Ophthalmology (Eye & Ear Hospital) - Research Publications
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ItemAge-related macular degeneration (AMD): More than meets the eye. The role of multimodal imaging in today's management ofAMD-A review(WILEY, 2020-09)Multimodal imaging (MMI) allows a more granular grading of age-related macular degeneration (AMD) disease severity, with many novel risk factors having been recently identified. With this imaging information, we are better able to counsel our patients with more accurate and individualized progression scenarios. MMI also allows identification of anatomical features that increase our understanding of disease processes involved in progression to late AMD. Treatment protocols for neovascular AMD (nAMD) depend largely on the optical coherence tomography (OCT) appearance to determine disease activity, which allows us to individualize treatment. In geographic atrophy (GA), new intervention trials require the ability to define the extent of GA, so that GA growth rate can be determined. This is achieved through fundus autofluorescence (FAF) imaging, which allows greater accuracy of border identification, as well as revealing FAF patterns predictive of growth rates. As we strive to bring interventions earlier in the disease course, OCT imaging provides an ability to identify the first signs of atrophy, which may serve as novel surrogate biomarkers for GA, thereby facilitating trials. In the future, the use of artificial intelligence (AI) to automatically identify relevant features on MMI could further enhance our ability to determine disease severity, predict progression and assist in identifying disease activity parameters to support clinical decision making when treating nAMD. Newer developments may allow frequent, remote capturing of images, reducing clinic visits, detecting progression and monitoring neovascular activity in-between clinic visits. Being aware of these new imaging insights in AMD, greatly enhance our clinical management of AMD.
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ItemMulti-focal electro-retinogram response following sub-threshold nano-second laser intervention in age-related macular degeneration(WILEY, 2020-09)IMPORTANCE: The effect of sub-threshold nano-second laser (SNL) treatment on retinal function remains unknown. BACKGROUND: SNL treatment has been studied as a potential intervention in intermediate age-related macular degeneration (iAMD). This study investigated the longitudinal effect of SNL treatment on retinal function. DESIGN: This was a sub-study of the LEAD trial; a 36-month, multi-centre, randomized and sham-controlled trial. PARTICIPANTS: Subjects with iAMD. METHODS: Eligible participants were assigned randomly to receive SNL or sham treatment to the study eye at 6-monthly visits. Multi-focal electro-retinography (mfERG) was performed at each study visit from a study site. The mfERG responses were grouped into three regions (central, middle and outer rings) and compared between the SNL and sham group. MAIN OUTCOME MEASURES: mfERG P1 response amplitude and implicit time. RESULTS: Data were collected from 50 subjects (26 in the SNL group, 24 in the sham group). At baseline, the P1 amplitudes of both the study eyes and the fellow eyes were similar between the groups at all rings. In the sham group, the P1 amplitude gradually decreased over time (P < .05). In the SNL group, there was an improvement in P1 amplitude which became statistically significant at the 36-month visit, detected in both the treated and fellow eyes at the central (P = .005) and middle ring (P = .007) but not at the outer ring (P = .070). No difference in P1 implicit time detected between the groups (P > .05). CONCLUSIONS AND RELEVANCE: SNL treatment improved electro-physiological function. mfERG could be useful for monitoring AMD progression and evaluating the efficacy of SNL treatment.
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ItemNo Preview AvailableIncomplete Retinal Pigment Epithelial and Outer Retinal Atrophy in Age-Related Macular Degeneration Classification of Atrophy Meeting Report 4(ELSEVIER SCIENCE INC, 2020-03)PURPOSE: To describe the defining features of incomplete retinal pigment epithelium (RPE) and outer retinal atrophy (iRORA), a consensus term referring to the OCT-based anatomic changes often identified before the development of complete RPE and outer retinal atrophy (cRORA) in age-related macular degeneration (AMD). We provide descriptive OCT and histologic examples of disease progression. DESIGN: Consensus meeting. PARTICIPANTS: Panel of retina specialists, including retinal imaging experts, reading center leaders, and retinal histologists. METHODS: As part of the Classification of Atrophy Meeting (CAM) program, an international group of experts analyzed and discussed longitudinal multimodal imaging of eyes with AMD. Consensus was reached on a classification system for OCT-based structural alterations that occurred before the development of atrophy secondary to AMD. New terms of iRORA and cRORA were defined. This report describes in detail the CAM consensus on iRORA. MAIN OUTCOME MEASURES: Defining the term iRORA through OCT imaging and longitudinal cases showing progression of atrophy, with histologic correlates. RESULTS: OCT was used in cases of early and intermediate AMD as the base imaging method to identify cases of iRORA. In the context of drusen, iRORA is defined on OCT as (1) a region of signal hypertransmission into the choroid, (2) a corresponding zone of attenuation or disruption of the RPE, and (3) evidence of overlying photoreceptor degeneration. The term iRORA should not be used when there is an RPE tear. Longitudinal studies confirmed the concept of progression from iRORA to cRORA. CONCLUSIONS: An international consensus classification for OCT-defined anatomic features of iRORA are described and examples of longitudinal progression to cRORA are provided. The ability to identify these OCT changes reproducibly is essential to understand better the natural history of the disease, to identify high-risk signs of progression, and to study early interventions. Longitudinal data are required to quantify the implied risk of vision loss associated with these terms. The CAM classification provides initial definitions to enable these future endeavors, acknowledging that the classification will be refined as new data are generated.
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ItemBaseline characteristics and age-related macular degeneration in participants of the "ASPirin in Reducing Events in the Elderly" (ASPREE)-AMD trial(ELSEVIER INC, 2020-12)PURPOSE: To describe the baseline participant characteristics in the ASPREE-AMD study, investigating the effect of aspirin on AMD incidence and progression. METHODS: Australian participants from the ASPirin in Reducing Events in the Elderly (ASPREE) trial, randomized to 100 mg aspirin daily or placebo, had non-mydriatic, digital color fundus images graded according to the Beckman AMD classification. Associations with AMD were determined for baseline characteristics and genetic risk variants. RESULTS: ASPREE-AMD sub-study enrolled 4993 participants with gradable macular images. Median age was 73.4 years (IQR, 71.5, 76.6), 52% were female, 10% had diabetes mellitus, 73% had hypertension, and 44% were former/current smokers. Early, intermediate and late AMD (detected in 20.6%, 16.1%, 1.1%, respectively), significantly associated with age, were also associated with increasing HDL levels: OR = 1.52 (95%CI, 1.26, 1.84), OR = 1.43 (1.17, 1.77) and OR = 1.96 (1.02, 3.76), respectively. Female sex was associated with early [OR = 1.37 (1.16, 1.62)], and intermediate [OR = 1.35 (1.12, 1.63)] AMD, as was previous regular use of aspirin, with OR = 1.46 (1.11, 1.92) and OR = 1.37 (1.01, 1.85), respectively. Current smoking had increased odds for late AMD, OR = 4.02 (1.42, 11.36). Genetic risk variant rs3750846 (ARMS2/HTRA1) was associated with each AMD stage (p < 0.001), risk variants rs570618 and rs10922109 (CFH) with intermediate and late AMD (p < 0.001), and rare variant rs147859257 (C3) with late AMD (p < 0.001). The randomized groups were well balanced for all analyzed AMD risk factors. CONCLUSIONS: Observed associations are typical of AMD. The ASPREE-AMD clinical trial provides a unique opportunity to determine the risks and benefits of low-dose aspirin for AMD incidence and progression in elderly population. TRIAL REGISTRATION: Australian New Zealand Clinical Trial Registry: ACTRN 12613000755730.
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ItemArtificial Intelligence Algorithms for Analysis of Geographic Atrophy: A Review and Evaluation(ASSOC RESEARCH VISION OPHTHALMOLOGY INC, 2020-01)PURPOSE: The purpose of this study was to summarize and evaluate artificial intelligence (AI) algorithms used in geographic atrophy (GA) diagnostic processes (e.g. isolating lesions or disease progression). METHODS: The search strategy and selection of publications were both conducted in accordance with the Preferred of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed and Web of Science were used to extract literary data. The algorithms were summarized by objective, performance, and scope of coverage of GA diagnosis (e.g. lesion automation and GA progression). RESULTS: Twenty-seven studies were identified for this review. A total of 18 publications focused on lesion segmentation only, 2 were designed to detect and classify GA, 2 were designed to predict future overall GA progression, 3 focused on prediction of future spatial GA progression, and 2 focused on prediction of visual function in GA. GA-related algorithms reported sensitivities from 0.47 to 0.98, specificities from 0.73 to 0.99, accuracies from 0.42 to 0.995, and Dice coefficients from 0.66 to 0.89. CONCLUSIONS: Current GA-AI publications have a predominant focus on lesion segmentation and a minor focus on classification and progression analysis. AI could be applied to other facets of GA diagnoses, such as understanding the role of hyperfluorescent areas in GA. Using AI for GA has several advantages, including improved diagnostic accuracy and faster processing speeds. TRANSLATIONAL RELEVANCE: AI can be used to quantify GA lesions and therefore allows one to impute visual function and quality-of-life. However, there is a need for the development of reliable and objective models and software to predict the rate of GA progression and to quantify improvements due to interventions.
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ItemValidation of an Automated Quantification of Relative Ellipsoid Zone Reflectivity on Spectral Domain-Optical Coherence Tomography Images(ASSOC RESEARCH VISION OPHTHALMOLOGY INC, 2020-10)PURPOSE: Relative ellipsoid zone reflectivity (rEZR) represents a potential biomarker of photoreceptor health on spectral-domain optical coherence tomography (SD-OCT). Because manual quantification of rEZR is laborious and lacks of spatial resolution, automated quantification of the rEZR would be beneficial. The purpose of this study was to evaluate the reliability and reproducibility of an automated rEZR quantification method. METHODS: The rEZR was acquired using a manual and an automated approach in eyes with age-related macular degeneration (AMD) and healthy controls. The rEZR obtained from both methods was compared and the agreement between the methods and their reproducibility assessed. RESULTS: Forty eyes of 40 participants with a mean (± standard deviation) age of 65.2 ± 7.8 years were included. Both the manual and automated method showed that control eyes exhibit a greater rEZR than AMD eyes (P < 0.001). Overall, the limits of agreement between the manual and automated method were -7.5 to 7.3 arbitrary units (AU) and 95% of the data points had a difference in the rEZR between the methods of ±8.2%. An expected perfect reproducibility was observed for the automated method, whereas the manual method had a coefficient of repeatability of 6.3 arbitrary units. CONCLUSIONS: The automated quantification of rEZR method is reliable and reproducible. Further studies of the rEZR as a novel biomarker for AMD severity and progression are warranted. TRANSLATIONAL RELEVANCE: Automated quantification of SD-OCT-based rEZR allows for its comprehensive and longitudinal characterization evaluating its relevance as an in vivo biomarker of photoreceptor function and its prognostic value for AMD progression.
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ItemAnti-Vascular Endothelial Growth Factor Use and Atrophy in Neovascular Age-Related Macular Degeneration Systematic Literature Review and Expert Opinion(ELSEVIER SCIENCE INC, 2020-05)TOPIC: To summarize the rates of atrophy, risk factors, and atrophy-associated visual outcomes in patients with neovascular age-related macular degeneration (nAMD) who received anti-vascular endothelial growth factor (VEGF) treatment for macular neovascularization (MNV). CLINICAL RELEVANCE: Age-related macular degeneration is a leading cause of vision loss worldwide, and VEGF inhibitors are the primary treatment for nAMD. However, atrophy is observed frequently in eyes treated with anti-VEGF therapy, prompting questions regarding a causative role for these therapies in atrophy development. METHODS: PubMed was searched for articles published in the past 5 years (January 1, 2014, through January 10, 2019). Studies including atrophy outcome(s) in patients with age-related macular degeneration who received anti-VEGF treatment were included. Review articles, retrospective studies, case reports or studies, preclinical studies, prevalence data reports, and non-English studies were excluded. Randomization was not required. RESULTS: Overall, 145 studies were identified; 29 publications were included, with cohorts ranging from 8 to 1185 eyes. Imaging methods used to assess atrophy varied across studies. All studies confirmed the occurrence of atrophy, and when available, longitudinal data from the included studies demonstrated an increase in atrophy incidence over time. Key risk factors or phenotypes associated with atrophy were fellow eye atrophy, reticular pseudodrusen, increased injections, and type 3 lesion. In addition, visual acuity loss was noted with foveal atrophy. DISCUSSION: All studies demonstrated that atrophy occurs in the context of MNV treated with anti-VEGF therapy; however, it is not clear whether anti-VEGF treatment is causative of atrophy versus being associated with atrophy development. The included studies were not designed or powered to assess atrophy as a primary outcome. In addition, it is difficult to determine whether prognostic factors directly affect atrophy. Furthermore, patient populations in clinical trials do not necessarily represent real-world patients. Although phenotypes and risk factors may help to identify those at greater risk of atrophy developing, it is important to recognize that adequately treating exudative MNV remains the best option to optimize vision outcomes in patients with nAMD, particularly given the risk of vision loss with undertreatment observed in the real world.
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ItemConsensus Nomenclature for Reporting Neovascular Age-Related Macular Degeneration Data Consensus on Neovascular Age-Related Macular Degeneration Nomenclature Study Group(ELSEVIER SCIENCE INC, 2020-05)PURPOSE: To establish a process to evaluate and standardize a state-of-the-art nomenclature for reporting neovascular age-related macular degeneration (AMD) data. DESIGN: Consensus meeting. PARTICIPANTS: An international panel of retina specialists, imaging and image reading center experts, and ocular pathologists. METHODS: During several meetings organized under the auspices of the Macula Society, an international study group discussed and codified a set nomenclature framework for classifying the subtypes of neovascular AMD and associated lesion components. MAIN OUTCOME MEASURES: A consensus classification of neovascular AMD. RESULTS: The study group created a standardized working definition of AMD. The components of neovascular AMD were defined and subclassified. Disease consequences of macular neovascularization were delineated. CONCLUSIONS: The framework of a consensus nomenclature system, a definition of AMD, and a delineation of the subtypes of neovascular AMD were developed. Establishing a uniform set of definitions will facilitate comparison of diverse patient groups and different studies. The framework presented is modified and updated readily, processes that are anticipated to occur on a periodic basis. The study group suggests that the consensus standards outlined in this article be used in future reported studies of neovascular AMD and clinical practice.
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ItemMacular Atrophy in Neovascular Age-Related Macular Degeneration A Randomized Clinical Trial Comparing Ranibizumab and Aflibercept (RIVAL Study)(ELSEVIER SCIENCE INC, 2020-02)PURPOSE: To investigate differences in the development of macular atrophy (MA) over 24 months between treat-and-extend (T&E) ranibizumab and aflibercept in patients with neovascular age-related macular degeneration (nAMD). DESIGN: A phase 4 randomized, partially masked, multicenter study. PARTICIPANTS: Individuals 50 years of age or older diagnosed with active, treatment-naïve subfoveal choroidal neovascularization secondary to nAMD with baseline best-corrected visual acuity (BCVA) of 23 logarithm of minimum angle of resolution letters or more. METHODS: Patients were randomized 1:1 to receive either intravitreal injections of ranibizumab 0.5 mg or aflibercept 2.0 mg and were treated according to the same reading center-guided T&E regimen after 3 initial monthly injections. MAIN OUTCOME MEASURES: The primary outcome was mean change in square root area of MA from baseline to month 24. Key secondary outcomes included number of injections and mean change in BCVA from baseline to months 12 and 24. RESULTS: Two hundred seventy-eight patients were included in the analysis (ranibizumab 0.5 mg, n = 141; aflibercept 2.0 mg, n = 137). Mean change in square root area of MA from baseline to month 24 was +0.36 mm (95% confidence interval [CI], 0.27-0.45 mm) for ranibizumab and +0.28 mm (95% CI, 0.19-0.37 mm) for aflibercept (treatment difference, +0.08 mm [95% CI, -0.05 to 0.21 mm]; P = 0.24). The proportion of patients with MA increased from 7% (10/141) to 37% (43/117) for ranibizumab and from 6% (8/137) to 32% (35/108) for aflibercept from baseline to month 24. The average number of injections received per year was similar between both groups: 9.6 (95% CI, 9.2-10.0) for ranibizumab and 9.5 (95% CI, 9.1-9.9) for aflibercept. The mean change in BCVA from baseline to month 24 was +6.6 letters (95% CI,4.7-8.5 letters) for the ranibizumab group and +4.6 letters (95% CI, 2.7-6.6 letters) for the aflibercept group ( P = 0.15). Rates of adverse events (AEs) were similar between both groups. CONCLUSIONS: No significant differences in the rate of development or growth of MA over 24 months were observed between ranibizumab and aflibercept in nAMD patients treated using an identical T&E regimen.
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ItemA transcriptome-wide association study based on 27 tissues identifies 106 genes potentially relevant for disease pathology in age-related macular degeneration(NATURE PORTFOLIO, 2020-01-31)Genome-wide association studies (GWAS) for late stage age-related macular degeneration (AMD) have identified 52 independent genetic variants with genome-wide significance at 34 genomic loci. Typically, such an approach rarely results in the identification of functional variants implicating a defined gene in the disease process. We now performed a transcriptome-wide association study (TWAS) allowing the prediction of effects of AMD-associated genetic variants on gene expression. The TWAS was based on the genotypes of 16,144 late-stage AMD cases and 17,832 healthy controls, and gene expression was imputed for 27 different human tissues which were obtained from 134 to 421 individuals. A linear regression model including each individuals imputed gene expression data and the respective AMD status identified 106 genes significantly associated to AMD variants in at least one tissue (Q-value < 0.001). Gene enrichment analysis highlighted rather systemic than tissue- or cell-specific processes. Remarkably, 31 of the 106 genes overlapped with significant GWAS signals of other complex traits and diseases, such as neurological or autoimmune conditions. Taken together, our study highlights the fact that expression of genes associated with AMD is not restricted to retinal tissue as could be expected for an eye disease of the posterior pole, but instead is rather ubiquitous suggesting processes underlying AMD pathology to be of systemic nature.