Diagnostic Challenges in ABCA4-Associated Retinal Degeneration: One Gene, Many Phenotypes.

(1) Purpose: ABCA4-associated retinal degeneration (ABCA4-RD) is a phenotypically diverse disease that often evades diagnosis, even by experienced retinal specialists. This may lead to inappropriate management, delayed genetic testing, or inaccurate interpretation of genetic testing results. Here, we illustrate the phenotypic diversity of ABCA4-RD using a series of representative cases and compare these to other conditions that closely mimic ABCA4-RD. (2) Methods: Genetically confirmed ABCA4-RD cases with representative phenotypes were selected from an inherited retinal disease cohort in Singapore and compared to phenocopies involving other retinal diseases. (3) Results: ABCA4-RD phenotypes in this series included typical adolescent-onset Stargardt disease with flecks, bull's eye maculopathy without flecks, fundus flavimaculatus, late-onset Stargardt disease, and severe early-onset Stargardt disease. Phenocopies of ABCA4-RD in this series included macular dystrophy, pattern dystrophy, cone dystrophy, advanced retinitis pigmentosa, Leber congenital amaurosis, drug toxicity, and age-related macular degeneration. Key distinguishing features that often suggested a diagnosis of ABCA4-RD were the presence of peripapillary sparing, macular involvement and centrifugal distribution, and a recessive pedigree. (4) Conclusions: ABCA4-RD demonstrates a remarkable phenotypic spectrum that makes diagnosis challenging. Awareness of the clinical spectrum of disease can facilitate prompt recognition and accurate diagnostic testing.

RETINITIS PIGMENTOSA ASSOCIATED WITH THE EYS C2139Y VARIANT : An Important Cause of Blindness in East Asian Populations.

PURPOSE: The study aimed to describe the phenotypic features of retinitis pigmentosa (RP) associated with the previously described EYS C2139Y variant in Singaporeans and establish the importance of this variant as a prevalent cause of RP among East Asians. METHODS: A clinical phenotyping and exome-sequencing study was conducted on consecutive patients with nonsyndromic RP. Epidemiological analysis was performed using Singaporean and global population-based genetic data. RESULTS: A study of 150 consecutive unrelated individuals with nonsyndromic RP found that 87 (58%) of cases had plausible genotypes. A previously described missense variant in the EYS gene, 6416G>A (C2139Y), occurred heterozygously or homozygously in 17 of 150 families (11.3%), all with autosomal recessive RP. Symptom onset in EYS C2139Y-related RP ranged from 6 to 45 years, with visual acuity ranging from 20/20 at 21 years to no light perception by 48 years. C2139Y-related RP had typical findings, including sectoral RP in cases with EYS E2703X in trans . The median age at presentation was 45 years and visual fields declined to less than 20° (Goldmann V4e isopter) by age 65 years. Intereye correlation for visual acuity, fields, and ellipsoid band width was high (r 2 = 0.77-0.95). Carrier prevalence was 0.66% (allele frequency of 0.33%) in Singaporean Chinese and 0.34% in East Asians, suggesting a global disease burden exceeding 10,000 individuals. CONCLUSION: The EYS C2139Y variant is common in Singaporean RP patients and other ethnic Chinese populations. Targeted molecular therapy for this single variant could potentially treat a significant proportion of RP cases worldwide.

The economic burden of inherited retinal disease in Singapore: a prevalence-based cost-of-illness study.

OBJECTIVE: To assess the economic impact of inherited retinal disease (IRD) among Singaporeans. METHODS: IRD prevalence was calculated using population-based data. Focused surveys were conducted for sequentially enrolled IRD patients from a tertiary hospital. The IRD cohort was compared to the age- and gender-matched general population. Economic costs were expanded to the national IRD population to estimate productivity and healthcare costs. RESULTS: National IRD caseload was 5202 cases (95% CI, 1734-11273). IRD patients (n = 95) had similar employment rates to the general population (67.4% vs. 70.7%; p = 0.479). Annual income was lower among IRD patients than the general population (SGD 19,500 vs. 27,161; p < 0.0001). Employed IRD patients had lower median income than the general population (SGD 39,000 vs. 52,650; p < 0.0001). Per capita cost of IRD was SGD 9382, with a national burden of SGD 48.8 million per year. Male gender (beta of SGD 6543, p = 0.003) and earlier onset (beta of SGD 150/year, p = 0.009) predicted productivity loss. Treatment of the most economically impacted 10% of IRD patients with an effective IRD therapy required initial treatment cost of less than SGD 250,000 (USD 188,000) for cost savings to be achieved within 20 years. CONCLUSIONS: Employment rates among Singaporean IRD patients were the same as the general population, but patient income was significantly lower. Economic losses were driven in part by male patients with early age of onset. Direct healthcare costs contributed relatively little to the financial burden.

Review of Retinal Imaging Modalities for Hydroxychloroquine Retinopathy.

This review provides an overview of conventional and novel retinal imaging modalities for hydroxychloroquine (HCQ) retinopathy. HCQ retinopathy is a form of toxic retinopathy resulting from HCQ use for a variety of autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus. Each imaging modality detects a different aspect of HCQ retinopathy and shows a unique complement of structural changes. Conventionally, spectral-domain optical coherence tomography (SD-OCT), which shows loss or attenuation of the outer retina and/or retinal pigment epithelium-Bruch's membrane complex, and fundus autofluorescence (FAF), which shows parafoveal or pericentral abnormalities, are used to assess HCQ retinopathy. Additionally, several variations of OCT (retinal and choroidal thickness measurements, choroidal vascularity index, widefield OCT, en face imaging, minimum intensity analysis, and artificial intelligence techniques) and FAF techniques (quantitative FAF, near-infrared FAF, fluorescence lifetime imaging ophthalmoscopy, and widefield FAF) have been applied to assess HCQ retinopathy. Other novel retinal imaging techniques that are being studied for early detection of HCQ retinopathy include OCT angiography, multicolour imaging, adaptive optics, and retromode imaging, although further testing is required for validation.

Characterizing the genotypic spectrum of retinitis pigmentosa in East Asian populations: a systematic review.

BACKGROUND: Ongoing trials for retinitis pigmentosa (RP) are genotype-specific, with most trials conducted on European cohorts. Due to genetic differences across diverse ancestries and populations, these therapies may not be efficacious in East Asians. MATERIALS AND METHODS: A literature search was conducted from 1966 to September 2022 for cohort studies on East Asian populations reporting on non-syndromic RP genotypes and variants. Population-weighted prevalence was used to determine the genotypes and individual variants across the entire cohort. The carrier prevalence of common variants was compared against those in Europe. RESULTS: A total of 12 articles describing 2,932 clinically diagnosed East Asian RP probands were included. We identified 876 variants across 54 genes. The most common genotypes included USH2A, EYS, RPGR, ABCA4, PRPF31, RHO, RP1, RP2, PDE6B and SNRNP200, with USH2A as the most common (17.1%). Overall, 60.5% of probands with clinically relevant variants were found to have one of the genotypes above, with 543/876 (62.0%) of the variants occurring in these genes. The most frequently reported variant was USH2A missense variant c.2802T>G/p.C934W (4.9%). Carrier prevalence of these variants was significantly different (p < 0.0001) than in Europe. CONCLUSIONS: USH2A was the most commonly affected RP gene in this East Asian cohort, although sub-population analysis revealed distinct genotype prevalence patterns. While the genotypes are similar between East Asia and European cohorts, variants are specific to East Asia. The identification of several prevalent variants in USH2A and EYS provides an opportunity for the development of therapeutics that are relevant for East Asia patients.

Retinal neural dysfunction in diabetes revealed with handheld chromatic pupillometry.

BACKGROUND: To evaluate the ability of handheld chromatic pupillometry to reveal and localise retinal neural dysfunction in diabetic patients with and without diabetic retinopathy (DR). METHODS: This cross-sectional study included 82 diabetics (DM) and 93 controls (60.4 ± 8.4 years, 44.1% males). DM patients included those without (n = 25, 64.7 ± 6.3 years, 44.0% males) and with DR (n = 57, 60.3 ± 8.5 years, 64.9% males). Changes in horizontal pupil radius in response to blue (469 nm) and red (640 nm) light stimuli were assessed monocularly, in clinics, using a custom-built handheld pupillometer. Pupillometric parameters (phasic constriction amplitudes [predominantly from the outer retina], maximal constriction amplitudes [from the inner and outer retina] and post-illumination pupillary responses [PIPRs; predominantly from the inner retina]) were extracted from baseline-adjusted pupillary light response traces and compared between controls, DM without DR, and DR. Net PIPR was defined as the difference between blue and red PIPRs. RESULTS: Phasic constriction amplitudes to blue and red lights were decreased in DR compared to controls (p < 0.001; p < 0.001). Maximal constriction amplitudes to blue and red lights were decreased in DR compared to DM without DR (p < 0.001; p = 0.02), and in DM without DR compared to controls (p < 0.001; p = 0.005). Net PIPR was decreased in both DR and DM without DR compared to controls (p = 0.02; p = 0.03), suggesting a wavelength-dependent (and hence retinal) pupillometric dysfunction in diabetic patients with or without DR. CONCLUSIONS: Handheld chromatic pupillometry can reveal retinal neural dysfunction in diabetes, even without DR. Patients with DM but no DR displayed primarily inner retinal dysfunction, while patients with DR showed both inner and outer retinal dysfunction.

Efficacy of a novel personalised aflibercept monotherapy regimen based on polypoidal lesion closure in participants with polypoidal choroidal vasculopathy.

PURPOSE: To compare the efficacy of aflibercept using a personalised versus fixed regimen in treatment-naïve participants with polypoidal choroidal vasculopathy (PCV). DESIGN: A 52-week, randomised, open-label, non-inferiority, single-centre study that included participants with symptomatic PCV. Participants were randomised (3:1 ratio) to receive either personalised (n=40) or fixed 8-weekly treatment regimen (n=13). The personalised regimen allowed for either early treat and extend (T&E) after week 12 or late T&E with 3 additional 4-weekly aflibercept injections until week 24 in participants with residual polypoidal lesions (PL) on indocyanine green angiography (ICGA) at week 12. MAIN OUTCOMES AND MEASURES: Non-inferiority of personalised to fixed regimen for mean change in best-corrected visual acuity (BCVA) from baseline to week 52 (non-inferiority margin: -5 letters). The key secondary outcomes include reduction in central subfield thickness (CSFT) on optical coherence tomography and the anatomical closure of PL on ICGA. RESULTS: Of the 53 participants, the mean (SD) age was 69.2 (8.1) years, 19 (35.8 %) were male. Personalised group was non-inferior to fixed for the primary end point (+8.1 vs +7.9 letters at week 52, respectively; difference 0.16, 95% CI -2.8 to 2.4, p=0.79). There was greater reduction in mean CSFT (SD) in the personalised versus fixed group (-248.8 (169.9) vs -164.8 (148.9) µm, p=0.03). Closure of PL occurred in 21 (55.2%) and 5 (41.6%) of study eyes in personalised and fixed groups, respectively at week 52 (p=0.41). CONCLUSIONS: Personalised regimen achieved non-inferior BCVA gain and numerically higher PL closure compared with fixed regimen. TRIAL REGISTRATION NUMBER: NCT03117634.

Identifying the content for an item bank and computerized adaptive testing system to measure the impact of age-related macular degeneration on health-related quality of life.

PURPOSE: We are developing an age-related macular degeneration (AMD) health-related quality of life (HRQoL) item bank, applicable to Western and Asian populations. We report primarily on content generation and refinement, but also compare the HRQoL issues reported in our study with Western studies and current AMD-HRQoL questionnaires. METHODS: In this cross-sectional, qualitative study of AMD patients attending the Singapore National Eye Centre (May-December 2019), items/domains were generated from: (1) AMD-specific questionnaires; (2) published articles; (3) focus groups/semi-structured interviews with AMD patients (n = 27); and (4) written feedback from retinal experts. Following thematic analysis, items were systematically refined to a minimally representative set and pre-tested using cognitive interviews with 16 AMD patients. RESULTS: Of the 27 patients (mean ± standard deviation age 67.9 ± 7.0; 59.2% male), 18 (66.7%), two (7.4%), and seven (25.9%) had no, early-intermediate, and late/advanced AMD (better eye), respectively. Whilst some HRQoL issues, e.g. activity limitation, mobility, lighting, and concerns were similarly reported by Western patients and covered by other questionnaires, others like anxiety about intravitreal injections, work tasks, and financial dependency were novel. Overall, 462 items within seven independent HRQoL domains were identified: Activity limitation, Lighting, Mobility, Emotional, Concerns, AMD management, and Work. Following item refinement, items were reduced to 219, with 31 items undergoing amendment. CONCLUSION: Our 7-domain, 219-item AMD-specific HRQoL instrument will undergo psychometric testing and calibration for computerized adaptive testing. The future instrument will enable users to precisely, rapidly, and comprehensively quantify the HRQoL impact of AMD and associated treatments, with item coverage relevant across several populations.

OPTICAL COHERENCE TOMOGRAPHY FEATURES OF POLYPOIDAL LESION CLOSURE IN POLYPOIDAL CHOROIDAL VASCULOPATHY TREATED WITH AFLIBERCEPT.

PURPOSE: To evaluate whether optical coherence tomography (OCT) can determine polypoidal lesion (PL) perfusion in polypoidal choroidal vasculopathy eyes after 12 months of aflibercept monotherapy. Polypoidal lesion perfusion status, assessed by indocyanine green angiography, is an important anatomical outcome in polypoidal choroidal vasculopathy management. METHODS: Post hoc data from a prospective randomized, open-label, study in eyes with polypoidal choroidal vasculopathy undergoing monotherapy with aflibercept evaluated PL perfusion status based on indocyanine green angiography (gold standard) and OCT features from baseline to 12 months. RESULTS: Individual PLs (110 in total) from 48 eyes (48 patients) showed at 12 months; 57/110 PLs (51.8%) were closed on indocyanine green angiography. At 12 months, eyes with closed PLs were more likely to have the following OCT features: 1) no subretinal fluid (67.1% vs. 32.9%), 2) smaller pigment epithelial detachment height (67.2 [±43.8] vs. 189.2 [±104.9] µm), 3) densely hyperreflective pigment epithelial detachment contents (84.0% vs. 16.0%), 4) an absence of a hyperreflective ring(64.0% vs. 36.0%), and a 5) indistinct overlying retinal pigment epithelial (71.4% vs. 28.6%) (all P < 0.05). The three highest performing OCT features that differentiated perfused from closed PLs were (1), (3), and (4) (area under the receiver operating characteristic curve 0.85, 0.73, and 0.70, respectively). A combination of these three features achieved an area under the receiver operating characteristic curve of 0.90. CONCLUSION: Polypoidal lesion closure, an important anatomical treatment outcome in polypoidal choroidal vasculopathy typically defined by indocyanine green angiography, can be accurately detected by specific OCT features.

Real-World Treatment Outcomes of Age-Related Macular Degeneration and Polypoidal Choroidal Vasculopathy in Asians.

PURPOSE: To describe the 12-month outcomes of treatment-naïve eyes with choroidal neovascularization (CNV) resulting from age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) after initiation of intravitreal anti-vascular endothelial growth factor (VEGF) monotherapy or combination therapy with verteporfin photodynamic therapy (PDT). DESIGN: A 12-month single-center, retrospective, comparative, nonrandomized cohort study. PARTICIPANTS: Patients with AMD or PCV who initiated intravitreal anti-VEGF therapy during 2015. METHODS: Demographics, visual outcomes, OCT, and treatment data were collected at baseline and months 1, 3, 6, and 12 after treatment initiation. Multivariate analysis was performed to identify baseline features predictive of visual maintenance and improvement after 12 months of treatment. MAIN OUTCOME MEASURES: Primary end point was visual acuity (VA) change from baseline to month 12. Secondary end points were treatment exposure and change in central subfield thickness on OCT. RESULTS: A total of 364 patients (165 AMD and 199 PCV) were included. Baseline vision was 41 and 43 logarithm of the minimum angle of resolution (logMAR) letters for AMD and PCV patients, respectively. Patients with AMD and PCV received 5.5 and 5.3 injections (5.0 monotherapy vs. 5.6 combination therapy; mean, 1.2 PDT sessions), respectively. Patients with AMD gained 4.7 logMAR letters after 12 months (P = 0.002), whereas PCV patients gained 6.6 logMAR letters (P = 0.001) and 10.8 logMAR letters (P < 0.001) for monotherapy and combination therapy, respectively. Only patients with presenting VA of fewer than 35 letters (Snellen equivalent, 6/60) achieved significant visual improvement (10.4 letters for AMD, 17.1 letters for PCV with monotherapy, and 35.5 letters for PCV with combination therapy). Predictors of VA gain included number of intravitreal injections (AMD and PCV adjusted odds ratio, 12.1 [P = 0.001] and 12.5 [P = 0.004] for ≥7 injections, respectively) and baseline VA of 20 logMAR letters or fewer (adjusted odds ratio, 3.8 and 10.6 for AMD and PCV, respectively). Age, gender, race, use of PDT or focal laser therapy, and central subfield thickness were not predictive of significant visual gain at 12 months. CONCLUSIONS: In Asian patients, treatment of AMD with anti-VEGF therapy yielded 12-month visual outcomes comparable with those of other real-world studies from Western populations but poorer than those of controlled trials. In contrast, for PCV eyes, anti-VEGF monotherapy and combination therapy with PDT yielded comparable outcomes as those of controlled clinical trials.

Shared Care for Patients with Diabetes at Risk of Retinopathy: A Feasibility Trial.

PURPOSE: While diabetes is a chronic disease, in many health care systems patients with diabetes at risk of diabetic retinopathy (DR) are managed in hospital settings. Aim of this feasibility study is to assess the quality of care and economic benefits of a shared care model managing patients at risk of DR in a primary eye care clinic (PEC) compared with a current tertiary specialist outpatient clinic (SOC). METHODS: A randomized trial was performed, to compare a PEC with a SOC in Singapore. The trial patients included those previously seen at the SOC, and having no DR or stable mild non proliferative (NPDR) with no macular edema, no visual and DR deterioration. Primary outcomes were clinical management. Secondary outcomes were patient satisfaction and cost of consultation. Differences analysis used equivalence testing and generalized odds ratios (GOR). RESULTS: The trial included 231 patients, 83.1% classified as no DR (PEC: 79.1%; SOC: 87.1%) and 16.9% as stable mild NPDR (PEC: 20.9%; SOC: 12.9%). DR management at PEC was significantly equivalent to that received at the SOC (rate difference 2.56%; CI: (-1.61% to 6.74%)) and 4.29%; CI: (0.14%-8.45%), respectively. Patient satisfaction at the PEC was equally high when compared to SOC (GOR: 1.71; CI: (0.50-2.00)). Direct costs per patient visit was 45% lower at PEC compared to SOC. CONCLUSIONS: Our feasibility trial showed that patients with diabetes with no or stable DR receive similar clinical care and management at a lower-cost PEC setting, are equally satisfied with the service compared to tertiary eye care. A follow-up study is necessary to validate these findings. Managing patients with diabetes at risk of DR at a PEC may be a safe and effective shared care model to improve accessibility for patients while enhancing professional collaboration between hospital and community settings.

ZIKA-RELATED MACULOPATHY.

PURPOSE: To report a case of unilateral maculopathy associated with acute Zika virus infection. METHODS: Observational case report of one patient. RESULTS: A 22-year-old man presented with acute blurring of vision 10 days after symptoms of Zika virus infection. Findings resembling unilateral acute idiopathic maculopathy of the right eye were noted on ophthalmoscopy, fluorescein angiography, indocyanine green angiography, and optical coherence tomography. Localized macular dysfunction in the right eye was noted on multifocal electroretinography. The left eye was normal. He was managed conservatively with resolution of symptoms in 3 weeks. CONCLUSION: We describe a case of unilateral acute idiopathic maculopathy-like disease in a patient with reverse transcriptase polymerase chain reaction-confirmed Zika virus infection.

IMPROVED DETECTION AND DIAGNOSIS OF POLYPOIDAL CHOROIDAL VASCULOPATHY USING A COMBINATION OF OPTICAL COHERENCE TOMOGRAPHY AND OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

PURPOSE: To assess the ability of optical coherence tomography (OCT) alone and in combination with OCT angiography (OCTA) to differentiate polypoidal choroidal vasculopathy (PCV) from neovascular age-related macular degeneration, as compared to fluorescein angiography and indocyanine green angiography. METHODS: This is a cross-sectional study. All participants had a standardized history, clinical examination including measurement of best-corrected visual acuity, slit-lamp biomicroscopy, and indirect fundus examination, and underwent standardized imaging (color photography, fluorescein and indocyanine green angiography, OCT, and OCTA) after predefined protocols. We used a 2-step approach (Step 1: spectral domain OCT; Step 2: addition of OCTA) combining structural OCT and OCTA to differentiate 50 treatment-naive eyes with PCV, choroidal neovascularization, and retinal angiomatous proliferation and compared with the diagnosis based on fluorescein angiography and indocyanine green angiography. Spectral domain OCT signs used to diagnose PCV included presence of two out of three of any retinal pigment epithelium detachment (pigment epithelial detachment/double-layer sign), notched or narrow-peaked pigment epithelial detachment, or round subretinal pigment epithelium structure. Optical coherence tomography angiography signs used to diagnose PCV included presence of a localized subretinal pigment epithelium hyperflow signal in the cross-sectional OCTA and/or presence of a focal hyperflow sign in en face OCTA based on outer retina slab. RESULTS: Based on fluorescein angiography and indocyanine green angiography, the diagnosis was choroidal neovascularization in 24 eyes, PCV in 23 eyes, and retinal angiomatous proliferation in 3 eyes. Based on spectral domain OCT signs, PCV was diagnosed in 19/23 (82.6%) eyes; however, specificity of OCT was only 51.9%. Cross-sectional OCTA showed a diffuse hyperflow signal in all 24 (100.0%) eyes with choroidal neovascularization, whereas a localized subretinal pigment epithelium hyperflow signal was detected in 19/23 (82.6%) eyes with PCV. En face OCTA only detected a nodular hyperflow signal in 10/23 eyes (43.5%) with PCV. Combination of OCT and OCTA achieved 82.6% sensitivity and 100.0% specificity for differentiating PCV from choroidal neovascularization/retinal angiomatous proliferation. CONCLUSION: Cross-sectional OCTA is more sensitive than en face OCTA in detecting flow signal in polyps. Combination of structural OCT and OCTA can be used to screen for PCV with a high level of sensitivity and specificity.

Human pharyngeal microbiota in age-related macular degeneration.

BACKGROUND: While the aetiology of age-related macular degeneration (AMD)-a major blinding disease-remains unknown, the disease is strongly associated with variants in the complement factor H (CFH) gene. CFH variants also confer susceptibility to invasive infection with several bacterial colonizers of the nasopharyngeal mucosa. This shared susceptibility locus implicates complement deregulation as a common disease mechanism, and suggests the possibility that microbial interactions with host complement may trigger AMD. In this study, we address this possibility by testing the hypothesis that AMD is associated with specific microbial colonization of the human nasopharynx. RESULTS: High-throughput Illumina sequencing of the V3-V6 region of the microbial 16S ribosomal RNA gene was used to comprehensively and accurately describe the human pharyngeal microbiome, at genus level, in 245 AMD patients and 386 controls. Based on mean and differential microbial abundance analyses, we determined an overview of the pharyngeal microbiota, as well as candidate genera (Prevotella and Gemella) suggesting an association towards AMD health and disease conditions. CONCLUSIONS: Utilizing an extensive study population from Singapore, our results provided an accurate description of the pharyngeal microbiota profiles in AMD health and disease conditions. Through identification of candidate genera that are different between conditions, we provide preliminary evidence for the existence of microbial triggers for AMD. Ethical approval for this study was obtained through the Singapore Health Clinical Institutional Review Board, reference numbers R799/63/2010 and 2010/585/A.

Incidence of Fellow Eye Involvement in Patients With Unilateral Exudative Age-Related Macular Degeneration.

Importance: Since the advent of optical coherence tomography angiography (OCT-A), nonexudative neovascularization has been described in the fellow eyes of unilateral exudative age-related macular degeneration (AMD). However, there is limited literature describing the natural course and optimal management of these lesions. Objective: To determine the incidence of fellow eye involvement in patients presenting with unilateral typical AMD or polypoidal choroidal vasculopathy and to evaluate the patterns of OCT-A changes within 6 months before the onset of exudative changes, especially focusing on nonexudative neovascularization. Design, Setting, and Participants: Data for this study were taken from a prospective, observational cohort study involving Asian patients with exudative AMD in the Asian AMD Phenotyping Study between October 2015 and March 2016. Analyses began in June 2017. Only patients who had gradable OCT-A and indocyanine green angiography (ICGA) scans of the fellow eye at baseline and follow-up at least 6 months apart were included for the analysis. The contralateral eye was evaluated for presence of nonexudative neovascularization based on multimodal imaging, which included ICGA, spectral domain optical coherence tomography, and OCT-A. Main Outcomes and Measures: The difference between the incidence of those with nonexudative choroidal neovascularization and those without as analyzed using log-rank test and qualitative analysis of OCT-A images. Results: We included 95 fellow eyes of 95 patients who presented with unilateral exudative AMD with a mean (SD) age of 68.6 (8.6) years. Nonexudative neovascularization was present in 18 eyes (19%) (8 [22.9%] and 10 [19.0%] fellow eyes with typical AMD and polypoidal choroidal vasculopathy, respectively; 8 [44.4%] on OCT-A; 5 [27.8%] on ICGA; and 5 [27.8%] on both OCT-A and ICGA). Development of exudative changes was noted in 6 fellow eyes (6.3%). Four eyes developed exudation from previously noted nonexudative neovascularization, and 2 eyes arose exudative changes from de novo. The probability of developing exudation within 6 months was significantly higher in eyes with baseline nonexudative neovascularization (0.087; 95% CI, 0.0033-0.210) compared with eyes without (0.010; 95% CI, 0.0026-0.041) (P = .008). In all eyes whose OCT-A images were available immediately before the onset of exudative changes, there was an increase in the size of network vessels compared with baseline. Conclusions and Relevance: The presence of nonexudative neovascularization may predispose to the development of exudative changes.

Change in vision-related quality of life and influencing factors in Asians receiving treatment for neovascular age-related macular degeneration.

AIM: To assess the change in vision-related quality of life (VRQoL) after treatment for neovascular age-related macular degeneration (nAMD) and factors influencing this change in an Asian population. METHODS: In this longitudinal study, 116 patients (mean age±SD=66.5±9.9 years; 59.5% male) who underwent treatment for nAMD were recruited from a tertiary eye centre in Singapore. Best-corrected visual acuity (BCVA) and the Impact of Vision Impairment (IVI) questionnaire were evaluated at baseline and month 12. We defined three categories of BCVA change in the treated eye: BCVA gain ≥2 lines; no change in BCVA; BCVA loss ≥2 lines. The main outcome measures were the Rasch-derived IVI Reading, Mobility, and Emotional Scores. Multivariable linear regression analyses assessed the influence of sociodemographic, clinical and treatment-related factors on change in VRQoL. RESULTS: Following treatment, mean treated-eye BCVA improved by almost 2 lines (-0.22±0.40 logMAR, p<0.001) and 43% (n=50) patients reported a gain in BCVA of ≥2 lines. Mean±SD scores for Reading, Mobility and Emotional demonstrated positive changes of 0.43±1.73, 0.45±1.54 and 0.66±1.6, respectively (p<0.001 for all). In multivariable models, a ≥2 line improvement in BCVA was independently associated with a 47% (ß=0.20; CI 0.01 to 0.39) increase in Reading Scores, but was not independently associated with Mobility or Emotional Scores. CONCLUSION: Nearly half of patients undergoing treatment for nAMD reported a 2-line improvement in vision which was, in turn, associated with substantial positive increases in Reading Scores. Improvements in Mobility and Emotional Scores appear to be driven by factors other than visual acuity.

CHOROIDAL VASCULAR HYPERPERMEABILITY AS A PREDICTOR OF TREATMENT RESPONSE FOR POLYPOIDAL CHOROIDAL VASCULOPATHY.

PURPOSE: To investigate the influence of choroidal vascular hyperpermeability (CVH) and choroidal thickness on treatment outcomes in eyes with polypoidal choroidal vasculopathy (PCV) undergoing anti-vascular endothelial growth factor monotherapy or combination therapy of photodynamic therapy and anti-vascular endothelial growth factor injections. METHODS: The authors performed a prospective, observational cohort study involving 72 eyes of 72 patients with polypoidal choroidal vasculopathy (mean age 68.6 years, 51% men) treated with either monotherapy (n = 41) or combination therapy (n = 31). Each eye was imaged with color fundus photography, fluorescent angiography, indocyanine green angiography, and spectral domain optical coherence tomography. Indocyanine green angiography images were used to evaluate CVH, and spectral domain optical coherence tomography was used to measure central choroidal thickness. Changes in visual acuity over 12 months, and number of anti-vascular endothelial growth factor injections were investigated. RESULTS: Choroidal vascular hyperpermeability was present in 31 eyes (43.1%). Visual acuity change over 12 months was numerically better in the CVH group compared with the CVH (-) group (-0.099 and -0.366 logarithm of the minimal angle of resolution unit in the CVH (-) and CVH (+) groups, respectively, multivariate P = 0.063) and significantly better in a matched pair analysis (P = 0.033). Furthermore, in the combination therapy group, the number of injection was significantly lower in the CVH (+) group compared with the CVH (-) group (4.68 vs. 2.58 injections/year in the CVH (-) and CVH (+) groups; P = 0.0044). There was no significant relationship between treatment response and choroidal thickening. CONCLUSION: The presence of CVH is associated with better visual outcome in eyes with polypoidal choroidal vasculopathy and lower injection number in combination therapy. Thus, CVH, but not choroidal thickness, should be further evaluated as a potential biomarker for selecting patients for combination therapy.

Shared Cared for Stable Glaucoma Patients: Economic Benefits and Patient-centered Outcomes of a Feasibility Trial.

PURPOSE: The purpose of this article is to assess the quality of care and economic benefits of a shared care model managing patients with stable glaucoma in a primary eye care (PEC) clinic compared with a tertiary specialist outpatient clinic (SOC) in Singapore. PATIENTS AND METHODS: A randomized equivalence feasibility trial was preformed comparing the PEC with SOC models. Participants recruited from the SOC had no visual field progression or change in management for at least 3 years, were on a maximum of a single glaucoma medication, had no previous tube-shunt implant and were at least 3-year posttrabeculectomy surgery.Primary outcomes were clinical assessment and management, economic benefits, and patient satisfaction. Differences were analyzed using equivalence testing and generalized odds ratios. RESULTS: The trial included 233 patients, consisting of 42.1% glaucoma disc suspects (PEC: 47.4%; SOC: 36.8%), 27.5% primary angle closure suspects (PEC: 25.0%; SOC: 29.9%), 13.7% with ocular hypertension (PEC: 13.8%; SOC: 13.7%), 3.9% with primary angle closure glaucoma (PEC: 4.3%; SOC: 3.4%), and 3.0% with primary open angle glaucoma (PEC: 1.7%; SOC: 4.3%). Glaucoma clinical care for patients at PEC was as good as SOC [rate difference, 6.83%; 95% confidence interval (CI), 2.84-11.12) and management (rate difference, 7.69%; 95% CI, 3.21-12.17). In 23 cases (9.9%), 5.2% at PEC and 14.5% at SOC, there was disconcordance with the gold standard of senior consultant. Patient satisfaction at the PEC was equally high when compared with SOC (generalized odds ratio, 1.43; CI, 0.50-2.00). Direct costs per patient visit were 43% lower at PEC compared with SOC. CONCLUSION: Managing stable glaucoma patients at a primary care setting is a cost saving, safe, and effective shared care while enhancing professional collaboration between hospital and community settings.

COMPARISON OF OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHIC CHANGES AFTER ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY ALONE OR IN COMBINATION WITH PHOTODYNAMIC THERAPY IN POLYPOIDAL CHOROIDAL VASCULOPATHY.

PURPOSE: To compare changes in optical coherence tomography angiography in eyes with polypoidal choroidal vasculopathy after treatment with anti-vascular endothelial growth factor monotherapy or combined with photodynamic therapy. METHODS: This is a longitudinal case-controlled study. The authors performed optical coherence tomography angiography at baseline and Month 3 in patients with treatment-naive polypoidal choroidal vasculopathy undergoing monotherapy (n = 10) or combination therapy (n = 13). We analyzed flow signal within the outer retina and choriocapillaris using automated segmentation. The authors analyzed the presence of pachyvessels using a 10.4-µm segment through Haller layer. The changes in each layer were compared between treatments. RESULTS: At Month 3, both groups showed similar improvement in best-corrected visual acuity and central retinal thickness. However, flow signal within the polypoidal choroidal vasculopathy complex was decreased in more eyes after combination therapy than after monotherapy (84.6% vs. 40.0%, P = 0.04). Patchy reduction in flow signal within the choriocapillaris layer was noted in 15.4% and 10.0% after combination therapy and monotherapy, respectively (P = 0.61). Significant reduction in pachyvessel caliber was seen only after combination therapy but not after monotherapy (75.0% vs. 0.0%, P = 0.01). CONCLUSION: Longitudinal optical coherence tomography angiography demonstrates more significant reduction in lesion flow and pachyvessels in the short term after combination therapy than after monotherapy, although visual and structural OCT showed similar improvement.