Phenotype and genotype characteristics of age-related macular degeneration in a Japanese population

Efficacy, durability, and safety of faricimab up to every 16 weeks in patients with neovascular age-related macular degeneration: 2-year results from the Japan subgroup of the phase III TENAYA trial

PURPOSE

To evaluate 2-year efficacy, durability, and safety of faricimab in the TENAYA Japan subgroup and pooled global TENAYA/LUCERNE cohort of patients with neovascular age-related macular degeneration (nAMD).

METHODS

Subgroup analysis of TENAYA/LUCERNE (NCT03823287/NCT03823300): phase III, multicentre, randomised, active comparator-controlled, double-masked, non-inferiority trials. Treatment-naïve patients aged ≥ 50 years with nAMD were randomised (1:1) to intravitreal faricimab (6.0 mg up to every 16 weeks [Q16W] after 4 initial Q4W doses) or aflibercept (2.0 mg Q8W after 3 initial Q4W doses). Outcomes were assessed through year 2 for the TENAYA Japan subgroup (N = 133) and global pooled TENAYA/LUCERNE cohort (N = 1329).

RESULTS

Vision and anatomic improvements achieved with faricimab at year 1 were maintained over 2 years and were generally comparable between the TENAYA Japan subgroup and pooled TENAYA/LUCERNE cohort. Adjusted mean best-corrected visual acuity (BCVA) change from baseline at year 2 for the TENAYA Japan subgroup and global pooled TENAYA/LUCERNE cohort was +7.1 (3.7-10.5) and +4.4 (3.2-5.5) letters in the faricimab arm, respectively, and +5.2 (1.9-8.6) and +4.3 (3.1-5.4) letters in the aflibercept arm, respectively. At week 112, the proportion of faricimab-treated patients on Q16W dosing was 61.0% and 63.1% in the TENAYA Japan subgroup and pooled TENAYA/LUCERNE cohort. Faricimab was well tolerated through year 2.

CONCLUSION

Year 2 TENAYA Japan subgroup findings for faricimab were generally consistent with the pooled global TENAYA/LUCERNE results in patients with nAMD. Vision and anatomical benefits with faricimab were similar to those with aflibercept but with fewer injections.

Exudative Age-Related Macular Degeneration: Association between Treatment Efficacy and Single-Nucleotide Variants in RAD51B, TRIB1, COL8A1, COL10A1, IL-9, IL-10, and VEGFA Genes

Age-related macular degeneration (AMD) is a progressive neurodegenerative condition leading to vision loss and eventual blindness, with exudative AMD posing a heightened risk due to choroidal neovascularization and localized edema. Therapies targeting the VEGF pathway aim to address this mechanism for treatment effectiveness. Our study aimed to evaluate associations between specific genetic variants (RAD51B rs8017304, rs2588809; TRIB1 rs6987702, rs4351379; COL8A1 rs13095226; COL10A1 rs1064583; IL-9 rs1859430, rs2069870, rs11741137, rs2069885, rs2069884; IL-10 rs1800871, rs1800872, rs1800896; VEGFA rs1570360, rs699947, rs3025033, rs2146323) and the response to anti-VEGF treatment for exudative AMD. We enrolled 119 patients with exudative AMD categorized as responders or non-responders based on their response to anti-VEGF treatment. Statistical analysis revealed that RAD51B rs8017304 heterozygous and homozygous minor allele carriers had increased CMT before treatment compared to wild-type genotype carriers (p = 0.004). Additionally, TRIB1 rs4351379 heterozygous and homozygous minor allele carriers exhibited a greater decrease in central macular thickness (CMT) after 6 months of treatment than wild-type genotype carriers (p = 0.030). IL-9 rs1859430, rs2069870, and rs2069884 heterozygous and homozygous minor allele carriers had worse BCVA before treatment than wild-type genotype carriers (p = 0.018, p = 0.012, p = 0.041, respectively). Conversely, IL-9 rs2069885 heterozygous and homozygous minor allele carriers showed greater improvement in BCVA after 6 months compared to wild-type genotype carriers (p = 0.032). Furthermore, VEGFA rs699947 heterozygous and homozygous minor allele carriers had better BCVA before treatment and after 3 and 6 months of treatment than wild-type genotype carriers (p = 0.003, p = 0.022, respectively), with these carriers also exhibiting higher CMT after 6 months of anti-VEGF treatment (p = 0.032). Not all results remained statistically significant under this stringent correction for multiple comparisons. The comparisons of the serum concentrations of IL-10, VEGF-A, and VEGF-R2/KDR between non-responders and responders did not yield statistically significant differences. Our study identified significant associations between genetic variants, including RAD51B rs8017304, TRIB1 rs4351379, IL-9 rs1859430, rs2069870, rs2069884, rs2069885, and VEGFA rs699947, and parameters related to the efficacy of exudative AMD treatment, such as BCVA and CMT.

Efficacy of Brolucizumab in Polyp Regression of Treatment-Naive Polypoidal Choroidal Vasculopathy and Its Effect on 1-Year Treatment Outcome

PURPOSE

To evaluate the efficacy of intravitreal brolucizumab in polyp regression of treatment-naive polypoidal choroidal vasculopathy (PCV) patients and its effect on 1-year treatment outcome.

METHODS

Medical records of 31 treatment-naive PCV patients, who received three monthly intravitreal brolucizumab injections followed by as-needed injections for at least a year, were retrospectively reviewed. Visual and anatomical outcomes were evaluated at 3, 6, and 12 months. Complete polyp regression rate and percentage change of vascular lesion and polyp area were evaluated after three monthly injections of brolucizumab. The effect of complete polyp regression and the impact of vascular lesion and polyp reduction rate on 1-year treatment outcome were also evaluated.

RESULTS

In terms of visual outcome, best-corrected visual acuity significantly improved after 12-month follow-up (p < 0.001). In terms of anatomical outcome, central macular thickness (CMT) and central choroidal thickness significantly decreased after 12-month follow-up (p < 0.001). Complete polyp regression was observed in 23 patients (74.2%) after three monthly injections. Group with complete polyp regression had a higher rate of achieving dry macula at 3 months (p = 0.026) and fewer number of injections (p < 0.001) compared to the group without complete polyp regression. Higher polyp reduction rate was significantly associated with higher CMT change from baseline at 3 months (p = 0.048) while higher vascular lesion reduction rate was significantly associated with higher CMT change from baseline at 12 months (p = 0.031) and fewer number of injections (p = 0.012).

CONCLUSIONS

Intravitreal brolucizumab injection effectively improved visual and anatomical outcomes and achieved significant polyp regression in treatment-naive PCV patients. Complete polyp regression and the reduction rate of vascular lesion size and polyp size after loading injection significantly influence the treatment outcome of PCV patients. However, careful monitoring and preoperative warning is warranted due to occurrence of brolucizumab-related IOI.

Clinical variations of polypoidal choroidal vasculopathy: A cohort study from Japan and the USA

We describe the clinical characteristics of treatment-naïve polypoidal choroidal vasculopathy (PCV) in three tertiary clinic settings in 2 cities (Chicago in the USA and Nishinomiya in Japan). This cohort study was a retrospective, multicenter, consecutive case series. A total of 126 patients with treatment-naïve PCV-46 in Chicago and 80 in Nishinomiya-were identified. The proportion of PCV in patients with neovascular age-related macular degeneration was lower in Chicago (10.8% vs. 36.9%). Patients in Chicago had a significantly higher prevalence of soft drusen (50.0% vs 25.0%, p = 0.006) and intra-retinal cyst (37.0% vs 15.0%, p = 0.008), and a significantly lower prevalence of pachyvessels (41.3% vs 62.5%, p = 0.03). At baseline, presenting vision for patients in Chicago was worse than in Nishinomiya (mean log MAR: 0.609 vs. 0.312, p < 0.001). Ninety-five eyes were followed for more than one year. The Nishinomiya group received a higher rate of combination therapy (61.0%) compared to the Chicago group (5.3%). Vision and central foveal thickness at month 12 were significantly improved from baseline in both Chicago (p = 0.009 and p = 0.01) and Nishinomiya groups (both p < 0.001). Our study highlights interesting differences in the proportion of PCV, clinical findings and treatment responses of PCV, that need to be further evaluated in larger, epidemiologic cohorts.

Electrically-evoked responses for retinal prostheses are differentially altered depending on ganglion cell types in outer retinal neurodegeneration caused by Crb1 gene mutation

Background

Microelectronic prostheses for artificial vision stimulate neurons surviving outer retinal neurodegeneration such as retinitis pigmentosa (RP). Yet, the quality of prosthetic vision substantially varies across subjects, maybe due to different levels of retinal degeneration and/or distinct genotypes. Although the RP genotypes are remarkably diverse, prosthetic studies have primarily used retinal degeneration (rd) 1 and 10 mice, which both have Pde6b gene mutation. Here, we report the electric responses arising in retinal ganglion cells (RGCs) of the rd8 mouse model which has Crb1 mutation.

Methods

We first investigated age-dependent histological changes of wild-type (wt), rd8, and rd10 mice retinas by H&E staining. Then, we used cell-attached patch clamping to record spiking responses of ON, OFF and direction selective (DS) types of RGCs to a 4-ms-long electric pulse. The electric responses of rd8 RGCs were analyzed in comparison with those of wt RGCs in terms of individual RGC spiking patterns, populational characteristics, and spiking consistency across trials.

Results

In the histological examination, the rd8 mice showed partial retinal foldings, but the outer nuclear layer thicknesses remained comparable to those of the wt mice, indicating the early-stage of RP. Although spiking patterns of each RGC type seemed similar to those of the wt retinas, correlation levels between electric vs. light response features were different across the two mouse models. For example, in comparisons between light vs. electric response magnitudes, ON/OFF RGCs of the rd8 mice showed the same/opposite correlation polarity with those of wt mice, respectively. Also, the electric response spike counts of DS RGCs in the rd8 retinas showed a positive correlation with their direction selectivity indices (r = 0.40), while those of the wt retinas were negatively correlated (r = -0.90). Lastly, the spiking timing consistencies of late responses were largely decreased in both ON and OFF RGCs in the rd8 than the wt retinas, whereas no significant difference was found across DS RGCs of the two models.

Conclusion

Our results indicate the electric response features are altered depending on RGC types even from the early-stage RP caused by Crb1 mutation. Given the various degeneration patterns depending on mutation genes, our study suggests the importance of both genotype- and RGC type-dependent analyses for retinal prosthetic research.

Risk factors and clinical significance of prechoroidal cleft in eyes with neovascular age-related macular degeneration in Caucasian patients

OBJECTIVE

The objective of the study was to investigate the prevalence, risk factors and clinical significance of prechoroidal cleft (PC) among neovascular age-related macular degeneration (nAMD) patients in a Caucasian population.

DESIGN

A retrospective observational cohort study.

METHODS

A total of 140 patients with naive nAMD were treated with anti-vascular endothelial growth factor (VEGF) injections and a follow-up of ≥24 months. Optical coherence tomography (OCT) scans were graded for the presence of PC, central subfield foveal thickness (CSFT), maximal retinal thickness (MRT), pigment epithelial detachment (PED), presence of intraretinal fluid (IRF), subretinal fluid (SRF) and subretinal hyper-reflective material (SHRM) at baseline, 3, 6, 12 and 24 months. Best corrected visual acuity (BCVA) and anti-VEGF treatments were recorded.

RESULTS

Out of 140, 21 eyes (15%) developed PC. BCVA improved significantly from 0.68 ± 0.56 to 0.62 ± 0.59 logMAR after 24 months (p = 0.008). The change in BCVA was not related to the presence of cleft (p = 0.208). Multivariate analysis confirmed that higher baseline CSFT (p = 0.011, OR = 1.004, 95%, CI 1.001-1.007) and the presence of multi-layered PED (p < 0.001, OR = 21.153, 95%, CI 5.591-80.026) were both predictive for development of PC. Eyes with PC received more injections than eyes without PC.

CONCLUSION

Prechoroidal cleft was found in 15% of Caucasian nAMD patients treated with anti-VEGF injections and was related to greater retinal and PED height, as well as presence of multi-layered PED. Eyes with PC required more anti-VEGF injections. The presence of PC correlates with disease activity, and intensive anti-VEGF suppression can preserve vision.

VEGFA Haplotype and VEGF-A and VEGF-R2 Protein Associations with Exudative Age-Related Macular Degeneration

Our study aimed to reveal the associations between VEGFA SNPs (rs1570360, rs699947, rs3025033, and rs2146323), their haplotypes, VEGF-A and VEGF-R2 serum concentrations, and early and exudative AMD. A total of 339 subjects with early AMD and 419 with exudative AMD groups, and 374 healthy subjects, were genotyped for four VEGFA SNPs (rs1570360, rs699947, rs3025033, and rs2146323). VEGF-A and VEGFR-2 serum concentrations were measured in exudative AMD and controls. The results revealed that rs3025033 G allele was significantly associated with lower odds of exudative AMD under the dominant model (OR = 0.67; 95% CI: 0.49–0.80; p = 0.0088) and additive (OR = 0.7; 95% CI: 0.54–0.90; p = 0.0058) models after Bonferroni correction. In the female group, rs3025033 AG genotype was associated with exudative AMD under the codominant model (OR = 0.57; 95% CI: 0.37–0.87; p = 0.009) and G allele under the dominant (OR = 0.55; 95% CI: 0.37–0.82; p = 0.0032) and additive models (OR = 0.60; 95% CI: 0.42–0.84; p = 0.0028). Haplotype analysis revealed that individuals carrying rs1570360, rs699947, rs3025033, and rs2146323 haplotype A-A-G-A had decreased risk of exudative AMD (OR = 0.46, 95% CI: 0.23–0.90; p = 0.023). The VEGF-A and VEGF-R2 serum concentrations did not differ between study groups; we found that patients with exudative AMD carrying at least one C allele at rs699947 have statistically significantly higher VEGF-A serum concentrations compared to AA genotype carriers (485.95 (945.93) vs. 194.97 (-), respectively, p = 0.046). In conclusion, we found that VEGFA rs3025033 and haplotype rs1570360A-rs699947A-rs3025033G- rs2146323A play a protective role for exudative AMD in the Caucasian population. Furthermore, rs699947 is associated with elevated VEGF-A serum concentrations in exudative AMD.

Association of Dietary Nutrient Intake with Early Age-Related Macular Degeneration in Japanese-Americans

Lifestyle factors may be associated with the development of age-related macular degeneration (AMD), in addition to demographic and genetic factors. The purpose of this cross-sectional study is to elucidate the association between nutrient intake and AMD in the Japanese-American population living in Los Angeles. We conducted a medical survey of Japanese immigrants and their descendants living in Los Angeles, including interviews on dietary habits, fundus photography, and physical examinations. Participants were classified into early AMD and control groups on the basis of fundus photographic findings. Consequently, among the 555 participants, 111 (20.0%) were diagnosed with early AMD. There were no late-stage AMD participants. Multivariate logistic regression analysis showed that the intake of animal fat and saturated fatty acids (SFA) was positively associated with early AMD (p for trend = 0.01 for animal fat, p for trend = 0.02 for SFA), and the intake of vegetable fat, total carbohydrate, simple carbohydrate, sugar, and fructose was inversely associated with early AMD (p for trend = 0.04 for vegetable fat, p for trend = 0.046 for carbohydrate, p for trend = 0.03 for simple carbohydrate, p for trend = 0.046 for sugar, p for trend = 0.02). Our findings suggest that excessive animal fat and SFA intake increases the risk for early AMD in Japanese-Americans whose lifestyles have been westernized.

Pachychoroid spectrum disease

Recent improvements in ophthalmic imaging have led to the identification of a thickened choroid or pachychoroid to be associated with a number of retinal diseases. The number of conditions linked to this phenotype has continued to widen with specific endophenotypes found within the pachychoroid spectrum. The spectrum includes choroidal features such as focal or diffuse choroidal thickening and thinning of the overlying inner choroid, and choroidal hyperpermeability as demonstrated by indocyanine green angiography. In addition, these diseases are associated with overlying retinal pigmentary changes and retinal pigment epithelial dysfunction and may also be associated with choroidal neovascularization. This article provides a comprehensive review of the literature looking at diseases currently described within the pachychoroid spectrum including central serous chorioretinopathy, pachychoroid pigment epitheliopathy, pachychoroid neovasculopathy, polypoidal choroidal vasculopathy/aneurysmal type 1 neovascularization, peripapillary pachychoroid disease and focal choroidal excavation. We particularly focus on clinical imaging, genetics and pathological findings in these conditions with the aim of updating evidence suggesting a common aetiology between diseases within the pachychoroid spectrum.

Comparison of visual outcomes between therapy choices and subtypes of polypoidal choroidal vasculopathy (PCV) in Taiwan: a real-world study

Polypoidal choroidal vasculopathy (PCV) is a distinctive type of neovascular age-related macular degeneration prevalent in many Asian countries. However, there is still some controversy in how the subtypes of PCV are classified. This post-hoc study redefined the branching vascular network (BVN) and PCV subtypes through retrospective review of indocyanine green angiography (ICGA) and fluorescein angiography images from two observational studies (RENOWNED/REAL). Of the visual outcomes for each angiographic subtype and treatment pattern investigated, BVN was identified in 56.3% of PCV patients. The proportions and features of the re-defined PCV subtypes were 43.8%, 10.4%, and 45.8% for subtype A (without distinctive features of BVN), B (with BVN but no leakage), and C (with BVN and leakage), respectively. Subtype A had better visual outcomes when compared to subtype C. This possibly resulted from a better baseline visual acuity in subtype A. Moreover, combination therapy [photodynamic therapy plus anti-vascular endothelial growth factor (VEGF)] may lead to better visual improvement than mono-anti-VEGF treatment alone. This study provides the prevalence of PCV subtypes in Taiwan and may serve as a reference for PCV treatment strategies in a real-world setting, especially for the combination therapy and patients without distinctive features of BVN.

Deep phenotype unsupervised machine learning revealed the significance of pachychoroid features in etiology and visual prognosis of age-related macular degeneration

Unsupervised machine learning has received increased attention in clinical research because it allows researchers to identify novel and objective viewpoints for diseases with complex clinical characteristics. In this study, we applied a deep phenotyping method to classify Japanese patients with age-related macular degeneration (AMD), the leading cause of blindness in developed countries, showing high phenotypic heterogeneity. By applying unsupervised deep phenotype clustering, patients with AMD were classified into two groups. One of the groups had typical AMD features, whereas the other one showed the pachychoroid-related features that were recently identified as a potentially important factor in AMD pathogenesis. Based on these results, a scoring system for classification was established; a higher score was significantly associated with a rapid improvement in visual acuity after specific treatment. This needs to be validated in other datasets in the future. In conclusion, the current study demonstrates the usefulness of unsupervised classification and provides important knowledge for future AMD studies.

Effect of the Duration of Intraretinal or Subretinal Fluid on the Response to Treatment in Undertreated Age-Related Macular Degeneration

We investigated the association between the duration of intraretinal fluid (IRF) or subretinal fluid (SRF) and the response to antivascular endothelial growth factor injection in patients with undertreated age-related macular degeneration (ARMD). The Ethics Committee of Toho University Sakura Medical Center approved this study (no. S18030). Eighty eyes of ARMD patients with VA ≤20/100 were retrospectively assessed. Each injection's efficacy was classified, and the fluid accumulation prior to each injection was evaluated. The effect changes following to accumulated IRF, SRF, the longest persistent IRF period (≥10 months), and their determining factors were evaluated. Throughout observation, acquired refractoriness was rarely associated with increased accumulation of IRF or SRF. The injection span had a tendency to be short, and the polypoidal choroidal vasculopathy and occult choroidal neovasculopathy (CNV) proportions had a tendency to be higher among patients with diminished effects than among those with maintained effects. VA differed significantly with continuous IRF duration, but not with accumulated fluid. The diminishing effect of injections during long-standing IRF was rarely associated with undertreatment. The mechanism underlying acquired refractoriness remains unknown; the effect change demonstrated various patterns, including diminished and improved responses. The longest continuous IRF duration was associated with VA decline. Shortening the duration of continuous IRF may be necessary.

Characteristics of Pachychoroid Diseases and Age-Related Macular Degeneration: Multimodal Imaging and Genetic Backgrounds

The emergence of pachychoroid disease is changing the concept of age-related macular degeneration (AMD). The concept of pachychoroid diseases was developed through clinical observation of multimodal images of eyes with AMD and central serous chorioretinopathy; however, recent genetic studies have provided a proof of concept for pachychoroid spectrum disease, which should be differentiated from drusen-driven AMD. The genetic confirmation of pachychoroid concept further provides novel viewpoints to decode previously reported findings, which facilitates an understanding of the true nature of pachychoroid diseases and AMD. The purpose of this review was to elucidate the relationship between pachychoroid diseases and AMD by interpreting previous findings on pachychoroid diseases and AMD from the novel viewpoints of genetic associations. We confirmed that previous genetic studies supported the concept of pachychoroid diseases. From a genetic viewpoint, the presence of thick choroid and the presence of choroidal vascular hyperpermeability were important characteristics of pachychoroid spectrum diseases. Previous studies have also suggested the classification of polypoidal choroidal vasculopathy (PCV) into two subtypes, pachychoroid neovasculopathy and drusen-driven PCV. Genetic viewpoints will be beneficial to rearrange subtypes of drusen-driven AMD and pachychoroid spectrum diseases. Further genetic studies are needed to investigate pachyvessels, pachydrusen and the significance of polypoidal lesions in pachychoroid neovasculopathy and drusen-driven AMD/PCV.

Latest Developments in Polypoidal Choroidal Vasculopathy: Epidemiology, Etiology, Diagnosis, and Treatment

Polypoidal choroidal vasculopathy (PCV) is a condition characterized by multiple, recurrent, serosanguineous pigment epithelial detachments, and neurosensory retinal detachments due to abnormal aneurysmal neovascular lesions. It is generally considered as a variant of neovascular age-related macular degeneration, but there are some differences between the clinical presentation, natural history, and treatment response between patients with PCV and typical neovascular age-related macular degeneration patients. Over the past decade, new research and technological advancements have greatly improved our understanding of the PCV disease process and the management of PCV. This review aims to summarize the recent research findings to highlight the epidemiology, pathogenesis, genetics, the application of various diagnostic tools for PCV, and the available treatment options for PCV.

Predictive genetics for AMD: Hype and hopes for genetics-based strategies for treatment and prevention

Age-related macular degeneration (AMD) is a complex disease with multiple genetic and environmental risk factors. In the age of molecular genetics, many investigators have established a link between genes and development or progression of the disease. This later evolved to determine whether phenotypic features of AMD have distinct genetic profiles. Molecular genetics have subsequently been introduced as factors in risk assessment models, increasing the predictive value of these tools. Models seek to predict either development or progression of disease, and different AMD-related genes aid our understanding of these respective features. Several investigators have attempted to link molecular genetics with treatment response, but results and their clinical significance vary. Ocular and systemic biomarkers may interact with established genes, promising future routes of ongoing clinical assessment. Our understanding of AMD molecular genetics is not yet sufficient to recommend routine testing, despite its utility in the research setting. Clinicians must be wary of misusing population-based risk models from genetic and biomarker associations, as they are not necessarily relevant for individual counseling. This review addresses the known uses of predictive genetics, and suggests future directions.

Haplotypes of HTRA1 rs1120638, TIMP3 rs9621532, VEGFA rs833068, CFI rs10033900, ERCC6 rs3793784, and KCTD10 rs56209061 Gene Polymorphisms in Age-Related Macular Degeneration

BACKGROUND

To determine the impact of HTRA1 rs1120638, TIMP3 rs9621532, VEGFA rs833068, CFI rs10033900, ERCC6 rs3793784, and KCTD10 rs56209061 genotypes on the development of age-related macular degeneration (AMD) in the Lithuanian population.

METHODS

A total of 916 subjects were examined: 309 patients with early AMD, 301 patients with exudative AMD, and 306 healthy controls. The genotyping of HTRA1 rs11200638, TIMP3 rs9621532, VEGFA rs833068, CFI rs10033900, ERCC6 rs3793784, and KCTD10 rs56209061 was carried out using the RT-PCR method.

RESULTS

Our study showed that single-nucleotide polymorphisms rs3793784 and rs11200638 were associated with increased odds of early and exudative AMD, and the variant in KCTD10 (rs56209061) was found to be associated with decreased odds of early and exudative AMD development after adjustments for age and gender in early AMD analysis and after adjustments only for age in exudative AMD. The haplotype containing two minor alleles C-A and the G-A haplotype in rs3793784-rs11200638 were statistically significantly associated with an increased risk of exudative AMD development after adjustment for age, while the G-G haplotype showed a protective role against early and exudative AMD and the haplotype C-G in rs3793784-rs11200638 was associated with a decreased risk only of exudative AMD development.

CONCLUSIONS

Our study identified two markers, rs11200638 and rs3793784, as risk factors for early and exudative AMD, and one marker, rs56209061, as a protective factor for early and exudative AMD development. The haplotypes constructed of rs3793784-rs11200638 were found to be associated with AMD development, as well.

Pachydrusen in polypoidal choroidal vasculopathy in an Indian cohort

Purpose

To report the prevalence of pachydrusen and their relationship with subfoveal choroidal thickness (SFCT) and large choroidal vessel layer thickness (SF-LCVT) in eyes with polypoidal choroidal vasculopathy (PCV) and their fellow eyes.

Methods

The case records of 50 patients (99 eyes; 59 PCV and 40 fellow eyes) were retrospectively analyzed for the presence of pachydrusen and other drusen types such as soft drusen. The diagnosis was established using colour fundus photography and optical coherence tomography (OCT). SFCT and SF-LCVT were measured and correlated with the different types of drusen.

Results

The mean age of the study cohort was 62.26 ± 10.67 years and included 27 males and 23 females. Pachydrusen and soft drusen were seen in 14 (PCV: 8 and fellow eyes: 6) and 8 eyes (PCV: 2 and fellow eyes: 6) respectively. The mean SFCT and SF-LCVT in the eyes with and without pachydrusen was not significanty different (280.29 ± 103.11 μ vs. 292.63 ± 87.17 μ; P = 0.63 and 180.57 ± 59.20 vs. 173.73 ± 54.86 μ; P = 0.67, respectively). The pachydrusen were most commonly located near the vascular arcades and showed scattered distribution pattern. Though SFCT and SF-LCVT was lower in the eyes with soft drusen compared to eyes with pachydrusen, it failed to reach statistical significance (SFCT, P = 0.1 and SF-LCVT, P = 0.06).

Conclusion

The prevalence of pachydrusen in PCV and their fellow eyes is lower in Indian population suggestive of ethnic variations. SFCT and SF-LCVT was not noted to vary signifcantly in eyes with and without pachydrusen in this study cohort.

PREVALENCE OF POLYPOIDAL CHOROIDAL VASCULOPATHY IN WHITE PATIENTS WITH EXUDATIVE AGE-RELATED MACULAR DEGENERATION: Systematic Review and Meta-Analysis

PURPOSE

Polypoidal choroidal vasculopathy (PCV) is a disease with significant inter-ethnical differences. In this study, we systematically review the literature on the prevalence of PCV in whites referred with a diagnosis of exudative age-related macular degeneration (AMD).

METHODS

We searched PubMed, Embase, the Cochrane Library, and the Web of Science on 24 March, 2017 for studies evaluating the prevalence of PCV in white patients with exudative AMD. Data extraction and risk of bias assessments were performed in duplicate. Studies were included for a qualitative review and a meta-analysis, including subgroup analysis for differences in age and sex.

RESULTS

We included data from 11 studies (>2,200 participants). For diagnosis, indocyanine green angiography was used together with a set of supporting criteria on fundus examination and optical coherence tomography. Extramacular location was more prevalent in eyes with PCV. Drusen was present in the fellow eye in 17% to 27%. Pooled prevalence of PCV in white patients with exudative AMD was 8.7% (confidence interval 95%: 7.2%-10.3%). Patients with PCV were 3.7 years (confidence interval 95%: 2.1 years-5.3 years) younger than those with other exudative AMD. Sex did not differ significantly.

CONCLUSION

Polypoidal choroidal vasculopathy is not a rare subtype of exudative AMD in whites-it is present in approximately one in 11 patients.

Polypoidal choroidal vasculopathy: An update on current management and review of literature

Polypoidal choroidal vasculopathy (PCV) is a subtype of neovascular age-related macular degeneration (nAMD), commonly seen in the Asian population. It is dissimilar in epidemiology, genetic heterogeneity, pathogenesis, natural history, and response to treatment in comparison to nAMD. Confocal scanning laser ophthalmoscopy-based simultaneous fluorescein angiography and indocyanine green angiography, spectral-domain optical coherence tomography (OCT) with enhanced depth imaging, swept-source OCT, and OCT angiography have improved the ability to detect PCV, understand its pathology, and monitor treatment response. A plethora of literature has discussed the efficacy of photodynamic therapy, anti-vascular endothelial growth factor (VEGF) monotherapy, and combination of both, but only a few studies with higher level of evidence and limited follow-up duration are available. This review discusses the understanding of PCV with respect to epidemiology, pathogenesis, clinical features, natural history, imaging techniques, and various treatment options. Recent clinical trials (EVEREST-II and PLANET study) have emphasized that either anti-VEGF monotherapy or combination treatment is equally capable to strike a balance between polyp regression and stabilization of visual acuity. The recurrent nature of the disease, the development of macular atrophy, and the long-term poor visual prognosis despite treatment are concerns that open avenues for further research.

Asian age-related macular degeneration: from basic science research perspective

In Asian populations, polypoidal choroidal vasculopathy (PCV), a distinct phenotype of neovascular age-related macular degeneration (AMD), is more prevalent than Caucasians. Recently, there has been significant focus on how PCV differs from typical AMD. Although typical AMD and PCV share a variety of mechanisms by which abnormal angiogenic process occurs at the retinochoroidal interface, PCV has different clinical characteristics such as aneurysm-like dilation at the terminal of choroidal neovascular membranes, less frequent drusen and inner choroidal degeneration due to the thickened choroid. Recent studies support an important role for inflammation, angiogenesis molecules and lipid metabolism in the pathogenesis of neovascular AMD. Furthermore, although less attention has been paid to the role of the choroid in AMD, accumulating evidence suggests that the choriocapillaris and choroid also play a pivotal role in drusenogenesis, typical AMD and PCV. This review discusses the basic pathogenic mechanisms of AMD and explores the difference between typical AMD and PCV.

Microperimetry and multimodal imaging in polypoidal choroidal vasculopathy

Polypoidal choroidal vasculopathy (PCV) is a degenerative macular disease. The study determined the topographical concordance in the areal extent of PCV, defined by indocyanine green angiography (ICGA), and the corresponding outcomes from spectral-domain optical coherence tomography (SD-OCT) and microperimetry, in 25 individuals (25 eyes) who had undergone 3 months of anti-vascular endothelial growth factor treatment. The differential light sensitivity within 10° eccentricity was evaluated by Pattern Deviation probability analysis. The concordances and proportional areal extents of the abnormality for ICGA, SD-OCT and microperimetry were compared. The concordance in the areal extent between all three modalities was 59%. The median concordance between ICGA and microperimetry was 60%; between ICGA and SD-OCT, 70%; and between SD-OCT and microperimetry, 72%. SD-OCT and microperimetry each identified a greater areal extent (>20%) compared to ICGA in 13 and 19 eyes, respectively. A greater areal extent (>20%) was present in 9 eyes for microperimetry compared to SD-OCT and in 5 eyes for SD-OCT compared to microperimetry. SD-OCT and microperimetry each identified a greater area of abnormality than ICGA which supports the clinical utility of SD-OCT. Strong concordance was present between SD-OCT and microperimetry; however, microperimetry identified additional areas of functional abnormality.

Association of coding and UTR variants in the known regions with wet age-related macular degeneration in Han Chinese population

Age-related macular degeneration (AMD) is the leading cause worldwide of severe visual impairment among people older than 55 years of age. This study aimed to investigate the genetic association between coding and untranslated region (UTR) variants in previously reported loci and exudative age-related macular degeneration (wet AMD) in a Han Chinese population. Using our previously published whole exome sequencing dataset of 349 wet AMD patients and 1253 controls, we searched for associations between coding and UTR variants of the 72 genes located within the 47 reported wet AMD loci regions. From these, 25 variants in 18 of the 72 genes with P < 10 × 10^-3 were selected for the first replication of Sequenom mass-array genotyping in 885 wet AMD subjects and 562 controls. Next, four SNPs were selected for further validation by SNaPshot genotyping in a third Chinese cohort with 456 wet AMD subjects and 211 controls. As a result, we identified two new potential coding and UTR variant SNPs (rs189132250 in BBX located in 3q12.1 and rs144351944 in FILIP1L located in 3q12.1) that showed weak associations with wet AMD in the Han Chinese population. These findings provide new information regarding the coding and UTR variants of the known wet AMD loci in the studied Chinese cohort.

Evaluation of peripheral fundus autofluorescence in eyes with wet age-related macular degeneration

PURPOSE

We aimed to evaluate the prevalence of abnormal peripheral fundus autofluorescence (FAF) in wet age-related macular degeneration (AMD) using wide-field imaging instrument.

PATIENTS AND METHODS

A retrospective, case-controlled study involving 66 eyes of 46 Japanese wet AMD patients and 32 eyes of 20 control patients was performed. Wide-field FAF images were obtained for typical AMD (37 eyes/28 patients), polypoidal choroidal vasculopathy (PCV) (22 eyes/20 patients), and retinal angiomatous proliferation (RAP) (seven eyes/four patients). Two masked ophthalmologists independently graded the images for mottled, granular, and nummular patterns. Main outcome measures were abnormal peripheral FAF frequencies and relative risks by disease subgroups and treatments.

RESULTS

Abnormal peripheral FAF patterns were found in 51.5% of wet AMD eyes compared with 18.8% of control eyes (P<0.001). Mottled, granular, and nummular patterns were found in 45.5%, 31.8%, and 16.7%, respectively, of wet AMD eyes. Each disease subgroup (typical AMD, 54.1%; PCV, 36.4%; and RAP, 85.7%) showed significantly higher frequencies of peripheral FAF (P<0.001, P=0.03, and P<0.001, respectively) than control eyes (18.8%). There were no significant differences (P=0.76) between the frequencies in untreated and treated eyes.

CONCLUSION

Eyes of Japanese wet AMD patients had a higher abnormal FAF prevalence compared with control eyes. Among the three disease subtypes, abnormal patterns were least prevalent in PCV eyes.

Investigation of precursor lesions of polypoidal choroidal vasculopathy using contralateral eye findings

Purpose

The purpose was to investigate precursor lesions of polypoidal choroidal vasculopathy (PCV).

Methods

This cross-sectional study involved 276 unaffected contralateral eyes from unilateral PCV patients (Group 1), unilateral typical exudative age-related macular degeneration (AMD) patients (Group 2), and unilateral epiretinal membrane patients (Group 3) as age-matched controls. Grayish-yellow sub-retinal or sub-retinal-pigment-epithelial deposits larger than 63 μm in size with irregular but discrete margins were defined as drusen-like deposits (DLDs). The frequencies of DLDs, drusen, and pigmentary changes in each group were compared.

Results

DLDs larger than 125 μm in size were found more frequently in Group 1 (19.5 %) than in Groups 2 (3.4 %) and 3 (3.2 %) (p < 0.001). Soft drusen were discovered more frequently in Group 2 eyes than in Groups 1 and 3 (p < 0.001). Pigmentary changes were found more frequently in Groups 1 and 2 compared to Group 3. Compared with the other groups, Group 1 manifested a higher frequency of choroidal vascular hyperpermeability (p < 0.005) and thicker choroid (p < 0.001).

Conclusions

The precursor lesions of PCV are different from those of exudative AMD. DLDs larger than 125 μm and pigmentary changes may be early preclinical markers of PCV. Long-term longitudinal studies are warranted for validation.

Resistance to anti-VEGF therapy in neovascular age-related macular degeneration: a comprehensive review

As a progressive chronic disease, age-related macular degeneration (AMD) is the leading cause of irreversible vision impairment worldwide. Experimental and clinical evidence has demonstrated that vascular endothelial growth factor (VEGF) plays a vital role in the formation of choroidal neovascularization. Intravitreal injections of anti-VEGF agents have been recommended as a first-line treatment for neovascular AMD. However, persistent fluid or recurrent exudation still occurs despite standardized anti-VEGF therapy. Patients suffering from refractory or recurrent neovascular AMD may develop mechanisms of resistance to anti-VEGF therapy, which results in a diminished therapeutic effect. Until now, there has been no consensus on the definitions of refractory neovascular AMD and recurrent neovascular AMD. This article aims at clarifying these concepts to evaluate the efficacy of switching drugs, which contributes to making clinical decision more scientifically. Furthermore, insight into the causes of resistance to anti-VEGF therapy would be helpful for developing possible therapeutic approaches, such as combination therapy and multi-target treatment that can overcome this resistance.

Age-related macular degeneration and polypoidal choroidal vasculopathy in Asians

Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in elderly people globally. It is estimated that there will be more Asians with AMD than the rest of the world combined by 2050. In Asian populations, polypoidal choroidal vasculopathy (PCV) is a common subtype of exudative AMD, while choroidal neovascularization secondary to AMD (CNV-AMD) is the typical subtype in Western populations. The two subtypes share many common clinical features and risk factors, but also have different epidemiological and clinical characteristics, natural history and treatment outcomes that point to distinct pathophysiological processes. Recent research in the fields of genetics, proteomics and imaging has provided further clarification of differences between PCV and CNV-AMD. Importantly, these differences have manifested as disparity in response to intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) treatment between PCV and CNV-AMD, emphasizing the need for accurate diagnosis of PCV and in distinguishing PCV from CNV-AMD, particularly in Asian patients. Current clinical trials of intravitreal anti-VEGF therapy and photodynamic therapy will provide clearer perspectives of evidence-based management of PCV and may lead to paradigm shifts in therapeutic strategies away from those currently employed in the treatment of CNV-AMD. Further research is needed to clarify the relative contribution of specific pathways in inflammation, complement activation, extracellular matrix dysregulation, lipid metabolism and angiogenesis to the pathogenesis of PCV. Findings from this research, together with improved diagnostic technology and new therapeutics, will facilitate more optimal management of Asian AMD.

THREE-YEAR RESULTS OF POLYPOIDAL CHOROIDAL VASCULOPATHY TREATED WITH PHOTODYNAMIC THERAPY: Retrospective Study and Systematic Review

PURPOSE

To evaluate the 3-year outcome in eyes with polypoidal choroidal vasculopathy (PCV) treated with photodynamic therapy with verteporfin.

METHODS

Retrospective study and review of the literature. We performed a retrospective study of patients with PCV who were treated with photodynamic therapy between January 2007 and December 2008. Patients were excluded if they had received photodynamic therapy before the study period, but those who received previous treatment with other modalities (thermal laser or intravitreal therapies) were allowed. The main outcome measures were best-corrected visual acuity, repeat photodynamic therapy, and recurrence of PCV at the end of Years 1, 2, and 3. We further conducted a systematic review of the literature using the terms "polypoidal choroidal vasculopathy" and "photodynamic therapy" and compared the visual outcome of studies over 3 years using meta-analytical methods.

RESULTS

The retrospective study included 68 eyes. The mean best-corrected visual acuity was 0.73 ± 0.56 logMAR (20/107, Snellen equivalent) at baseline, 0.73 ± 0.70 logMAR (20/107, Snellen equivalent) at 1 year, 0.96 ± 0.76 logMAR (20/182, Snellen equivalent) at 2 years, and 1.07 ± 0.81 logMAR (20/235, Snellen equivalent) at 3 years. The cumulative recurrence rates of PCV were 16.1% (1 year), 34.9% (2 years), and 52.7% (3 years) and eyes with recurrence were more likely to suffer ≥3 lines loss compared with eyes without recurrence (63.2 vs. 17.6%, P = 0.006). The systematic review summarized results from 48 published studies and our retrospective study. The pooled analysis from 29 studies (316 eyes reporting the 3-year visual outcome) reported mean best-corrected visual acuity improvement of 0.115 logMAR at 1 year (n = 1,669), 0.066 logMAR at 2 years (n = 701), and 0.027 logMAR at 3 years (n = 316). Reported recurrence rates were 5.9% to 50.0% after 1 year, 9.1% to 83.3% after 2 years, and 40.0% to 78.6% after 3 years or longer of follow-up.

CONCLUSION

The visual outcome in eyes with PCV was stable until 2 years, but the outcome at 3 years worsened, particularly in eyes that experienced recurrence.

CFH polymorphisms in a Northern Spanish population with neovascular and dry forms of age-related macular degeneration

PURPOSE

To elucidate the potential role of single-nucleotide polymorphisms (SNPs) in complement factor H (CFH) gene in Northern Spanish patients with age-related macular degeneration (AMD).

METHODS

A case-control study of 130 unrelated native Northern Spanish diagnosed with AMD (46 dry, 35 neovascular and 49 mixed) and 96 healthy controls matched by age and ethnicity were enrolled. DNA was isolated from peripheral blood and genotyped for AMD-associated SNPs (rs3753394, rs529825, rs800292, rs3766404, rs203674, rs10671170, rs3753396 and rs1065489) using TaqMan probes and restriction fragment length polymorphism (RFLP). The association study was performed using the HaploView 4.0 software.

RESULTS

The allelic frequency analysis revealed that rs529825, rs800292, rs203674 and rs10671170 were significantly associated with an increased risk for AMD. The haplotypes CGG (rs3753394, rs529825 and rs800292) and GCAG (rs203674, rs1061170, rs3753396 and rs1065489) were significantly associated with AMD while the haplotypes CAA (rs3753394, rs529825 and rs800292) and TTAG (rs203674, rs1061170, rs3753396 and rs1065489) were found to be protective. Small differ-ences in allelic frequencies were found between dry and neovascular cases; however, these differences were not significant and did not distinguish one form the other.

CONCLUSIONS

This study found significant association of SNPs rs529825, rs800292, rs203674 and rs1061170 in the CFH gene with susceptibility to AMD. We identified haplotypes that confer protection or increased risk of AMD but not specific genetic variants in CFH capable to distinguish the different clinical forms of AMD in this cohort. Collectively, our results confirmed that CFH represents a strong genetic risk factor for this disease in the Northern Spanish population.

Association of age-related macular degeneration and reticular macular disease with cardiovascular disease

Age-related macular degeneration is the leading cause of adult blindness in the developed world. Thus, major endeavors to understand the risk factors and pathogenesis of this disease have been undertaken. Reticular macular disease is a proposed subtype of age-related macular degeneration correlating histologically with subretinal drusenoid deposits located between the retinal pigment epithelium and the inner segment ellipsoid zone. Reticular lesions are more prevalent in females and in older age groups and are associated with a higher mortality rate. Risk factors for developing age-related macular degeneration include hypertension, smoking, and angina. Several genes related to increased risk for age-related macular degeneration and reticular macular disease are also associated with cardiovascular disease. Better understanding of the clinical and genetic risk factors for age-related macular degeneration and reticular macular disease has led to the hypothesis that these eye diseases are systemic. A systemic origin may help to explain why reticular disease is diagnosed more frequently in females as males suffer cardiovascular mortality at an earlier age, before the age of diagnosis of reticular macular disease and age-related macular degeneration.

The Clinical Effectiveness and Cost-Effectiveness of Screening for Age-Related Macular Degeneration in Japan: A Markov Modeling Study

OBJECTIVE

To investigate the cost-effectiveness of screening and subsequent intervention for age-related macular degeneration (AMD) in Japan.

METHODS

The clinical effectiveness and cost-effectiveness of screening and subsequent intervention for AMD were assessed using a Markov model. The Markov model simulation began at the age of 40 years and concluded at the age of 90 years. The first-eye and second-eye combined model assumed an annual state-transition probability, development of prodromal symptoms, choroidal neovascularization (CNV), and reduction in visual acuity. Anti-vascular-endothelial-growth-factor (anti-VEGF) intravitreal injection therapy and photodynamic therapy (PDT) were performed to treat CNV. Intake of supplements was recommended to patients who had prodromal symptoms and unilateral AMD. Data on prevalence, morbidity, transition probability, utility value of each AMD patient, and treatment costs were obtained from published clinical reports.

RESULTS

In the base-case analysis, screening for AMD every 5 years, beginning at the age of 50 years, showed a decrease of 41% in the total number of blind patients. The screening program reduced the incidence of blindness more than did the additional intake of supplements. However, the incremental cost-effectiveness ratio (ICER) of screening versus no screening was 27,486,352 Japanese yen (JPY), or 259,942 US dollars (USD) per quality-adjusted life year (QALY). In the sensitivity analysis, prodromal symptom-related factors for AMD had great impacts on the cost-effectiveness of screening. The lowest ICER obtained from the best scenario was 4,913,717 JPY (46,470 USD) per QALY, which was approximately equal to the willingness to pay in Japan.

CONCLUSIONS

Ophthalmologic screening for AMD in adults is highly effective in reducing the number of patients with blindness but not cost-effective as demonstrated by a Markov model based on clinical data from Japan.

Analysis of Genetic and Environmental Risk Factors and Their Interactions in Korean Patients with Age-Related Macular Degeneration

Purpose

To investigate the association of genetic and environmental factors, and their interactions in Korean patients with exudative age-related macular degeneration (AMD).

Methods

A total of 314 robustly characterized exudative AMD patients, including 111 PCV (polypoidal choroidal vasculopathy) and 154 typical choroidal neovascularization (CNV), and 395 control subjects without any evidence of AMD were enrolled. Full ophthalmologic examinations including fluorescein angiography (FA), indocyanine green angiography (ICG) and optical coherence tomography (OCT) were done, according to which patients were divided into either PCV or typical CNV. Standardized questionnaires were used to collect information regarding underlying systemic diseases, dietary habits, smoking history and body mass index (BMI). A total of 86 SNPs from 31 candidate genes were analyzed. Genotype association and logistic regression analyses were done and stepwise regression models to best predict disease for each AMD subtype were constructed.

Results

Age, spherical equivalent, myopia, and ever smoking were associated with exudative AMD. Age, hypertension, hyperlipidemia, spherical equivalent, and myopia were risk factors for typical CNV, while increased education and ever smoking were significantly associated with PCV (p<.05 for all). Four SNPs, ARMS2/HTRA1 rs10490924, rs11200638, and rs2736911, and CFH rs800292, showed association with exudative AMD. Two of these SNPs, ARMS2/HTRA1 rs10490924 and rs11200638, showed significant association with typical CNV and PCV specifically. There were no significant interactions between environmental and genetic factors. The most predictive disease model for exudative AMD included age, spherical equivalent, smoking, CFH rs800292, and ARMS2 rs10490924 while that for typical CNV included age, hyperlipidemia, spherical equivalent, and ARMS2 rs10490924. Smoking, spherical equivalent, and ARMS2 rs10490924 were the most predictive variables for PCV. When comparing PCV cases to CNV cases, age, BMI, and education were the most predictive risk factors of PCV.

Conclusions

Only one locus, the ARMS2/HTRA1 was a significant genetic risk factor for Korean exudative AMD, including its subtypes, PCV and typical CNV. Stepwise regression revealed that CFH was important to risk of exudative AMD in general but not to any specific subtype. While increased education was a unique risk factor to PCV when compared to CNV, this association was independent of refractive error in this homogenous population from South Korea. No significant interactions between environmental and genetic risk factors were observed.

Gene-gene interaction of CFH, ARMS2, and ARMS2/HTRA1 on the risk of neovascular age-related macular degeneration and polypoidal choroidal vasculopathy in Chinese population

PURPOSE

To evaluate the association and interaction of five single-nucleotide polymorphisms (SNPs) in three genes (CFH, ARMS2, and ARMS2/HTRA1) with neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV) in Chinese population.

METHODS

A total of 300 nAMD and 300 PCV patients and 301 normal subjects participated in the present study. The allelic variants of rs800292, rs2274700, rs3750847, rs3793917, and rs1065489 were determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Gene-gene interactions were evaluated by the data mining approach multifactor-dimensionality reduction (MDR) method.

RESULTS

The risk alleles of CFH rs800292, rs2274700, ARMS2 rs3057847, and ARMS2/HTRA1 rs3793917 showed significant difference between nAMD or PCV patients and controls (all P<0.01). The homozygosity of risk alleles for rs800292, rs2274700, rs3750847, and rs3793917 were significantly different between nAMD patients and controls (all P<0.01), and predisposed to PCV patients (all P<0.01). After cross-validation consistency (CVC) and permutation tests, the two-locus model rs2274700_rs3750847 has a balanced accuracy of 64.37% in predicting nAMD disease risk. The one-marker model, rs3750847, and two-locus model rs2274700_rs3750847 has a balanced accuracy of 66.07% and 65.89% in predicting PCV disease risk, respectively. Furthermore, CFH rs1065489 did not show significant association with nAMD (P>0.01), but was strongly associated with PCV in Chinese patients (P<0.001).

CONCLUSIONS

In this study, we found that the interaction of ARMS2 and ARMS2/HTRA1 is significantly associated with nAMD, and the interaction of CFH and ARMS2 is pronounced in PCV development in Chinese population.

Polypoidal Choroidal Vasculopathy in Asians

Age related macular degeneration (AMD) in Asians has been suggested to differ from their Western counterparts in terms of epidemiology, pathogenesis, clinical presentation and treatment. In particular, polypoidal choroidal vasculopathy (PCV) appears to be the predominant subtype of exudative AMD in Asian populations, in contrast to choroidal neovascularization secondary to AMD (CNV-AMD) in Western populations. Epidemiological data on PCV has been largely limited to hospital-based studies and there are currently no data on the incidence of PCV. Similarities and differences in risk factor profile between PCV and CNV-AMD point to some shared pathogenic mechanisms but also differential underlying mechanisms leading to the development of each phenotype. Serum biomarkers such as CRP, homocysteine and matrix metalloproteinases suggest underlying inflammation, atherosclerosis and deranged extracellular matrix metabolism as possible pathogenic mechanisms. In addition, recent advances in genome sequencing have revealed differences in genetic determinants of each subtype. While the standard of care for CNV-AMD is anti-vascular endothelial growth factor (VEGF) therapy, photodynamic therapy (PDT) has been the mainstay of treatment for PCV, although long-term visual prognosis remains unsatisfactory. The optimal treatment for PCV requires further clarification, particularly with different types of anti-VEGF agents and possible benefits of reduced fluence PDT.

Association of PEDF polymorphisms with age-related macular degeneration and polypoidal choroidal vasculopathy: a systematic review and meta-analysis

This study assesses the association of the pigment epithelium-derived factor (PEDF) gene with age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV). Publications in MEDLINE and EMBASE up to 21/08/2014 were searched for case-control association studies of PEDF with AMD and/or PCV. Reported studies giving adequate genotype and/or allele information were included. Pooled odds ratios (OR) and 95% confidence intervals (CI) of each polymorphism were estimated. Our literature search yielded 297 records. After excluding duplicates and reports with incomplete information, 8 studies were eligible for meta-analysis, involving 2284 AMD patients versus 3416 controls, and 317 PCV patients versus 371 controls. Four PEDF polymorphisms were meta-analyzed: rs1136287, rs12150053, rs12948385 and rs9913583, but none was significantly associated with AMD or PCV. The most-investigated polymorphism, rs1136287, had a pooled-OR of 1.02 (95% CI: 0.94-1.11, P = 0.64) for AMD. In subgroup analysis by ethnicity, no significant association was identified. Polymorphisms present in single report showed no association. Therefore, existing data in literature does not support the role of PEDF in the genetic susceptibility of AMD and PCV, although replication in specific populations is warranted. Since the pooled-sample size for PCV was small, there is a need of PEDF genotyping in larger samples of PCV.

Joint Effect of CFH and ARMS2/HTRA1 Polymorphisms on Neovascular Age-Related Macular Degeneration in Chinese Population

Purpose. The etiology of neovascular age-related macular degeneration (nAMD) cannot be completely explained by identified environmental risk factors or single-locus gene variants. This study was to explore the potential interactions among gene variants on nAMD in Chinese population. Methods. 43 SNPs located in different genes were genotyped in 932 Chinese individuals (464 nAMD patients and 468 controls). We explored the potential interactions among gene variants using generalized multifactor dimensionality reduction (GMDR) algorithm and the method to measure the departure from the additivity model. Results. The joint effect that involved CFH rs1061170 and HTRA1 rs3793917 was shown statistically significant (P < 0.001) with the highest cross-validation consistency (10/10) and the best testing balanced accuracy (64.50%). In addition, based on the method to measure the departure from the additivity model, the synergy index (S) was 2.63 (1.09–6.38) and the attributable proportion due to interaction (AP) was 55.7% (21.4%–89.9%), which suggested that a common pathway may exist for these genes for nAMD. Those who carried CC for rs3793917 and TC/CC for rs1061170 were at the highest risk of nAMD (OR: 9.76, 95% CI: 4.65–20.51). Conclusions. Evidence that the joint effect that involved CFH and ARMS2/HTRA1 may contribute to the risk of neovascular AMD in Chinese population was obtained.

Investigating the CFH Gene Polymorphisms as a Risk Factor for Age-related Macular Degeneration in an Iranian Population

BACKGROUND

Age-related macular degeneration (AMD) is a complex disorder which results in irreversible vision loss and progressive impairment of central vision. Disease susceptibility is influenced by multiple genetic and environmental factors. Single nucleotide polymorphisms (SNP) in the complement factor H gene are the most important genetic risk factors. We conducted a case-control study to investigate the association four SNPs (dbSNP ID: rs800292, rs1061170, rs2274700 and rs3753395) of CFH gene with AMD in the Iranian population.

MATERIALS AND METHODS

We recruited 100 AMD patients and 100 age- and sex-matched normal controls. Direct sequencing for three SNPs (rs800292, rs2274700 and rs3753395) and restriction fragment length polymorphism utilized for rs1061170. Allele and genotype frequencies of SNPs were calculated and tested for departure from Hardy-Weinberg equilibrium using the Chi-square test. An allelic and genotypic association was compared by logistic regression analysis using the SNPassoc.

RESULTS

According to our results, the frequencies of risk allele for all SNPs (G, G, A, and C alleles of rs800292, rs2274700, rs3753395 and rs1061170, respectively) were significantly higher in AMD patients (p value < 0.001). AMD individuals who had at least one copy of the C allele of rs1061170 had an increased risk of disease compared with cases with the T allele. Other studied polymorphisms showed the same association.

CONCLUSION

Our results suggest the contribution of all four predicted CFH polymorphisms in AMD susceptibility among the Iranian population. This association with CFH may lead to early detection and new strategies for prevention and treatment of AMD.

Identification of genome-wide SNP-SNP and SNP-clinical Boolean interactions in age-related macular degeneration

We propose here a methodology to uncover modularities in the network of SNP-SNP interactions most associated with disease. We start by computing all possible Boolean binary SNP interactions across the whole genome. By constructing a weighted graph of the most relevant interactions and via a combinatorial optimization approach, we find the most highly interconnected SNPs. We show that the method can be easily extended to find SNP/environment interactions. Using a modestly sized GWAS dataset of age-related macular degeneration (AMD), we identify a group of only 19 SNPs, which include those in previously reported regions associated to AMD. We also uncover a larger set of loci pointing to a matrix of key processes and functions that are affected. The proposed integrative methodology extends and overlaps traditional statistical analysis in a natural way. Combinatorial optimization techniques allow us to find the kernel of the most central interactions, complementing current methods of GWAS analysis and also enhancing the search for gene-environment interaction.

Prognostic phenotypic and genotypic factors associated with photodynamic therapy response in patients with age-related macular degeneration

BACKGROUND

This study aimed to demonstrate the phenotypic and genotypic factors associated with photodynamic therapy (PDT) for age-related macular degeneration (AMD).

METHODS

The study included 149 patients with exudative AMD treated by PDT. Eight phenotypic factors and ten genotypic factors for three single nucleotide polymorphisms (SNPs; rs800292, rs1061170, rs1410996) in the complement factor H (CFH) gene, rs 11200638-SNP in the high temperature requirement A-1 (HTRA1) gene, two SNPs (rs699947, rs2010963) in the vascular endothelial growth factor (VEGF) gene, and four SNPs (rs12948385, rs12150053, rs9913583, rs1136287) in the pigment epithelium-derived factor (PEDF) gene were evaluated.

RESULTS

A significant association with best-corrected visual acuity change was demonstrated in the greatest linear dimension, presence or absence of pigment epithelial detachment, and HTRA1-rs11200638 genotype statistically (P=3.67×10(-4), 1.95×10(-2), 1.24×10(-3), respectively). Best-corrected visual acuity in patients with AA genotype of HTRA1-rs11200638 significantly decreased compared with that in patients with GG genotype (P=1.33×10(-3)). Logistic regression analyses demonstrated HTRA1-rs11200638 genotype was most strongly associated with best-corrected visual acuity outcome from baseline at 12 months after photodynamic therapy (P=4.60×10(-3); odds ratio 2.363; 95% confidence interval 1.303-4.285).

CONCLUSION

The HTRA1-rs11200638 variant showed the most significant association. Therefore, this variant may be used as a prognostic factor to estimate the PDT response with significant predictive power.

Pilot study of inactive polypoidal lesions in polypoidal choroidal vasculopathy

PURPOSE

This pilot study was conducted to describe the angiographic characteristics of inactive polypoidal lesions that were observed during indocyanine green angiography (ICGA) in polypoidal choroidal vasculopathy (PCV).

METHODS

This was a retrospective study involving 40 eyes of 39 consecutive Chinese patients with PCV with inactive polypoidal lesions. All patients underwent fundus fluorescein angiography and ICGA examinations. We used ICGA to make a definitive diagnosis of PCV in each patient. The clinical and angiographic characteristics of inactive polypoidal lesions were recorded and analyzed.

RESULTS

In the 40 eyes that were studied, the time between receiving an injection of indocyanine green and the initial appearance of inactive polypoidal lesions ranged from 8.2 minutes to 25.1 minutes, with a mean time of 15.1 ± 5.6 minutes. Inactive polypoidal lesions were divided into 4 groups: 5 eyes (12.5%) in the asymptomatic group; 8 eyes (20.0%) in the atrophic and/or cicatricial group; 24 eyes (60.0%) in the combined group (coexisting with active polypoidal lesions); and 3 eyes (7.5%) in the mixed group (coexisting with choroidal neovascularization). Twelve of the 40 eyes were followed up for 9 to 29 months (mean 12.4 ± 5.3 months). Over this time period, inactive polypoidal lesions completely regressed (not observed in ICGA) in 3 eyes (25.0%), partially regressed in 3 eyes (25.0%), and were stable (the same as the first visit) in 6 eyes (50.0%).

CONCLUSIONS

Inactive polypoidal lesions in patients with PCV most commonly appeared during the middle phase of ICGA and were manifested in 4 groups. These lesions represented the sites of PCV in a regressed or quiescent stage.

Genomic aspects of age-related macular degeneration

Age-related macular degeneration (AMD) is a major late-onset posterior eye disease that causes central vision to deteriorate among elderly populations. The predominant lesion of AMD is the macula, at the interface between the outer retina and the inner choroid. Recent advances in genetics have revealed that inflammatory and angiogenic pathways play critical roles in the pathophysiology of AMD. Genome-wide association studies have identified ARMS2/HTRA1 and CFH as major AMD susceptibility genes. Genetic studies for AMD will contribute to the prevention of central vision loss, the development of new treatment, and the maintenance of quality of vision for productive aging.

Early signs of exudative age-related macular degeneration in Asians

Supplemental digital content is available in the text.

Purpose

To investigate the relationship between the early signs of age-related macular degeneration (AMD) and the risk of developing exudative AMD (typical AMD or polypoidal choroidal vasculopathy [PCV]) in the fellow eye of Japanese patients with unilateral exudative AMD, focusing particularly on eyes with only pigmentary abnormality.

Methods

This study is a retrospective observational consecutive case series. We retrospectively reviewed the medical charts of patients who revisited the AMD clinic from 2010 to 2011 and confirmed 129 cases with unilateral exudative AMD at their first visit (baseline). The non-affected eyes at baseline (the second eye) were categorized by the presence of early signs of AMD. The incidence of exudative AMD (typical AMD or PCV) in the fellow eye was confirmed by fluorescein and indocyanine green angiography.

Results

Of the 129 patients, 14 (10.9%) developed exudative AMD in the fellow eye (median follow-up, 3.2 years; n = 7 typical AMD and n = 7 PCV). Eyes with both pigmentary abnormalities and large drusen were more likely to develop typical AMD (age- and sex-adjusted odds ratio = 9.46, 95% confidence interval = 1.05 to 85.0), whereas pigmentary abnormalities without large drusen were associated with PCV (age- and sex-adjusted odds ratio = 15.9, 95% confidence interval = 1.8 to 140.5).

Conclusions

There was a difference in the association between early signs of AMD and incident development of either typical AMD or PCV. Further research is warranted to determine whether pigmentary abnormalities alone may be an important risk factor for PCV in Asians.