. OCTA enables quantification of microvascular alterations in the retinal capillary network, in addition to the detection of classical features associated with DR, including microaneurysms, intraretinal microvascular abnormalities, and neovascularization. OCTA has a promising role as an objective tool for quantifying extent of microvascular damage and identify eyes with diabetic macular ischaemia contributed to visual loss. Furthermore, OCTA can identify preclinical microvascular abnormalities preceding the onset of clinically detectable DR. In this review, we focused on the applications of OCTA derived quantitative metrics that are relevant to early detection, staging and progression of DR. Advancement of OCTA technology in clinical research will ultimately lead to enhancement of individualised management of DR and prevention of visual impairment in patients with diabetes.

Ranibizumab for myopic choroidal neovascularization.

INTRODUCTION: Myopic choroidal neovascularization (CNV) is one of the most vision-threatening complications in patients with pathologic myopia. Over the last decade, anti-angiogenesis therapy with anti-vascular endothelial growth factor (anti-VEGF) agents has become the standard-of-care treatment for myopic CNV and ranibizumab has been approved for treating myopic CNV. AREAS COVERED: Review of preclinical studies and clinical trials data supporting the use of ranibizumab for myopic CNV. Discussion on the mechanisms, efficacy, safety, regulatory affairs, and future directions of ranibizumab for myopic CNV are highlighted. EXPERT OPINION: Ranibizumab has demonstrated good efficacy and safety profile in multiple clinical trials and long-term studies for treating myopic CNV. Cost-effective analysis has shown that ranibizumab therapy is a cost-effective treatment for myopic CNV. Among the currently available anti-VEGF agents, ranibizumab is the only drug that is approved for the treatment of myopic CNV by the US Food and Drug Administration. In the coming few years, biosimilars of ranibizumab may become available and will have the potential to lower the cost of ranibizumab. Long-term visual gain after ranibizumab treatment for myopic CNV is limited by chorioretinal atrophy associated with pathologic myopia and further research is required to tackle the development of chorioretinal atrophy.

Clinically relevant factors associated with quantitative optical coherence tomography angiography metrics in deep capillary plexus in patients with diabetes.

BACKGROUND: To test clinically relevant factors associated with quantitative artifact-free deep capillary plexus (DCP) metrics in patients with diabetes mellitus (DM). METHODS: 563 eligible eyes (221 with no diabetic retinopathy [DR], 135 with mild DR, 130 with moderate DR, and 77 with severe DR) from 334 subjects underwent optical coherence tomography-angiography (OCT-A) with a swept-source OCT (Triton DRI-OCT, Topcon, Inc., Tokyo, Japan). Strict criteria were applied to exclude from analysis those DCP images with artifacts and of poor quality, including projection artifacts, motion artifacts, blurriness, signal loss, B-scan segmentation error, or low-quality score. A customized MATLAB program was then used to quantify DCP morphology from the artifact-free DCP images by calculating three metrics: foveal avascular zone (FAZ), vessel density (VD), and fractal dimension (FD). RESULTS: 166 (29.5%) eyes were excluded after quality control, leaving in the analysis 397 eyes (170 with no DR, 101 with mild DR, 90 with moderate DR, 36 with severe DR) from 250 subjects. In the multiple regression models, larger FAZ area was associated with more severe DR (ß = 0.687; p = 0.037), shorter axial length (AL) (ß = - 0.171; p = 0.003), thinner subfoveal choroid thickness (ß = - 0.122; p = 0.031), and lower body mass index (BMI) (ß = - 0.090; p = 0.047). Lower VD was associated with more severe DR (ß = - 0.842; p = 0.001), shorter AL (ß = 0.107; p = 0.039), and poorer visual acuity (VA) (ß = - 0.133; p = 0.021). Lower FD was associated with more severe DR (ß = - 0.891; p < 0.001) and with older age (ß = - 0.142; p = 0.004). CONCLUSIONS: Quantitative artifact-free DCP metrics are associated with VA, DR severity, AL, subfoveal choroidal thickness, age, and BMI in diabetic patients. The effects of ocular and systemic factors should be considered for meaningful interpretations of DCP changes in DM patients.

High prevalence of myopia in children and their parents in Hong Kong Chinese Population: the Hong Kong Children Eye Study.

PURPOSE: To determine the myopia prevalence in Hong Kong Chinese children and their parents. METHODS: It was a population-based cross-sectional study. A total of 4257 children aged 6-8 years, and 5880 parents were recruited in the Hong Kong Children Eye Study. Cycloplegic autorefraction was measured for children; and non-cycloplegic autorefraction for parents. Parental educational level, children's outdoor time, and near work were collected by validated questionnaires. RESULTS: In children aged 6-8 years, 25.0% were myopic, and among them, 12.7% for the 6-year-olds, 24.4% for the 7-year-olds and 36.1% for the 8-year-old. About 0.7% of children aged 8 years were high myopia. In all age groups, boys (their myopia rate: 13.9% at 6 years, 26.7% at 7 years, and 38.3% at 8 years) were more myopic than girls (11.3% at 6 years, 22.0% at 7 years, 33.4% at 8 years). Among parents, 72.2% were myopic (mother, 73.2%; father, 70.7%) and 13.5% high myopia (mother, 12.8%; father, 14.5%). It was observed that prevalence decreased with ages and increased with education level. CONCLUSION: There is a strikingly high prevalence of myopia in Hong Kong children aged 6-8, much higher than that of other regions of China. Of note, the prevalence of children was similar to that in 15 years ago. Furthermore, the myopia prevalence of parents is high, and it had already increased in this cohort. Prevention of childhood myopia is important, likewise for visual complications from high myopia in adults.

OCT Angiography Metrics Predict Progression of Diabetic Retinopathy and Development of Diabetic Macular Edema: A Prospective Study.

PURPOSE: To prospectively determine the relationship of OCT angiography (OCTA) metrics to diabetic retinopathy (DR) progression and development of diabetic macular edema (DME). DESIGN: Prospective, observational study. PARTICIPANTS: A total of 205 eyes from 129 patients with diabetes mellitus followed up for at least 2 years. METHODS: All participants underwent OCTA with a swept-source OCT device (DRI-OCT Triton, Topcon, Inc, Tokyo, Japan). Individual OCTA images of superficial capillary plexus (SCP) and deep capillary plexus (DCP) were generated by IMAGEnet6 (Basic License 10). After a quality check, automated measurements of foveal avascular zone (FAZ) area, FAZ circularity, vessel density (VD), and fractal dimension (FD) of both SCP and DCP were then obtained. MAIN OUTCOME MEASURES: Progression of DR and development of DME. RESULTS: Over a median follow-up of 27.14 months (interquartile range, 24.16-30.41 months), 28 of the 205 eyes (13.66%) developed DR progression. Of the 194 eyes without DME at baseline, 17 (8.76%) developed DME. Larger FAZ area (hazard ratio [HR], 1.829 per SD increase; 95% confidence interval [CI], 1.332-2.512), lower VD (HR, 1.908 per SD decrease; 95% CI, 1.303-2.793), and lower FD (HR, 4.464 per SD decrease; 95% CI, 1.337-14.903) of DCP were significantly associated with DR progression after adjusting for established risk factors (DR severity, glycated hemoglobin, duration of diabetes, age, and mean arterial blood pressure at baseline). Lower VD of SCP (HR, 1.789 per SD decrease; 95% CI, 1.027-4.512) was associated with DME development. Compared with the model with established risk factors alone, the addition of OCTA metrics improved the predictive discrimination of DR progression (FAZ area of DCP, C-statistics 0.723 vs. 0.677, P < 0.001; VD of DCP, C-statistics 0.727 vs. 0.677, P = 0.001; FD of DCP, C-statistics 0.738 vs. 0.677, P < 0.001) and DME development (VD of SCP, C-statistics 0.904 vs. 0.875, P = 0.036). CONCLUSIONS: The FAZ area, VD, and FD of DCP predict DR progression, whereas VD of SCP predicts DME development. Our findings provide evidence to support that OCTA metrics improve the evaluation of risk of DR progression and DME development beyond traditional risk factors.

Choroidal thickness in thyroid-associated orbitopathy.

IMPORTANCE: To investigate the choroidal thickness (CT) in patients with thyroid-associated orbitopathy (TAO). BACKGROUND: To compare CT of TAO patients and healthy subjects. DESIGN: Prospective cross-sectional study in a public hospital. PARTICIPANTS: One hundred and four eyes of 52 TAO patients and 52 eyes of 26 healthy subjects. METHODS: CT was measured with enhanced-depth imaging optical coherence tomography (EDI-OCT) at the subfoveal, macular and peripapillary regions. Multivariate linear regression was used to evaluate the associations of subfoveal CT with systemic and ocular variables among TAO eyes. MAIN OUTCOME MEASURES: CT of both groups. RESULTS: CT of eyes with TAO was significantly increased at the subfoveal region, 1 and 2 mm from the fovea nasally, temporally and superiorly, and 1 mm inferior to the fovea (all P < .05). No significant difference was found in CT at 2 mm inferior to the fovea (P = .094) and all four quadrants of the peripapillary region (superior, P = .096; nasal, P = .732; inferior, P = .179; temporal, P = .052). Among TAO eyes, thinner subfoveal choroid was associated with worsening exophthalmos (P = .043), poorer visual acuity (P = .017), increasing age (P = .040) and axial length (P < .001). There was no association between CT and clinical activity score (P = .239). CONCLUSIONS AND RELEVANCE: TAO patients showed thicker choroid than controls over the macula, but not the peripapillary regions. Thinner subfoveal choroid was associated with worsening exophthalmos and poorer vision. EDI-OCT can monitor choroidal vascular changes associated with TAO and its complications.

Non-mydriatic ultrawide field scanning laser ophthalmoscopy compared with dilated fundal examination for assessment of diabetic retinopathy and diabetic macular oedema in Chinese individuals with diabetes mellitus.

AIMS: To evaluate the performance of ultrawide field scanning laser ophthalmoscopy (UWF-SLO) for assessing diabetic retinopathy (DR) and diabetic macular oedema (DME) in a Chinese population, compared with clinical examination. METHODS: This is a retrospective cohort study. A series of 322 eyes from 164 patients with DM were included. Each patient underwent both dilated fundal examination with DR and DME grading by retina specialist and non-mydriatic 200° UWF-SLO (Daytona, Optos, Dunfermline, UK). The severity of DR and DME from UWF-SLO images was further graded by ophthalmologists, according to both international clinical DR and DME disease severity scales and the standard 7-field Early Treatment Diabetic Retinopathy Study (ETDRS) scale. Any DR, DME and vision-threatening DR (VTDR) were treated as endpoints for this study. RESULTS: 23 out of 322 images (7.14%), including all four cases with proliferative DR on clinical examinations, were determined as ungradable. When the international scale was used for grading UWF-SLO images, the sensitivity of any DR, DME and VTDR was 67.7%, 67.4% and 72.6%, respectively; the specificity of any DR, DME and VTDR was 97.8%, 97.3% and 97.8%, respectively. The agreement with clinical grading in picking up any DR, DME and VTDR was substantial, with κ-values of 0.634, 0.694 and 0.707, respectively. The performance of UWF-SLO was shown to be lower when ETDRS scale was used for grading the images. CONCLUSION: The performance of non-mydriatic UWF-SLO is comparable in identifying DR with that of clinical examination in a Chinese cohort. However, whether UWF-SLO can be considered as tool for screening DR is still undetermined.

Relationship of intercapillary area with visual acuity in diabetes mellitus: an optical coherence tomography angiography study.

AIM: To examine the correlation of best-corrected visual acuity (BCVA) with intercapillary area (ICA) measured from optical coherence tomography angiography (OCT-A) in patients with diabetes, and to compare the strength of associations between BCVA with ICA and other OCT-A metrics. METHODS: A cross-sectional study involved 447 eyes from 299 patients with diabetes. All participants underwent OCT-A with a swept-source OCT (Triton DRI-OCT, Topcon, Tokyo, Japan). An automated customised MATLAB programme was used to quantify ICA (the mean of the 10 largest areas including foveal avascular zone (FAZ) area (ICA10_FAZ) and excluding FAZ area (ICA10_excFAZ)) and other OCT-A metrics (FAZ area, FAZ circularity and vessel density) from the macular OCT-A images. BCVA was measured using Snellen chart for the patients and then converted to logarithm of the minimum angle of resolution (logMAR) VA. We further defined 'good VA' as Snellen >0.7 and 'poor VA' as Snellen ≤0.7 as a binary VA outcome for logistic regression analysis. RESULTS: In univariate regression analysis, increased ICA10_FAZ and ICA10_excFAZ were significantly correlated with logMAR (p values <0.05). In multivariate regression analysis, only the association between ICA10_FAZ and logMAR persisted (ß=0.103, p=0.024). In multivariable logistic regression analysis, increased ICA10_FAZ (OR=1.300, 95% CI 1.076 to 1.679, p=0.044) and FAZ circularity (OR=1.285, 95% CI 1.031 to 1.603, p=0.026) showed significant associations with poor VA. CONCLUSIONS: Increased ICA measured from OCT-A, describing enlargement of capillary rarefaction or closure at macular area, is independently associated with BCVA, suggesting that ICA is a potential marker to quantify retinal microvascular abnormalities relating to vision among individuals with diabetes.

Author Correction: Determinants of Quantitative Optical Coherence Tomography Angiography Metrics in Patients with Diabetes.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.