Spotlight on reticular pseudodrusen

Functional and structural characteristics in patients with type 3 macular neovascularisation treated with anti-VEGF. Three-year results in real world settings

BACKGROUND

To evaluate the long-term anatomical and functional outcomes of anti-Vascular Endothelial Growth Factor intravitreal injections (anti-VEGF IVI) in patients with type 3 macular neovascularisation (MNV) in real-world settings.

METHODS

Retrospective review of patients with type 3 MNV who received anti-VEGF IVI between 2013 and 2020. Primary outcomes were best corrected visual acuity (BCVA) and central macular thickness (CMT). Secondary outcome was the development of new-onset of foveal-involving geographic atrophy (GA) and disciform scars.

RESULTS

We identified 59 eyes from 48 British patients that met the inclusion criteria. Treatment with anti- VEGF IVI resulted in a statistically significant reduction in median CMT, which was maintained throughout the study period. At 36 months, 24 eyes showed more than 50 μm reduction in CMT, 7 eyes remained stable and only 2 eyes showed an increase in CMT by more than 50μm compared to the baseline. At year three, deterioration was noticed in most eyes (52.78%) and vision remained stable or improved in 47.22% of the eyes. However, the median BCVA was not statistically significant different compared to baseline. During the study period new onset of macula-involving atrophy or scar was noted in 10.2% and 4.3% of the eyes, respectively.

CONCLUSION

In this real-world study, anatomic and functional improvement were recorded 12-months post anti-VEGF IVI in type 3 MNV. Despite sustained anatomical improvement, vision returned back to baseline levels at 36-months. The development of GA and macular scar was only partially responsible for this outcome suggesting a more severe nature of this form of nAMD.

Integrating Machine Learning and Traditional Survival Analysis to Identify Key Predictors of Foveal Involvement in Geographic Atrophy

Purpose

The purpose of this study was to investigate the incidence of foveal involvement in geographic atrophy (GA) secondary to age-related macular degeneration (AMD), using machine learning to assess the importance of risk factors.

Methods

Retrospective, longitudinal cohort study. Patients diagnosed with foveal-sparing GA, having GA size ≥ 0.049 mm² and follow-up ≥ 6 months, were included. Baseline GA area, distance from the fovea, and perilesional patterns were measured using fundus autofluorescence. Optical coherence tomography assessed foveal involvement, structural biomarkers, and outer retinal layers thickness. Onset of foveal involvement was recorded. Foveal survival rates were estimated using Kaplan-Meier curves. Hazard ratios (HRs) were assessed with mixed model Cox regression. Variable Importance (VIMP) was ranked with Random Survival Forests (RSF), with higher scores indicating greater predictive significance.

Results

One hundred sixty-seven eyes (115 patients, average age = 75.8 ± 9.47 years) with mean follow-up of 50 ± 29 months, were included in this study. Median foveal survival time was 45 months (95% confidence interval [CI] = 38-55). Incidences of foveal involvement were 26% at 24 months and 67% at 60 months. Risk factors were GA proximity to the fovea (HR = 0.97 per 10-µm increase, 95% CI = 0.96-0.98), worse baseline visual acuity (HR = 1.37 per 0.1 LogMAR increase, 95% CI = 1.21-1.53), and thinner outer nuclear layer (HR = 0.59 per 10-µm increase, 95% CI = 0.46-0.74). RSF analysis confirmed these as main predictors (VIMP = 16.7, P = 0.002; VIMP = 6.2, P = 0.003; and VIMP = 3.4, P = 0.01). Lesser baseline GA area (HR = 1.09 per 1-mm2 increase, 95% CI = 1.01-1.16) and presence of a double layer sign (HR = 0.42, 95% CI = 0.20-0.88) were protective but less influential.

Conclusions

This study identifies anatomic and functional factors impacting the risk of foveal involvement in GA. These findings may help identify at-risk patients, enabling tailored preventive strategies.

RETINAL OPTICAL COHERENCE TOMOGRAPHY IMAGING BIOMARKERS: A Review of the Literature

PURPOSE

The aim of this literature review was to summarize novel optical coherence tomography (OCT) imaging biomarkers that have recently been described in the literature and are frequently encountered clinically.

METHODS

The literature was reviewed to identify novel OCT biomarkers reported to date. A descriptive summary of all terms and representative illustrations were provided to highlight the most relevant features.

RESULTS

Thirty-seven OCT terminologies were identified. The vitreomacular interface disorder group included the four stages of epiretinal membrane, macular pseudohole, tractional lamellar hole (LH), degenerative LH, cotton ball sign, and foveal crack sign. The age-related macular degeneration group included outer retinal tubulation, multilayered pigment epithelial detachment, prechoroidal cleft, onion sign, double-layer sign, complete outer retinal atrophy, complete retinal pigment epithelium and outer retinal atrophy, and reticular pseudodrusen. The uveitic disorder group consisted of bacillary layer detachment, syphilis placoid, rain-cloud sign, and pitchfork sign. The disorders relating to the toxicity group included flying saucer sign and mitogen-activated protein kinase (MEK) inhibitor-associated retinopathy. The disorders associated with the systemic condition group included choroidal nodules and needle sign. The pachychoroid spectrum group included pachychoroid and brush border pattern. The vascular disorder group included pearl necklace sign, diffuse retinal thickening, disorganization of retinal inner layers, inner nuclear layer microcysts, hyperreflective retinal spots, paracentral acute middle maculopathy, and acute macular neuroretinopathy. The miscellaneous group included omega sign (ω), macular telangiectasia (type 2), and omega sign (Ω).

CONCLUSIONS

Thirty-seven OCT terminologies were summarized, and detailed illustrations consolidating the features of each biomarker were included. A nuanced understanding of OCT biomarkers and their clinical significance is essential because of their predictive and prognostic value.

Prevalence and determinants of subretinal drusenoid deposits in patients' first-degree relatives

PURPOSE

Subretinal drusenoid deposits (SDDs) are distinct extracellular alteration anterior to the retinal pigment epithelium (RPE). Given their commonly uniform phenotype, a hereditary predisposition seems likely. Hence, we aim to investigate prevalence and determinants in patients' first-degree relatives.

METHODS

We recruited SDD outpatients at their visits to our clinic and invited their relatives. We performed a full ophthalmic examination including spectral domain-optical coherence tomography (SD-OCT) and graded presence, disease stage of SDD as well as percentage of infrared (IR) en face area affected by SDD. Moreover, we performed genetic sequencing and calculated a polygenic risk score (PRS) for AMD. We conducted multivariable regression models to assess potential determinants of SDD and associations of SDD with PRS.

RESULTS

We included 195 participants, 123 patients (mean age 81.4 ± 7.2 years) and 72 relatives (mean age 52.2 ± 14.2 years), of which 7 presented SDD, resulting in a prevalence of 9.7%. We found older age to be associated with SDD presence and area in the total cohort and a borderline association of higher body mass index (BMI) with SDD presence in the relatives. Individuals with SDD tended to have a higher PRS, which, however, was not statistically significant in the multivariable regression.

CONCLUSION

Our study indicates a potential hereditary aspect of SDD and confirms the strong association with age. Based on our results, relatives of SDD patients ought to be closely monitored for retinal alterations, particularly at an older age. Further longitudinal studies with larger sample size and older relatives are needed to confirm or refute our findings.

Association between Subretinal Drusenoid Deposits and Age-Related Macular Degeneration in Multimodal Retinal Imaging

Multimodal retinal imaging enables the detection of subretinal drusenoid deposits (SDD) with significantly greater accuracy compared to fundus photography. The study aimed to analyze a relationship between the presence of SDD, the clinical picture of AMD, and disease progression in a 3 year follow-up. A total of 602 eyes of 339 patients with a diagnosis of AMD, of which 121 (55%) had SDD confirmed in multimodal retinal imaging, were enrolled in the study. SDD was related to a more advanced stage of AMD (p = 0.008), especially with the presence of geographic atrophy (OR = 4.11, 95% CI 2.02-8.38, p < 0.001). Eyes with SDD presented significantly lower choroidal and retinal thickness (ATC: 210.5 μm, CRT: 277 μm, respectively) and volume (AVC: 0.17 mm3, CRV: 8.29 mm3, p < 0.001, respectively) compared to SDD-negative eyes (ATC: 203 μm, CRT: 277 μm; AVC: 7.08 mm3, 8.54 mm3, p < 0.001). Accordingly, the prevalence of pachychoroids and pachyvessels was significantly lower in the SDD present group than in eyes without SDD (p = 0.004; p = 0.04, respectively). Neither demographic factors, lipid profile, genetic predisposition, systemic vascular disease comorbidities, nor parameters of retinal vessels were affected by the presence of SDD. We found no effect of SDD presence on AMD progression (p = 0.12). The presence of SDD appeared to be related to local rather than systemic factors.

Subclinical Angioid Streaks with Pseudodrusen: A New Phenotype of Age-Related Macular Degeneration

INTRODUCTION

To describe subclinical angioid streaks (AS) as a frequent, peculiar age-related macular degeneration (AMD) phenotype, comparing features of eyes with subclinical AS with those of eyes with AMD without AS.

METHODS

This was a retrospective, observational study. Among a patient cohort with AMD, we selected patients without known causes for AS whose eyes showed signs of angioid streaks (AS) on structural optical coherence tomography (OCT) but not on fundus examination. Selected OCT features of AS were Bruch's membrane (BM) breaks and large BM dehiscences.

RESULTS

Among 543 eyes of 274 patients with AMD (mean ± standard deviation: 82 ± 7 years), 73 eyes of 46 patients (81 ± 7 years; p = 0.432) showed AS features on OCT (OCT AS) that were not visible on fundus examination. Estimated prevalence of subclinical age-related AS was 13.4% (95% confidence interval 10.3-16.3%) in this AMD population. Fifty-three eyes (73%) with AS features were affected by peripapillary atrophy, often with a "petaloid-like" pattern, similar to typical features of AS disease. Almost all cases (97%) presented reticular pseudodrusen (RPD), with (41%) or without (59%) drusen showing a significant difference in RPD prevalence in OCT AS eyes in comparison to AMD eyes without subclinical AS using generalized estimating equations (P < 0.001). Among the 73 subclinical AS cases, 71 were affected by late AMD (57 with macular neovascularization, 14 with geographic atrophy), showing a more advanced AMD stage in comparison with AMD eyes without subclinical AS (P < 0.001). The following OCT features were disclosed: BM breaks in 100% of cases and BM dehiscences in 37%.

CONCLUSIONS

Subclinical AS in eyes with AMD is a peculiar phenotype of the disease, with features suggesting a primary involvement of Bruch's membrane and clinical similarities with mild, late-onset pseudoxanthoma elasticum.

Inner Retinal Thickness and Vasculature in Patients with Reticular Pseudodrusen

INTRODUCTION

The aim of this study was to investigate retinal layer thickness and vessel density differences between patients with reticular pseudodrusen (RPD) and intermediate dry age-related macular degeneration (iAMD).

METHODS

Participants included in the study were patients diagnosed by retinal specialists with RPD, iAMD, and both RPD and iAMD at our academic referral center, seen from May 2021 until February 2022. The central 3 mm retinal thickness was measured using spectral-domain optical coherence tomography (Heidelberg Spectralis HRA+OCT System; Heidelberg Engineering, Heidelberg, Germany). Individual retinal thickness measurements were obtained from the innermost layer (nerve fiber layer) until the outermost layer (retinal pigment epithelium [RPE]). Each thickness measurement was subdivided into nine Early Treatment Diabetic Retinopathy Study (ETDRS) sectors. For the vessel density, OCT angiography from the Heidelberg Spectralis System was measured using proprietary third-party software (AngioTool; National Institutes of Health, National Cancer Institute, Bethesda, MD). Clinical and demographic characteristics were compared across the three groups (iAMD, RPD, iAMD and RPD) and analyzed with necessary adjustments. Linear mixed-effects models with necessary corrections were employed to compare continuous eye-level measurements between our three groups as well as in pairwise fashion using the R statistical programming software (R version 4.2.1).

RESULTS

A total of 25 eyes of 17 patients with RPD, 20 eyes of 15 patients with iAMD, and 14 eyes of 9 patients with both iAMD and RPD were analyzed. Retinal thickness analysis identified that the superior inner (p = 0.028) and superior outer (p = 0.027) maculas of eyes with both iAMD and RPD were significantly thinner than those with iAMD alone. In eyes with RPD, the superior inner and superior outer RPE (p = 0.011 and p = 0.05, respectively), outer plexiform layer (p = 0.003 and p = 0.013, respectively), and inner nuclear layer (p = 0.034 and p = 0, respectively) were noted to be thinner compared to eyes with iAMD alone. In addition, the macular deep capillary plexus vessel density was significantly reduced in eyes with RPD compared to eyes with iAMD (p = 0.017).

CONCLUSION

Patients with RPD had inner retinal structural as well as vascular changes compared to iAMD patients. Inner retinal vascular attenuation should be investigated further to see if there is a causal association with retinal thinning.

Nascent Geographic Atrophy as a Predictor of Type 3 Macular Neovascularization Development

PURPOSE

To investigate the association of nascent geographic atrophy (GA) preceding the development of exudative type 3 macular neovascularization (MNV) in patients with age-related macular degeneration (AMD).

DESIGN

Retrospective longitudinal study.

PARTICIPANTS

Patients with AMD diagnosed with treatment-naive exudative type 3 MNV in 1 or both eyes were evaluated. Inclusion criteria included serial tracked structural OCT examinations for ≥ 2 years before the detection of exudative type 3 MNV.

METHODS

Clinical characteristics and retinal imaging, including structural OCT at baseline and at each follow-up examination, were analyzed. Eyes showing the presence of nascent GA during the follow-up were selected for analysis of prevalence, and clinical characteristics at the site of subsequent type 3 MNV development.

MAIN OUTCOME MEASURES

Description of the prevalence and clinical characteristics of nascent GA at the site of subsequent type 3 MNV development.

RESULTS

Overall, 97 eyes affected by type 3 MNV meeting inclusion criteria were analyzed. Of 97 eyes (71 patients), 22 eyes of 21 patients (mean age 82 ± 9 years) showed nascent GA preceding exudative type 3 MNV. The observed prevalence of nascent GA preceding exudative type 3 MNV was 22.7% (95% confidence interval, 14.4%-31.0%). Exudative type 3 MNV developed a mean of 9 ± 6 months after detection of nascent GA. The presence of reticular pseudodrusen in the study eye did not significantly influence the timing of exudative type 3 MNV development after the observation of nascent GA (P > 0.1 in all analyses). Reduced best-corrected visual acuity was recorded at the exudative type 3 stage in comparison with the nascent GA stage (P = 0.003).

CONCLUSIONS

As nascent GA may precede the development of exudative type 3 MNV, the detection of nascent GA in eyes with AMD may warrant closer surveillance to identify early exudative type 3 MNV warranting treatment.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Choroidal vascularity index in leptochoroid: A comparative analysis between reticular pseudodrusen and high myopia

PURPOSE

To investigate the choroidal vascularity index (CVI) in patients affected by leptochoroid.

METHODS

Three distinct age-matched cohorts were collected: patients with reticular pseudodrusen (RPD) secondary to age-related macular degeneration, patients with high-myopia, and healthy controls. CVI was calculated in the subfoveal 6000 μm diameter area.

RESULTS

54 eyes (54 patients) were included (18 eyes in each cohort). No statistical differences were disclosed in terms of age between controls, RPD patients (p = 0.062), and myopic patients (p = 0.070). Total choroidal area showed a different distribution among the 3 cohorts (p < 0.001), due to the reduction of luminal and stromal choroidal area in both RPD and myopic groups in comparison to controls (p < 0.001). Interestingly, CVI showed a different distribution between the 3 cohorts (p < 0.001). In detail, RPD group showed no changes in CVI in comparison to controls (p = 1.000), whereas the myopic group showed a higher CVI in comparison to both RPD group and controls (p < 0.001 in both analyses).

CONCLUSIONS

Different changes of the choroidal vascular and stromal components characterize the leptochoroid secondary to RPD eyes and high-myopic eyes. The relative greater impairment of the vascular area in RPD eyes in comparison to myopic eyes could be at the basis of the lower development of RPD in patients with high myopia.

Comparability of automated drusen volume measurements in age-related macular degeneration: a MACUSTAR study report

Drusen are hallmarks of early and intermediate age-related macular degeneration (AMD) but their quantification remains a challenge. We compared automated drusen volume measurements between different OCT devices. We included 380 eyes from 200 individuals with bilateral intermediate (iAMD, n = 126), early (eAMD, n = 25) or no AMD (n = 49) from the MACUSTAR study. We assessed OCT scans from Cirrus (200 × 200 macular cube, 6 × 6 mm; Zeiss Meditec, CA) and Spectralis (20° × 20°, 25 B-scans; 30° × 25°, 241 B-scans; Heidelberg Engineering, Germany) devices. Sensitivity and specificity for drusen detection and differences between modalities were assessed with intra-class correlation coefficients (ICCs) and mean difference in a 5 mm diameter fovea-centered circle. Specificity was > 90% in the three modalities. In eAMD, we observed highest sensitivity in the denser Spectralis scan (68.1). The two different Spectralis modalities showed a significantly higher agreement in quantifying drusen volume in iAMD (ICC 0.993 [0.991-0.994]) than the dense Spectralis with Cirrus scan (ICC 0.807 [0.757-0.847]). Formulae for drusen volume conversion in iAMD between the two devices are provided. Automated drusen volume measures are not interchangeable between devices and softwares and need to be interpreted with the used imaging devices and software in mind. Accounting for systematic difference between methods increases comparability and conversion formulae are provided. Less dense scans did not affect drusen volume measurements in iAMD but decreased sensitivity for medium drusen in eAMD.Trial registration: ClinicalTrials.gov NCT03349801. Registered on 22 November 2017.

Correlation between Macular Neovascularization (MNV) Type and Druse Type in Neovascular Age-Related Macular Degeneration (AMD) Based on the CONAN Classification

To investigate associations and predictive factors between macular neovascularization (MNV) lesion variants and drusen types in patients with treatment-naïve neovascular age-related macular degeneration (AMD). Methods: Multimodal imaging was retrospectively reviewed for druse type (soft drusen, subretinal drusenoid deposits (SDDs) or mixed) and MNV type (MNV 1, MNV 2, MNV 1/2 or MNV 3). The Consensus on Neovascular AMD Nomenclature (CONAN) classification was used for characterizing MNV at baseline. Results: One eye of each eligible patient was included (n = 191). Patients with predominant SDDs had an increased adjusted odds ratio (aOR) for MNV 2 (23.4453, p = 0.0025) and any type of MNV 3 (8.7374, p < 0.0001). Patients with MNV 1/2 had an aOR for predominant SDDs (0.3284, p = 0.0084). Patients with MNV1 showed an aOR for SDDs (0.0357, p < 0.0001). Eyes with SDDs only without other drusen types showed an aOR for MNV 2 (9.2945, p < 0.0001). Conclusions: SDDs represent a common phenotypic characteristic in AMD eyes with treatment-naïve MNV. The aOR for eyes with predominant SDDs to develop MNV 2 and MNV 3 was much higher, possibly due to their location in the subretinal space. The predominant druse type may help to predict which type of MNV will develop during the course of AMD.

Gender as an effect modifier in the relationship between hypertension and reticular pseudodrusen in patients with early or intermediate age-related macular degeneration

AIM

To determine whether the prevalence of treated hypertension is higher among males or females with early/intermediate (e/i) age-related macular degeneration (AMD) with and without bilateral reticular pseudodrusen (RPD).

METHODS

Retrospective review of the records of patients with e/iAMD who were recruited into the University of Colorado AMD registry between July 2014 and November 2019. Images were classified using the Beckman Initiative criteria and presence/absence of RPD. Patients were categorized into three groups: 1) e/iAMD with RPD; 2) e/iAMD without RPD; 3) control patients who did not have AMD. Multinomial logistic regression analysis was used for adjusted analysis with odds ratios (OR) and confidence intervals (CI).

RESULTS

There were 260 patients with e/iAMD of which 101 had bilateral RPD and 159 had no RPD, and 221 controls. Overall, 62% of patients were female and the three groups did not differ by gender. When stratified by gender, the female e/iAMD/RPD group had a higher prevalence of hypertension, 64.1% vs 45.2% for controls, OR=2.2 (95%CI: 1.2-4.0). The frequency of hypertension in the e/iAMD/no RPD group was 54.1% and did not significantly differ from the control group. Among males, prevalence rates of treated hypertension did not differ. There is a significant interaction of hypertension and gender for the e/iAMD/RPD group such that women with e/iAMD who had RPD were significantly more likely to have hypertension (P=0.042). This relationship was not significant in the e/iAMD/no RPD group (P=0.269).

CONCLUSION

Among females treated hypertension is significantly higher among e/iAMD/RPD patients, whereas for males there is no significant association.

CHOROIDAL VASCULARITY INDEX IS ASSOCIATED WITH GEOGRAPHIC ATROPHY PROGRESSION

PURPOSE

To investigate the correlation between choroidal vascularity index and the enlargement of geographic atrophy (GA) lesion secondary to age-related macular degeneration during the 2-year follow-up.

METHODS

In this longitudinal observational study, 26 eyes (26 patients, mean age 75.7 ± 8.8 years) affected by GA were included. Choroidal vascularity index was calculated in the subfoveal 3000-µm area. The main outcome measure included correlation analysis between baseline choroidal vascularity index and the rate of GA enlargement.

RESULTS

During the 2-year follow-up, the mean GA area increased from 6.99 ± 5.28 mm2 to 10.69 ± 6.61 mm2(P < 0.001), accounting for a growth rate of 0.35 ± 0.20 and 0.31 ± 0.17 mm/year after the square root transformation in the first and second year of follow-up, respectively. Stromal choroidal area significantly decreased during the 2-year follow-up (P = 0.002). Interestingly, there was a significant correlation between the baseline choroidal vascularity index and the rate of GA enlargement (r=-0.432, P = 0.027) and between stromal choroidal area and the rate of GA enlargement (r = 0.422, P = 0.032). No other significant relationship was disclosed among choroidal parameters with the rate of GA enlargement.

CONCLUSION

Choroidal vascularity index impairment is strictly related to the rate of GA enlargement during the 1-year and 2-year follow-up in patients affected by GA. For this reason, choroidal vascularity index could be considered a predictor of GA progression in the clinical setting, and it could be considered as a new potential biomarker in the efficacy evaluation of new GA interventions.

The Role of Vitamin A in Retinal Diseases

Vitamin A is an essential fat-soluble vitamin that occurs in various chemical forms. It is essential for several physiological processes. Either hyper- or hypovitaminosis can be harmful. One of the most important vitamin A functions is its involvement in visual phototransduction, where it serves as the crucial part of photopigment, the first molecule in the process of transforming photons of light into electrical signals. In this process, large quantities of vitamin A in the form of 11-cis-retinal are being isomerized to all-trans-retinal and then quickly recycled back to 11-cis-retinal. Complex machinery of transporters and enzymes is involved in this process (i.e., the visual cycle). Any fault in the machinery may not only reduce the efficiency of visual detection but also cause the accumulation of toxic chemicals in the retina. This review provides a comprehensive overview of diseases that are directly or indirectly connected with vitamin A pathways in the retina. It includes the pathophysiological background and clinical presentation of each disease and summarizes the already existing therapeutic and prospective interventions.

Subretinal drusenoid deposits: An update

A wide spectrum of phenotypic manifestations characterizes age-related macular degeneration (AMD). Drusen is considered the hallmark of AMD and is located underneath the retinal pigment epithelium (RPE). In contrast, subretinal drusenoid deposits (SDDs), also known as reticular pseudodrusens, are located in the subretinal space, on top of the RPE. SDDs are poorly detected by clinical examination and color fundus photography. Multimodal imaging is required for their proper diagnosis. SDDs are topographically and functionally related to rods. SDDs cause a deep impairment in retinal sensitivity and dark adaptation. SDDs are dynamic structures that may grow, fuse with each other, or regress over time. An intermediate step in some eyes is the development of an acquired vitelliform lesion. The presence of SDD confers an eye a high risk for the development of late AMD. SDD leads to macular neovascularization, particularly type 3, geographic atrophy, and outer retinal atrophy.

Population-Based Prevalence and 5-Year Change of Soft Drusen, Pseudodrusen, and Pachydrusen in a Japanese Population

Purpose

To elucidate the prevalence of soft drusen, pseudodrusen, and pachydrusen and their 5-year changes in a Japanese population.

Design

Longitudinal population-based cohort study conducted from 2013 through 2017.

Participants

Residents 40 years of age or older.

Methods

Nonmydriatic color fundus photographs were used to grade drusen subtypes and retinal pigment epithelium (RPE) abnormalities according to the Three Continent Age-Related Macular Degeneration Consortium. The 5-year changes of each drusen were investigated.

Main Outcome Measures

The prevalence of each drusen subtype and the 5-year changes of each drusen.

Results

Among 1731 participants, 1660 participants had gradable photographs that were assessed. The age-adjusted prevalence of soft drusen, pachydrusen, and pseudodrusen was 4.3% (95% confidence interval [CI], 3.2%–5.8%), 7.7% (95% CI, 6.2%–9.7%), and 2.8% (95% CI, 1.7%–4.2%), respectively. Pachydrusen accounted for 82.0% (n = 50) of the extramacular drusen (n = 61). Pigment abnormalities were seen in 28.3% and 8.3% of eyes with soft drusen and pachydrusen, respectively (P < 0.0001). Longitudinal changes were investigated in 1444 participants with follow-up examinations, which showed an increase in size in 8.3% and 3.7% and regression in 1.7% and 5.5% for eyes with soft drusen and pachydrusen, respectively. No participants demonstrated RPE atrophy after pachydrusen regression.

Conclusions

The prevalence of pachydrusen was higher than that of soft drusen and pseudodrusen combined. Pachydrusen may regress over time and typically is not associated with RPE atrophy as detected using color fundus photographs.

International Harmonization of Nomenclature and Diagnostic Criteria (INHAND): Non-proliferative and Proliferative Lesions of the Non-human Primate (M. fascicularis)

The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions Project (www.toxpath.org/inhand.asp) is a joint initiative of the Societies of Toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP) and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature for classifying microscopic lesions observed in most tissues and organs from the nonhuman primate used in nonclinical safety studies. Some of the lesions are illustrated by color photomicrographs. The standardized nomenclature presented in this document is also available electronically on the internet (http://www.goreni.org/). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous lesions as well as lesions induced by exposure to test materials. Relevant infectious and parasitic lesions are included as well. A widely accepted and utilized international harmonization of nomenclature for lesions in laboratory animals will provide a common language among regulatory and scientific research organizations in different countries and increase and enrich international exchanges of information among toxicologists and pathologists.

The Development of Macular Atrophy in Patients with Wet Age-Related Macular Degeneration Receiving Anti-VEGF Treatment

Age-related macular degeneration (AMD) is a leading cause of blindness. Late AMD can be classified into exudative (commonly known as wet AMD [wAMD]) or dry AMD, both of which may progress to macular atrophy (MA). MA causes irreversible vision loss and currently has no approved pharmacological treatment. The standard of care for wAMD is treatment with anti-vascular endothelial growth factors (VEGF). However, recent evidence suggests that anti-VEGF treatment may play a role in the development of MA. Therefore, it is important to identify risk factors for the development of MA in patients with wAMD. For example, excessive blockade of VEGF through intense use of anti-VEGF agents may accelerate the development of MA. Patients with type III macular neovascularisation (retinal angiomatous proliferation) have a particularly high risk of MA. These patients are characterised as having a pre-existing thin choroid (age-related choroidopathy), suggesting that the choroidal circulation is unable to respond to increased VEGF expression. Evidence suggests that subretinal fluid (possibly indicative of residual VEGF activity) may play a protective role. Patients receiving anti-VEGF agents must be assessed for overall risk of MA and there is an unmet medical need to prevent the development of MA without undertreating wAMD.

Choroidal Vascularity Index in Different Cohorts of Dry Age-Related Macular Degeneration

Purpose

The purpose of this study was to investigate the choroidal luminal and interstitial stromal alterations using choroidal vascularity index (CVI) among different cohorts of dry age-related macular degeneration (dAMD) compared to healthy subjects.

Methods

Four distinct cohorts were collected: three different cohorts of patients with dAMD (i.e. drusen, reticular pseudodrusen [RPD], and geographic atrophy [GA]) and an age-matched cohort of healthy subjects (controls). CVI (the ratio between the luminal choroidal area [LCA] and the total choroidal area [TCA]) was calculated in the subfoveal 1000 µm area.

Results

One hundred twenty eyes (from 120 patients) were included (30 eyes in each cohort). The mean age was 76.6 ± 7.1 years. No statistical differences were disclosed in terms of age, axial length, and central macular thickness among study groups. TCA showed a different distribution among the four cohorts (P = 0.003), mainly due to the LCA changes (P = 0.001). Interestingly, CVI showed a different distribution among the four cohorts (P < 0.001). RPD showed a lower CVI in comparison to controls (P = 0.040), whereas GA showed a lower CVI in comparison to drusen, RPD, and controls (P = 0.001, P = 0.046, and P < 0.001, respectively).

Conclusions

Different cohorts of dAMD are characterized by different impairments of the choroidal vascular and stromal components, reflecting different degrees of AMD severity.

Translational Relevance

CVI provides insights for better understanding the pathogenesis of AMD.

Retinal and Choroidal Pathologies in Aged BALB/c Mice Following Systemic Neonatal Murine Cytomegalovirus Infection

Although pathologies associated with acute virus infections have been extensively studied, the effects of long-term latent virus infections are less well understood. Human cytomegalovirus, which infects 50% to 80% of humans, is usually acquired during early life and persists in a latent state for the lifetime. The purpose of this study was to determine whether systemic murine cytomegalovirus (MCMV) infection acquired early in life disseminates to and becomes latent in the eye and if ocular MCMV can trigger in situ inflammation and occurrence of ocular pathology. This study found that neonatal infection of BALB/c mice with MCMV resulted in dissemination of virus to the eye, where it localized principally to choroidal endothelia and pericytes and less frequently to the retinal pigment epithelium (RPE) cells. MCMV underwent ocular latency, which was associated with expression of multiple virus genes and from which MCMV could be reactivated by immunosuppression. Latent ocular infection was associated with significant up-regulation of several inflammatory/angiogenic factors. Retinal and choroidal pathologies developed in a progressive manner, with deposits appearing at both basal and apical aspects of the RPE, RPE/choroidal atrophy, photoreceptor degeneration, and neovascularization. The pathologies induced by long-term ocular MCMV latency share features of previously described human ocular diseases, such as age-related macular degeneration.

Clinical and Multimodal Imaging Features of Subretinal Drusenoid Deposits

Purpose

To describe the multimodal imaging (MMI) features of subretinal drusenoid deposits (SDD) in Indian population.

Methods

Patients diagnosed to have SDD from January 2016 to December 2018 at our tertiary care center were recruited. The diagnosis of SDD was made on the basis of MMI consisting of a combination of color fundus photography (CFP), optical coherence tomography (OCT), red-free (RF) imaging, blue autofluorescence (BAF), and near-infra red reflectance (NIR) imaging. The morphological type and distribution of SDD and the associated retinal lesions were reviewed.

Results

Twenty-three patients with SDD were included. The mean age of the patients was 68.1 ± 12.2 years. SDD were noted in 77.8% of eyes clinically (n = 35/45) and could be detected in 100% of these eyes with OCT. The morphology of SDD was nodular in 65.7% of eyes (n = 23/35), reticular in 5.7% (n = 2/35), and mixed pattern in the remaining cases. BAF and NIR showed hyporeflective nodular lesions often with a target configuration. The location was commonly in the perifoveal area, mostly involving the superotemporal quadrant (74.3%, n = 26/35). Associated retinal lesions were type-3 neovascularization or retinal angiomatous proliferation in 17.1% (n = 6/35), disciform scar in 11.4% (n = 4/35), type-1 neovascularization in 8.5% (n = 3/35), and geographic atrophy in 5.7% (n = 2/35) of eyes. The mean subfoveal choroidal thickness was 186.2 ± 57.8 µm.

Conclusion

SDD commonly have a nodular morphology and their identification often requires confirmations with OCT. Advanced age-related macular degeneration features are frequently present in eyes with SDD and the fellow eyes.

Effects of subthreshold nanosecond laser therapy in age-related macular degeneration using artificial intelligence (STAR-AI Study)

PURPOSE

To investigate changes in retinal thickness, drusen volume, and visual acuity following subthreshold nanosecond laser (SNL) treatment in patients with age-related macular degeneration (ARMD).

DESIGN

Retrospective chart review.

METHODS

Patients with intermediate ARMD treated with a single session of SNL (2RT®, Ellex R&D Pty Ltd, Adelaide, Australia) were included. Swept-source optical coherence tomography (OCT) imaging (Triton; Topcon Medical Systems, Tokyo, Japan) was performed within 6 months before and after SNL treatment. Retinal layers were segmented using the artificial intelligence-enabled Orion® software (Voxeleron LLC, San Francisco, USA). The macular region was analyzed according to the Early Treatment Diabetic Retinopathy Study map. Mean difference and standard deviation in baseline and post-treatment retinal layer thicknesses are reported.

RESULTS

37 eyes from 25 patients were included in this study (mean age 74.7±9.2 years). An average of 51±6 spots were applied around the macula of each study eye, with a mean spot power of 0.33±0.04mJ. Increases in total retinal thickness were observed within the outer temporal and inferior sectors (P<0.05). Within the annulus, there was an increase in thickness of the sub-retinal pigment epithelial (RPE) space [0.88±2.41μm, P = 0.03], defined between the RPE and Bruch's membrane. An increase in thickness of 1.13±2.55μm (P = 0.01) was also noted in the inferior sector of the photoreceptor complex, defined from the inner and outer segment junction to the RPE. Decreases in thickness were observed within the superior sector of the inner nuclear layer (INL) [-1.08±2.55μm, P = 0.01], and within the annulus of the outer nuclear layer (ONL) [-1.44±3.55μm, P = 0.02].

CONCLUSIONS

At 6 months post-SNL treatment, there were sectoral increases in OPL, photoreceptor complex, and sub-RPE space thicknesses and sectoral decreases in INL and ONL thicknesses. This pilot study demonstrates the utility of OCT combined with artificial intelligence-enabled software to track retinal changes that occur following SNL treatment in intermediate ARMD.

Characterisation of macular neovascularisation in geographic atrophy

AIM

To characterise macular neovascularisation (MNV) developing in eyes affected by geographic atrophy (GA).

METHODS

In this multicentric longitudinal study involving three retina referral centres, patients previously affected by GA who developed an active MNV were included. Patients were investigated using structural optical coherence tomography (OCT), fundus autofluorescence, OCT-angiography and dye angiographies. Patients were treated with ProReNata antivascular endothelial growth factor (VEGF) injections and were revaluated after treatment.

RESULTS

Among 512 patients previously diagnosed with GA, 40 eyes of 40 patients (mean age 80.8±7.9 years, mean GA area 8.73±7.39 mm²) presented with treatment-naïve exudative MNV (accounting for an estimated prevalence of 7.81%; 5.49 to 10.13, 95% CIs) and thus were included in the analysis. 67.5% of MNVs were classified as type 2 MNV, 25% as type 1, 2.5% as type 3 and 5% as mixed phenotype. In 92.5% of cases, active MNV in GA showed subretinal hyperreflective material with or without evidence of subretinal/intraretinal hyporeflective exudation. During a mean follow-up of 28±25 months, patients were treated with 6.6±6.3 anti-VEGF injections, with 2.9±1.4 injections in the first year of treatment. No patient developed GA enlargement in the area of MNV.

CONCLUSIONS

MNVs in GA showed different features and therapeutic response in comparison to previously reported features of MNV in age-related macular degeneration (AMD) without GA. For these reasons, the combined phenotype (ie, GA with neovascular AMD) should be considered as a distinct entity in the research and clinical setting.

Subthreshold laser treatment for reticular pseudodrusen secondary to age-related macular degeneration

There is a lack of treatment aimed at the regression of reticular pseudodrusen (RPD) secondary to age-related macular degeneration (AMD). The aim of this prospective, pilot study is to evaluate the safety and short-term efficacy of subthreshold laser treatment (SLT) in patients affected by RPD secondary to dry AMD (dAMD). Twenty eyes of 20 patients (mean age 78.4 ± 6.8 years) with RPD secondary to dAMD were prospectively enrolled. All patients were treated in an extrafoveal area of 1.27 mm² using end-point management yellow subthreshold laser and followed for 3 months. Best-corrected visual acuity was 0.140 ± 0.09 LogMAR at the baseline and no changes were observed during the follow-up (p = 0.232). No significant worsening was disclosed before and after the treatment analyzing the macular sensitivity of the treated area (p = 0.152). No topical and/or systemic side effects were disclosed during the 3-month follow-up. The distribution among the RPD stages changed after the treatment (p < 0.001). In detail, in the treated area, we observed a significant increase in the number of Stage 1 RPD during the follow-up (p = 0.002), associated with a significant decrease of Stage 3 RPD (p = 0.020). Outer nuclear layer (ONL) thickness analysis showed a significant increase after the treatment associated with RPD regression (p = 0.001). End-point management SLT appears a safe treatment for RPD secondary to dAMD, showing short-term safety outcomes. Our results suggest that SLT could be effective in inducing a RPD regression in terms of RPD stage and ONL thickening.

Incidence and Risk Factors of Reticular Pseudodrusen Using Multimodal Imaging

Importance

Although retinal multimodal imaging is needed for diagnosing reticular pseudodrusen (RPD), the incidence of RPD in the general population typically has been assessed only using fundus photographs, which may underestimate their incidence.

Objectives

To describe the incidence of RPD using retinal color photographs, spectral-domain optical coherence tomography scans, fundus autofluorescence, and near-infrared reflectance images among individuals 77 years of age or older and to analyze the associated risk factors of RPD.

Design, Setting, and Participants

The ALIENOR (Antioxydants, Lipides Essentiels, Nutrition et Maladies Oculaires) Study is a cohort of French individuals 77 years of age or older. Data for this study were collected between February 22, 2011, and February 15, 2017, with a mean (SD) follow-up of 3.7 (1.0) years (range, 1.2-5.6 years). At baseline, 501 individuals were eligible to participate. Of 1002 eyes, 197 had prevalent RPD, advanced age-related macular degeneration, or ungradable images. Of the remaining 805 eyes, 333 were missing follow-up data; therefore, the statistical analyses included data from 472 eyes. Data management and statistical analyses were performed between March 15, 2017, and April 5, 2019.

Main Outcomes and Measures

Reticular pseudodrusen were considered as present if detected by at least 2 of the following imaging methods: color fundus photographs, fundus autofluorescence, near-infrared reflectance, and spectral-domain optical coherence tomography images.

Results

Of the 472 eyes analyzed, 263 (55.7%) were from female participants, and the mean (SD) age was 81.9 (3.2) years. Forty-three eyes developed RPD, corresponding to an annual incidence rate of 2.9% (95% CI, 1.9%-4.4%) per participant and an estimated 5-year risk of 13.5%. In multivariable analysis, 4 risk factors of incident RPD were identified: subfoveal choroidal thinning (hazard ratio [HR], 0.99; 95% CI, 0.99-1.00 per 10-μm decrease in thickness; P = .02) and the presence of the minor allelic variants rs10490924 for ARMS2 (HR, 3.57; 95% CI, 1.80-7.10; P < .001), rs1061170 for CFH (HR, 2.12; 95% CI, 1.02-4.41; P = .04), and rs10468017 for LIPC (HR, 2.57; 95% CI, 1.37-4.82; P = .003). Lipophilic statin therapy was associated with a lower incidence of RPD (HR, 0.13; 95% CI, 0.02-0.74; P = .02).

Conclusions and Relevance

With the use of multimodal imaging, the RPD incidence rate was higher than previously reported in other population-based studies using fundus color images. Individuals with subfoveal choroidal thinning or carrying minor allelic variants for ARMS2, CFH, or LIPC had an increased risk for RPD, whereas lipophilic statin therapy was associated with a lower incidence.

A Glossary for ''Pseudo'' Conditions in Ophthalmology

The term "pseudo'' refers to ''lying, false, fake, simulation, imitation or spurious.'' In ophthalmological literature, there are many diseases/conditions/signs/phenomena that are considered as "pseudo." A literature search was conducted on the Medical Subject Headings website, and the keywords that were searched in the title and abstract were as follows: (pseudo-), (fake), (false), (mimicker), (simulator), (masquerade), AND (condition) AND(causes) AND (ophthalmology)OR (eye) OR (ocular) OR (ophthalmic) OR (cornea) OR (retina) OR (strabismus) OR (glaucoma). The search was restricted to English language. The major databases such as PubMed, Medline, Scopus, Google Scholar, OVID, EBSCO, and Cochrane Library were searched or investigated for information. The objective of this review is to summarize common ''pseudo'' conditions in ophthalmology and their respective common causes. We believe that the knowledge of these pseudo-conditions will provide significant benefits in the differential diagnosis of various ophthalmic disorders.

Association of plasma trace element levels with neovascular age-related macular degeneration

Although the triggers causing angiogenesis in the context of neovascular age-related macular degeneration (nAMD) are not fully understood, oxidative stress is likely involved. Oxidative stress in the eye can occur through exposure of macular tissues to sunlight and local or systemic exposure to oxidative stressors associated with environmental or lifestyle factors. Because trace elements have been implicated as regulators of oxidative stress and cellular antioxidant defense mechanisms, we hypothesized that they may play a role as a risk factor, modifying the progression toward nAMD. Herein, we determined whether levels of human plasma trace elements are different in 236 individuals with nAMD compared to 236 age-matched controls without AMD. Plasma levels of 16 trace elements including arsenic, barium, calcium, cadmium, cobalt, chromium, copper, iron, magnesium, manganese, molybdenum, lead, antimony, selenium, vanadium and zinc were measured using inductively coupled plasma mass spectrometry. Associations of trace elements with demographic, environmental and lifestyle factors and AMD-associated genetic variants were assessed. Elevated levels of barium and cadmium and reduced levels of chromium were observed in nAMD patients compared to controls. Mean plasma concentrations of barium were 1.35 μg/L (standard deviation [SD] 0.71) in nAMD and 1.15 μg/L (SD 0.63) in controls (P = 0.001). Mean levels of chromium were 0.37 μg/L (SD 0.22) in nAMD and 0.46 μg/L (SD 0.34) in controls (P = 0.001). Median levels for cadmium, which were not normally distributed, were 0.016 μg/L (interquartile range [IQR] 0.001-0.026) in nAMD and 0.012 μg/L (IQR 0.001-0.022) in controls (P = 0.002). Comparison of the Spearman's correlation coefficients between nAMD patients and controls identified a difference in correlations for 8 trace elements. Cadmium levels were associated with the smoking status (P < 0.001), while barium levels showed a trend of association with the usage of antihypertensive drugs. None of the AMD-associated genetic variants were associated with any trace element levels. In conclusion, in this case-control study we detected elevated plasma levels of barium and cadmium and reduced plasma levels of chromium in nAMD patients. An imbalance in plasma trace elements, which is most likely driven by environmental and lifestyle factors, might have a role in the pathogenesis of AMD. These trace elements may be incorporated as biomarkers into models for prediction of disease risk and progression. Additionally, population-based preventive strategies to decrease Cd exposure, especially by the cessation of smoking, could potentially reduce the burden of nAMD. Future studies are warranted to investigate whether supplementation of Cr would have a beneficial effect on nAMD.

Drusen and pachydrusen: the definition, pathogenesis, and clinical significance

The pachychoroid disease spectrum encompasses seven major retinal conditions including central serous chorioretinopathy (CSC), polypoidal choroidal vasculopathy (PCV), and pachychoroid neovasculopathy or type I macular neovascularisation (MNV) secondary to chronic persistent thickening and dysfunction of the choroidal vasculature. Drusen are focal yellow-white deposits of extracellular debris, which consist of complement proteins, esterified and nonesterified cholesterol, apolipoproteins, carbohydrates, and trace elements, above the retinal pigment epithelium (RPE) or between the RPE and Bruch's membrane. Although drusen are an essential disease precursor of advanced age-related macular degeneration (AMD), a new entity "pachydrusen" has been identified to be associated with some of the enitites that constitute the pachychoroid spectrum. It remains to be determined what the exact differences are between soft drusen, pseudodrusen, and pachydrusen in terms of phenotype, genotype, and pathogenesis. Improving our knowledge in these areas will inevitably improve our understanding of their clinical significance especially as in disease prediction in AMD and the pachychroid spectrum disorders. It remains controversial whether PCV is a subtype of AMD. Understanding the pathogenesis of different types of drusen may also help in addressing if phenotype and/or genotype of type 1 MNV associated with pachychoroid are similar to type 1 MNV related to AMD. Furthermore, because pachydrusen links two pachychoroid diseases, CSC and PCV, it is also of great interest to investigate if CSC is an early stage or a predictor of PCV in future research. In this review, we share our experience in clinical practice and the latest published evidence-based literature to emphasize the differences and similarities in morphology, pathogenesis, and clinical significance of drusen and pachydrusen, a new member of the pachychoroid spectrum disorders.

RETINAL ARTERIAL DILATION IS IMPAIRED IN EYES WITH DRUSEN AND RETICULAR PSEUDODRUSEN

PURPOSE

To analyze static characteristics and dynamic functionality of retinal vessels in eyes with drusen and reticular pseudodrusen (RPD) using dynamic vessel analyzer.

METHODS

Patients with clinical diagnosis of isolated RPD or medium-large drusen and healthy controls were enrolled in the study between July 2016 and May 2018. Participants underwent complete ophthalmologic examination, including enhanced depth imaging structural optical coherence tomography, dynamic retinal vessel analysis, and static retinal vessel analysis.

RESULTS

Twenty-eight eyes of 23 patients with drusen (9 men, mean age 77 ± 6 years), 22 eyes of 16 patients with RPD (7 men, mean age: 76 ± 6 years), and 22 eyes of 22 control subjects (11 men, mean age of 75 ± 6 years) were enrolled. Static retinal vessel analysis did not show any significant difference between the three groups for the central retinal artery equivalent (P = 0.11), the central retinal vein equivalent (P = 0.27), and the arteriovenous ratio (P = 0.30). Dynamic vessel analysis showed significantly reduced arterial dilation in eyes with drusen (P = 0.0001) and RPD (P = 0.015) compared with control subjects. No significant difference was seen between drusen and RPD groups (P = 0.32). Dynamic vessel analysis of retinal veins showed no differences between the three groups (P = 0.10).

CONCLUSION

Dynamic vessel analysis in eyes with drusen and RPD revealed an impaired retinal arterial dilation in response to flicker light stimulation, which further supports the relationship between cardiovascular risk and age-related macular degeneration.

Age-related macular degeneration masqueraders: From the obvious to the obscure

Age-related macular degeneration (AMD) is one of the leading causes of blindness worldwide with increasing prevalence owing to increased life expectancy. Intravitreal injections of antivascular endothelial growth factor agents are commonly used in exudative AMD and oral antioxidant medication for nonexudative AMD; however, many disorders mimic exudative and nonexudative AMD, and misdiagnosis can seriously affect the management of these patients. We summarize the demographics and clinical and imaging characteristics of each of the conditions that masquerade as AMD. As some of the conditions have features of AMD, a short update on the classical features of AMD is also included.

Plasma biomarkers of the amyloid pathway are associated with geographic atrophy secondary to age-related macular degeneration

Geographic atrophy (GA) is an advanced form of dry age-related macular degeneration (AMD), in which local inflammation and hyperactivity of the complement pathway have been implicated in its pathophysiology. This study explores whether any surrogate biomarkers are specifically associated with GA. Plasma from subjects with GA, intermediate dry AMD and non-AMD control were evaluated in 2 cohorts. Cohort 1 was assayed in a 320-analyte Luminex library. Statistical analysis was performed using non-parametric and parametric methods (Kruskal-Wallis, principal component analysis, partial least squares and multivariate analysis of variance (MANOVA) and univariate ANCOVAs). Bioinformatic analysis was conducted and identified connections to the amyloid pathway. Statistically significant biomarkers identified in Cohort 1 were then re-evaluated in Cohort 2 using individual ELISA and multiplexing. Of 320 analytes in Cohort 1, 273 were rendered measurable, of which 56 were identified as changing. Among these markers, 40 were identified in univariate ANCOVAs. Serum amyloid precursor protein (sAPP) was analyzed by a separate ELISA and included in further analyses. The 40 biomarkers, sAPP and amyloid-β (Aβ) (1–42) (included for comparison) were evaluated in Cohort 2. This resulted in 11 statistically significant biomarkers, including sAPP and Aβ(1–40), but not Aβ(1–42). Other biomarkers identified included serum proteases- tissue plasminogen activator, tumor-associated trypsinogen inhibitor, matrix metalloproteinases 7 and 9, and non-proteases- insulin-like growth factor binding protein 6, AXL receptor tyrosine kinase, omentin, pentraxin-3 and osteopontin. Findings suggest that there is a preferential processing of APP to Aβ(1–40) over Aβ(1–42), and a potential role for the carboxylase activity of the γ-secretase protein, which preferentially splices sAPPβ to Aβ(1–40). Other markers are associated with the breakdown and remodeling of the extracellular matrix, and loss of homeostasis, possibly within the photoreceptor-retinal pigment epithelium-choriocapillaris complex. These data suggest novel disease pathways associated with GA pathogenesis and could provide potential novel targets for treatment of GA.

Haller's vessels patterns in non-neovascular age-related macular degeneration

PURPOSE

To investigate the optical coherence tomography (OCT) en face reconstruction of the choroid in different phenotypes of non-neovascular age-related macular degeneration (AMD), to identify the relative distribution of the vascular patterns of the Haller's layer in each AMD category.

METHODS

Retrospective study enrolling consecutive patients with non-neovascular AMD. Patients were divided into the following: (1) those with reticular pseudodrusen (RPD); (2) those with small (< 63 μm) or medium-large drusen (63-124 μm); (3) those with geographic atrophy (GA). Qualitative analysis of the en face images provided by CIRRUS HD-OCT 5000 (Carl Zeiss Meditech, Inc., Dublin, USA) was performed, identifying five arrangements of Haller's vessels: temporal herringbone, branched from below, laterally diagonal, double arcuate, and reticular. Choroidal thickness (CT) was measured from structural OCT. Healthy age-matched subjects were included as a control group.

RESULTS

Fifty-eight eyes of 58 patients (20 eyes with RPD; 22 eyes with drusen; 16 eyes with GA) and 18 control eyes were enrolled. The laterally diagonal configuration was the most prevalent (40.0%) in the RPD group; the reticular pattern was the most frequent in the drusen group (50.0%); the double arcuate (62.5%) was the most recurrent pattern in patients with GA. In the control group, the temporal herringbone (38.9%) arrangement was the most represented. The CT associated with the temporal herringbone and reticular arrangement was significantly higher compared to the branched from below (p < 0.001), the laterally diagonal (p = 0.014), and the double arcuate pattern (p = 0.009).

CONCLUSION

Different phenotypes of non-neovascular AMD present a specific distribution of vascular arrangement on en face OCT. The temporal herringbone and the reticular pattern (the ones more associated in a physiological setting) disclosed a thicker choroid compared to the arrangements more represented in non-neovascular AMD-correlated phenotypes.

Choroidal changes in intermediate age-related macular degeneration patients with drusen or pseudodrusen

Reticular pseudodrusen are associated with a thinner choroid. The aim of our study was to determine the differences in central choroidal thickness and choriocapillaris vascular flow area between eyes with and without reticular pseudodrusen using swept-source optical coherence tomography and swept-source optical coherence tomography angiography. We conducted a retrospective case control study which included 27 eyes from 27 consecutive patients with intermediate age-related macular degeneration and 17 eyes from 17 healthy participants. Complete ophthalmic examinations were carried out including axial length measurements; fundus color retinography; fundus autofluorescence; swept-source optical coherence tomography and swept-source optical coherence tomography angiography; central choroidal thickness and choriocapillaris vascular flow area. Patients were classified as no reticular pseudodrusen, mild reticular pseudodrusen, and severe reticular pseudodrusen. Mean central choroidal thickness in patients exhibiting severe reticular pseudodrusen (110 ± 56 μm) was significantly smaller than in patients with no reticular pseudodrusen (201 ± 76 μm, p < 0.01). Mean choriocapillaris vascular flow area in severe reticular pseudodrusen patients (45.2% ± 3.0%) was also significantly less than in patients with no (47.9% ± 1.6%, p < 0.001) and mild reticular pseudodrusen (47.7% ± 1.0%, p < 0.05). Stepwise multiple regression models confirmed the association of reticular pseudodrusen with central choroidal thickness (p < 0.001) and choriocapillaris vascular flow area (p < 0.01) even after accounting for age, axial length, and refractive error. Soft drusen were not associated with changes in either central choroidal thickness (p = 0.13) nor choriocapillaris vascular flow area (p = 0.29). A significant, positive relationship was found between central choroidal thickness and choriocapillaris vascular flow area (r = 0.44, p = 0.01). Therefore, both central choroidal thickness and choriocapillaris vascular flow area are decreased in eyes with reticular pseudodrusen, as compared to healthy eyes and intermediate age-related macular degeneration eyes not exhibiting reticular pseudodrusen. In addition, central choroidal thickness and choriocapillaris vascular flow area are related, and the reduction of either is directly associated to the severity of reticular pseudodrusen. Further studies are needed to assess the clinical significance of these findings.

Global Analysis of Macular Choriocapillaris Perfusion in Dry Age-Related Macular Degeneration using Swept-Source Optical Coherence Tomography Angiography

Purpose

Swept-source optical coherence tomography angiography (SS-OCTA) was used to investigate if the clinical stage of dry age-related macular degeneration (AMD) was correlated with global and regional macular choriocapillaris (CC) perfusion.

Methods

In this retrospective, cross-sectional study, 6 × 6-mm SS-OCTA images from eyes with early, intermediate, and advanced dry AMD (56 eyes, 41 patients) were analyzed using algorithms described in the literature to assess regional flow deficit percentage (FD%) and average flow deficit size. Regions were defined by concentric areas centered on the fovea: a 1-mm-diameter area, 3-mm-diameter ring, 5-mm-diameter area, 5-mm-diameter ring, and 6 × 6-mm whole image. Data were modeled using the generalized estimating equations approach.

Results

The relationship between age and CC FD% and average flow deficit size was statistically significant (P ≤ 0.05) in all regions of analysis by linear modeling. The relationship between dry AMD stage and FD% was statistically significant by linear modeling in the 5-mm ring, and between dry AMD stage and average flow deficit size in the 3-mm ring, 5-mm area, 5-mm ring, and 6 × 6-mm whole image.

Conclusions

Linear modeling suggests a statistically significant relationship between dry AMD stage and CC perfusion, most prominent in the more peripheral regions of the macula.

Pentosan-associated maculopathy: prevalence, screening guidelines, and spectrum of findings based on prospective multimodal analysis

OBJECTIVE

To describe the prevalence and spectrum of multimodal imaging findings of pentosan polysulfate sodium (PPS)-associated maculopathy and to recommend dosage-related screening guidelines.

DESIGN

Cross-sectional study.

METHODS

Patients previously or currently treated with PPS at University of California, Los Angeles, were randomly ascertained and prospectively screened for PPS-associated maculopathy with multimodal retinal imaging. Daily and cumulative dosages of PPS exposure were calculated for each patient. Images were studied to identify the characteristic findings of toxicity. The prevalence of PPS-associated maculopathy and screening guidelines were determined.

RESULTS

The prevalence of PPS-associated maculopathy in this cohort was 20% (10/50 patients). Both average duration of PPS therapy and average cumulative dosage were significantly lower in the unaffected (6.3 ± 6.6 years, 691.7 ± 706.6 g) versus the affected groups (20.3 ± 6.6 years, 3375.4 ± 1650.0 g, p < 0.001). Near-infrared reflectance (NIR) illustrated characteristic punctate retinal pigment epithelium (RPE) macular lesions early. Fundus autofluorescence (FAF) showed speckled autofluorescence in the posterior pole with peripapillary extension. Co-localization with optical coherence tomography (OCT) displayed focal RPE thickening and, in more severe cases, RPE atrophy in the macula and even the periphery.

CONCLUSIONS

A prevalence of 20% in this study cohort suggests a significant risk of macular toxicity for PPS-treated patients. Characteristic alterations are best detected with FAF and NIR. More significant PPS exposure was associated with more severe atrophy. We recommend an initial baseline eye examination to include OCT and, most importantly, NIR and FAF with annual retinal imaging thereafter especially with cumulative dosages approaching 500 g. Patients exposed to greater than 1500 g of PPS are at significant risk of retinal toxicity.

Complement factors and reticular pseudodrusen in intermediate age-related macular degeneration staged by multimodal imaging

Objective

Systemic activation of the complement system in intermediate age-related macular degeneration (AMD) is understudied. Moreover, links between the presence of reticular pseudodrusen (RPD) and systemic complement dysregulation have not been studied. The aim of this study was to determine if there is a difference in plasma complement factor levels in intermediate AMD compared with controls, and if complement levels are related to the presence of RPD.

Methods and analysis

Levels of complement factors C1q (µg/mL), C4 (µg/mL), C2 (µg/mL), Mannose Binding Lectin (ng/mL), C4b (µg/mL), C3 (µg/mL), factor B (µg/mL), factor D (µg/mL), properdin (µg/mL), C3a (ng/mL), iC3b/C3b (ng/mL), Ba (ng/mL), factor H (µg/mL), factor I (µg/mL), C5 (µg/mL), C5a (pg/mL) and SC5b-9 (ng/mL) were measured in plasma.

Results

109 cases and 65 controls were included in the study. Thirty-nine (36%) cases had RPD. Significantly lower systemic levels of: C1q (OR 0.96, 95% CI 0.94 to 0.98), factor B (OR 0.98, 95% CI 0.96 to 0.99), iC3b/C3b (OR 0.97, 95% CI 0.95 to 0.98), factor H (OR 0.99, 95% CI 0.98 to 0.99), factor I (OR 0.83, 95% CI 0.77 to 0.89) and C5 (OR 0.94, 95% CI 0.90 to 0.98) were found in cases versus controls. Significantly elevated levels of: C2 (OR 1.29, 95% CI 1.07 to 1.59), C3a (OR 1.03, 95% CI 1.01 to 1.05) Ba (OR 1.03, 95% CI 1.01 to 1.05) and C5a (OR 1.04, 95% CI 1.02 to 1.07) were found in cases versus controls. Systemic levels of complement factors measured were not related to the presence of RPD.

Conclusions

Levels of several systemic complement pathway factors were found to be altered in intermediate AMD. Systemic levels of complement factors were not related to RPD.

Impact of Bleaching on Photoreceptors in Different Intermediate AMD Phenotypes

Purpose

To investigate photoreceptors' structural changes after photobleaching exposure in intermediate age-related macular degeneration (iAMD) eyes with and without reticular pseudodrusen (RPD).

Methods

In this prospective, cross-sectional study, were enrolled iAMD patients and healthy controls. Patients and controls underwent repeated imaging with spectral-domain optical coherence tomography (SD-OCT), at baseline and at three intervals after bleaching, during the subsequent recovery in darkness. Structural changes in photoreceptors were investigated in the foveal region and in four perifoveal areas.

Results

Twenty eyes of 20 iAMD patients (12 with RPD and 8 without RPD) and 15 age-matched healthy controls were enrolled. At baseline, the photoreceptor outer segment (OS) volume was significantly reduced in iAMD eyes with RPD compared with controls, in the foveal and perifoveal regions. In healthy subjects, a precocious increase in OS volume was observed after bleaching in the foveal region, and a rapid recovery to baseline values was recorded. In the perifoveal regions, an increase in OS volume was observed 10 minutes after light onset. In contrast, in iAMD subjects with RPD an altered response to photobleaching, in the foveal and superior and inferior perifoveal regions, was recorded.

Conclusions

Our imaging evidences support the hypothesis that dark adaptation is more altered in eyes with RPD. The structural modifications may explain the functional increased damage of the retinal pigment epithelium and photoreceptors reported in eyes with RPD.

Translational Relevance

OCT imaging may be used to assess dark adaptation in AMD eyes.

Prevalence and Phenotypes of Age-Related Macular Degeneration in Eyes With High Myopia

Purpose

To analyze the frequency and phenotypic variation of AMD in subjects with high myopia (HM), and to describe the clinical course and response to treatment of neovascularization (NV).

Methods

Patients with HM were identified at five retina tertiary referral centers. Inclusion criteria were myopic patients aged 55 years or more with axial lengths equal or greater than 25.5 mm.

Results

A total of 874 eyes from 442 HM subjects older than 55 years were identified and 104 eyes of 54 patients (72 ± 11 years) were included in the study and followed up for 23.5 ± 19.5 months. The estimated AMD frequency in HM subjects over 55 years was 11.9% (95% confidence interval; 9.8%-14.0%). A total of 34 of 104 eyes were diagnosed with drusen, 22 with reticular pseudodrusen (RPD), 28 with both drusen and RPD, and 20 with geographic atrophy. Neovascularization was detected in 52 eyes (50%), and type 1 was the most frequent form (39 eyes, 75%). Overall, NV was treated with 4.6 ± 2.6 anti-VEGF injections. Eyes with treatment-naïve NV at baseline (n = 34) required 3.8 ± 1.5 anti-VEGF injections during the first year of treatment. This exceeded the injection number in the purely myopic population (1.8 to 3.6 injections for the first year).

Conclusions

This study provides evidence to suggest that older patients with HM are at a significant risk of the dry and neovascular forms of AMD. NV in eyes with HM and AMD required more injections in the first year compared to NV in HM eyes without AMD.

Pseudoflow with OCT Angiography in Eyes with Hard Exudates and Macular Drusen

PURPOSE

To analyze "pseudoflow," a false positive flow-artifact observed with optical coherence tomography angiography (OCTA) of stationary hyperreflective structures corresponding to hard exudates and macular drusen.

METHODS

Retrospective case series of patients with hard exudates (due to diabetic macular edema [DME] or retinal vein occlusion [RVO]) or macular drusen (due to nonneovascular, or dry, age-related macular degeneration [AMD]) studied with OCTA by using volume-based projection artifact removal (3D PAR).

RESULTS

OCTA of 20 eyes (10 DME/10 RVO) with hard exudates were analyzed. All eyes exhibited pseudoflow corresponding to hard exudates. Seven eyes concurrently demonstrated hard exudates without pseudoflow that were noted in areas lacking vascular flow in the overlying retina. Eight eyes exhibited suspended scattering particles in motion. In 26 of 30 eyes with nonneovascular AMD, pseudoflow associated with macular drusen of any type was noted. Two of 11 eyes with small drusen, 16 of 17 eyes with medium or large drusen, 5 of 5 eyes with drusenoid pigment epithelial detachment, 12 of 16 eyes with ribbon-like subretinal drusenoid deposits, and 13 of 17 eyes with dot-like SDD exhibited pseudoflow.

CONCLUSIONS

Pseudoflow due to projection artifact is common in eyes with hard exudates or macular drusen. 3D PAR reduces but does not eliminate pseudoflow, and pseudoflow may be detected within the foveal avascular zone, indicating that other factors, such as Z-axis micromotion, may also contribute to pseudoflow.

TRANSLATIONAL RELEVANCE

This study provides insight into the etiology of pseudoflow noted on OCTA and will guide more accurate clinical interpretation and investigation of OCTA images.

In Vivo Mapping of the Choriocapillaris in Healthy Eyes: A Widefield Swept-Source OCT Angiography Study

PURPOSE

To report variation of choriocapillaris flow in peripapillary, macular, and near- and mid-periphery regions in healthy participants using widefield swept-source (SS) OCT angiography (OCTA).

DESIGN

Prospective, cross-sectional study.

PARTICIPANTS

Fifty healthy participants.

METHODS

Healthy young participants were imaged with the SS OCTA system (PLEX Elite 9000; Carl Zeiss Meditec, Inc, Dublin, CA). OCT angiography scans were obtained in primary and extreme gazes and a montage was created automatically. The en face choriocapillaris images then were exported to ImageJ software version 1.50 (National Institutes of Health, Bethesda, MD), and a semiautomated algorithm was used for subsequent quantitative analysis.

MAIN OUTCOME MEASURES

Quantitative analysis of the choriocapillaris performed in 3 different regions: (1) peripapillary, (2) macular, and (3) periphery. In addition, choriocapillaris variables were investigated further in distinct fields within these 3 different regions.

RESULTS

Fifty eyes (50 participants) were included in the analysis. Mean age ± standard deviation was 25.2±5.1 years (median, 24.5 years; range, 20.0-40.0 years). The peripapillary region exhibited the greatest total signal void area (P < 0.0001 vs. the macular region; P < 0.0001 vs. the peripheral region). Within the macular region, the foveal area exhibited a greater total signal void area in comparison with both the parafoveal area (P = 0.009) and the perifoveal area (P = 0.015). In the analysis investigating the near- and mid-periphery region, the temporal sector was characterized by a lower total signal void area compared with both the superior and inferior areas (P = 0.016 and P = 0.003, respectively).

CONCLUSIONS

We report quantitative mapping of the choriocapillaris in healthy individuals. Choriocapillaris perfusion seems to have a wide topographic variation.