Characterization of drusen formation in a primary porcine tissue culture model of dry AMD.

Age-related macular degeneration (AMD) affects millions of individuals worldwide and is a leading cause of blindness in the elderly. In dry AMD, lipoproteinaceous deposits called drusen accumulate between the retinal pigment epithelium (RPE) and Bruch's membrane, leading to impairment of oxygen and nutrient trafficking to the neural retina, and degeneration of the overlying photoreceptor cells. Owing to key differences in human and animal ocular anatomy and the slowly progressing nature of the disease, AMD is not easily modeled in vivo. In this study, we further characterize a "drusen-in-a-dish" primary porcine RPE model system by employing vital lipid staining to monitor sub-RPE deposition over time in monolayers of cells cultured on porous transwell membranes. We demonstrate for the first time using a semi-automated image analysis pipeline that the number and size of sub-RPE deposits increases gradually but significantly over time and confirm that sub-RPE deposits grown in culture immunostain positive for multiple known components found in human drusen. As a result, we propose that drusen-in-a-dish cell culture models represent a high-throughput and cost-scalable alternative to animal models in which to study the pathobiology of drusen accumulation and may serve as useful tools for screening novel therapeutics aimed at treating dry AMD.

Human iPSC-based disease modeling studies identify a common mechanistic defect and potential therapies for AMD and related macular dystrophies.

Age-related macular degeneration (AMD) and related macular dystrophies (MDs) primarily affect the retinal pigment epithelium (RPE) in the eye. A hallmark of AMD/MDs that drives later-stage pathologies is drusen. Drusen are sub-RPE lipid-protein-rich extracellular deposits, but how drusen forms and accumulates is not known. We utilized human induced pluripotent stem cell (iPSC)-derived RPE from patients with AMD and three distinct MDs to demonstrate that reduced activity of RPE-secreted matrix metalloproteinase 2 (MMP2) contributes to drusen in multiple maculopathies in a genotype-agnostic manner by instigating sterile inflammation and impaired lipid homeostasis via damage-associated molecular pattern molecule (DAMP)-mediated activation of receptor for advanced glycation end-products (RAGE) and increased secretory phospholipase 2-IIA (sPLA2-IIA) levels. Therapeutically, RPE-specific MMP2 supplementation, RAGE-antagonistic peptide, and a small molecule inhibitor of sPLA2-IIA ameliorated drusen accumulation in AMD/MD iPSC-RPE. Ultimately, this study defines a causal role of the MMP2-DAMP-RAGE-sPLA2-IIA axis in AMD/MDs.

High-fat and high-sucrose diets induce an experimental rabbit model for age-related macular degeneration (AMD).

Age-related macular degeneration (AMD) is a leading cause of blindness. Metabolic disorders and diets are risk factors. We compared lipid profiles and retinal phenotypes with long-term feeding of four diets in male Chinchilla rabbits. Animals were fed with a normal diet (ND), high-fat (HFD), high-sucrose (HSD), or high-fat and high-sucrose diet (HFSD) for six months. The eyes were examined using multimodal imaging modalities and electroretinogram (ERG). Retinal sections were analyzed using H&E staining, toluidine blue staining, immunostaining, and transmission electron microscopy. Lipids and complement C3 in serum or aqueous humour were measured. RNA sequencing was performed to evaluate the retinal transcriptomes. HFD and HSD had minor effects on lipid profiles but synergistically induced severe dyslipidemia. All diets did not cause obesity. HFSD feeding induced retinal lesions like reticular pseudo-drusen (RPD) and pigmentary abnormalities. The RPD-like lesions were mainly lipid droplets around RPE cells. HFSD induced elevated ocular C3 levels and reduced retinal vessel density. In conclusion, HFD and HSD can synergistically induce normal-weight dyslipidemia and RPD-like retinal lesions. HFSD-fed male Chinchilla rabbits are a good model of early AMD.

AKT2-mediated lysosomal dysfunction promotes secretory autophagy in retinal pigment epithelium (RPE) cells.

Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly, with the non-neovascular or atrophic form being the most common. Current treatment options are limited, emphasizing the urgent need for new therapeutic strategies. Our key finding is that increased levels of AKT2 in the RPE cells impair lysosomal function and trigger secretory autophagy; a non-canonical macroautophagy/autophagy pathway where cellular materials are released via the plasma membrane rather than being degraded by lysosomes. We showed that this process involves a protein complex, AKT2-SYTL1-TRIM16-SNAP23, releasing factors contributing to drusen biogenesis, a clinical hallmark of AMD development. Importantly, SIRT5 can inhibit this pathway, potentially offering a protective effect. Understanding mechanisms by which this non-canonical autophagy pathway promotes extracellular waste accumulation could provide new insights into drusen biogenesis. Future therapies for atrophic AMD could focus on regulating secretory autophagy or manipulating proteins involved in this process.

Clinical correlation of optic nerve head analysis performed by SD-OCT in children with pseudopapilledema and papilledema.

PURPOSE: To investigate some diagnostic indicators in optic nerve head (ONH) analysis of children with 'Pseudopapilledema' and 'Papilledema' by Spectral Domain Optical Coherence Tomography (SD-OCT). METHODS: Medical records of 52 children with optic disc swelling, who were followed up by the departments of pediatric neurology and ophthalmology between May 2018 and May 2019 were reviewed retrospectively. Cases were classified as group 1 (Papilledema secondary to Idiopathic Intracranial Hypertension) including 54 eyes of 27 cases, group 2 (Pseudopapilledema secondary to bilateral optic disc drusen) including 50 eyes of 25 cases and control group. Three-dimensional imaging of ONH, peripapillary retinal nerve fiber layer (RNLF) thickness, Bruch's membrane opening height in the nasal respectively temporal quadrant (BMHN, BMH-T) levels were measured by SD-OCT and B-mode ocular ultrasonography data of all cases were evaluated. RESULTS: When RNFL levels were compared between groups, nasal RNFL levels were found to be significantly higher in group 1 cases compared to group 2 (p < 0.001). In 3D imaging of the ONH among group 1 patients, the mean height of the apex in disc swelling was significantly higher than that of group 2 (p = 0,024). The apex in disc swelling was mostly observed to be localized at the middle and had a diffuse swelling pattern in group 1; whereas, in group 2, the it was localized mostly at the nasal quadrant. This variation was statistically significant (p < 0.001). When, Bruch's membrane opening height in the nasal respectively temporal quadrant (BMHN, BMH-T) levels were compared, the measurements obtained were found to be significantly higher in group 1 (p = 0,050 and p = 0,003 respectively). CONCLUSION: Nasal RNFL values of SD-OCT, Bruch's membrane opening height in the nasal respectively temporal quadrant (BMHN, BMH-T) levels, the location of the apex in disc swelling obtained by 3D analysis of the ONH are found to be potential diagnostic parameters when combined with clinical findings. It is important that the nasal quadrant elevation, where the highest peak in 3D imaging was measured, was higher in the papilledema group. The elevation of the optic disc peak in 3D imaging can be used as a parameter to help clinicians distinguish between optic disc drusen (ODD) and papilledema.

Safety, Tolerability, and Short-Term Efficacy of Low-Level Light Therapy for Dry Age-Related Macular Degeneration.

INTRODUCTION: Photobiomodulation (PBM) has become a promising approach for slowing the progression of early and intermediate dry age-related macular degeneration (dAMD) to advanced AMD. This technique uses light to penetrate tissues and activate molecules that influence biochemical reactions and cellular metabolism. This preliminary analysis is aimed at assessing the safety, tolerability, and short-term effectiveness of the EYE-LIGHT®PBM treatment device in patients with dAMD. METHODS: The EYE-LIGHT® device employs two wavelengths, 590 nm (yellow) and 630 nm (red), in both continuous and pulsed modes. Patients over 50 years of age with a diagnosis of dAMD in any AREDS (Age-Related Eye Disease Study) category were randomly assigned to either the treatment group or the sham group. The treatment plan consisted of an initial cycle of two sessions per week for 4 weeks. Safety, tolerability, and compliance outcomes, along with functional and anatomical outcomes, were assessed at the end of the fourth month. RESULTS: This preliminary analysis included data from 76 patients (152 eyes). All patients were fully compliant with treatment sessions, and only one fifth of patients treated with PBM reported mild ocular adverse events, highlighting exceptional results in terms of tolerability and adherence. Changes in best-corrected visual acuity (BCVA) from baseline to month 4 differed significantly between the sham and PBM-treated groups, favoring the latter, with a higher proportion achieving a gain of five or more letters post-treatment (8.9% vs. 20.3%, respectively; p = 0.043). No significant differences in central subfield thickness (CST) were observed between the two groups over the 4-month period. The study also found a statistically significant disparity in mean drusen volume changes from baseline to month 4 between the groups in favor of patients treated with PBM (p = 0.013). CONCLUSION: These preliminary results indicate that PBM treatment using the EYE-LIGHT® system is safe and well tolerated among patients with dAMD. Furthermore, both functional and anatomical data support the treatment's short-term efficacy. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT06046118.

Are Peripapillary Hyperreflective Ovoid Mass-like Structures with an Elevated Optic Disc Still a Diagnosis Dilemma?

PURPOSE: To identify clinical characteristics that would help make or rule out the diagnosis of idiopathic intracranial hypertension (IIH) in patients referred for papilledema (PE) with peripapillary hyperreflective ovoid mass-like structures (PHOMS). DESIGN: A retrospective cohort study. PARTICIPANTS: All patients referred for PE excluding PE with Frisén grade ≥ 3, optic neuritis, ischemic optic neuropathy, and compressive optic neuropathy. Patients were divided into 2 groups: group 1 = isolated PHOMS; group 2 = PHOMS associated with IIH. METHODS: We analyzed the location of PHOMS based on OCT-enhanced depth imaging (EDI) and calculated their volume. MAIN OUTCOME MEASURES: Peripapillary retinal nerve fiber layer (pRNFL), ganglion cell complex, and volume of PHOMS. RESULTS: A total of 154 patients (308 eyes) were included. Patients' mean age was 29 years, with a female predominance (78%). Peripapillary hyperreflective ovoid mass-like structures were associated with these etiologies: IIH (38.3%), isolated (35.7%), posterior uveitis (11%), optic disc drusen (ODD) (10%), and tilted optic disc (5%). Magnetic resonance imaging (MRI) was performed in 83.1% of cases. More than half of the MRI scans were interpreted as consistent with IIH. However, only 39.7% of these patients had confirmed IIH with 44.5% sensitivity and 55.5% specificity. Peripapillary hyperreflective ovoid mass-like structures were overrepresented in the nasal region (95.5%).The location of PHOMS in the superior or inferior quadrant was significantly associated with IIH or ODD, whereas their presence in the temporal or nasal sector was strongly associated with isolated lesions. The mean and median volume of PHOMS were 1.66 µm3 and 1.50 µm3, respectively. There was a significant difference in PHOMS volume, with a higher volume in patients with IIH (P = 0.0037). Follow-up of these patients at 3 and 6 months demonstrated no significant changes in visual function, as per visual field mean deviation, visual acuity measurements, and ganglion cell layer. Mean pRNFL showed a decrease of -4.225 µm at 3 months and -6.489 µm at 6 months when compared with the initial measurement independent of the etiology. CONCLUSIONS: Isolated PHOMS should be considered as a distinct entity. In asymptomatic patients, PHOMS should be carefully studied. Nasal or temporal location, small volume, and stable aspect over the course of weeks or months are suggestive of this entity. This strategy would considerably reduce the impact on patients' anxiety and morbidity. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Clinical Characteristics of Punctate Hyperfluorescence Spots in the Fellow Eye of Patients with Unilateral Macular Neovascularization with No Drusen.

Objectives: To assess the clinical characteristics of patients with macular neovascularization (MNV) with no drusen in the fellow eye, we investigated the incidence of MNV in fellow eyes and the outcomes of intravitreal aflibercept (IVA) monotherapy in MNV eyes of patients with unilateral MNV with a punctate hyperfluorescence spot (PHS) in the fellow eye. Methods: We retrospectively studied 58 treatment-naïve patients with unilateral MNV with no drusen in the fellow eye. Patients were classified into a PHS group (n = 29) or no-PHS group (n = 29) based on the presence of PHS. We evaluated the incidence of MNV in the fellow eye, and the retreatment rate after initiation of three monthly aflibercept injections over one year. Results: Fellow eyes in the PHS group had a thicker choroid (p < 0.05) and higher prevalence of pachychoroid pigment epitheliopathy (PPE) (p < 0.001). MNV eyes in the PHS group had a thicker choroid (p = 0.09). The PHS group had a lower retreatment rate (p < 0.05) and required fewer injections (p < 0.05) than the no-PHS group. MNV developed in one eye in both the PHS and no-PHS groups, and both cases occurred in areas of hypofluorescence on indocyanine green angiography within the PPE area before the onset of MNV. Conclusions: The PHS group frequently exhibited pachychoroid disease characteristics and responded better to IVA monotherapy than the no-PHS group. These groups may represent distinct populations of patients with unilateral MNV with no drusen in the fellow eye.

Autophagy in drusen biogenesis secondary to age-related macular degeneration.

Age-related macular degeneration (AMD) is an emerging cause of blindness in aged people worldwide. One of the key signs of AMD is the degeneration of the retinal pigment epithelium (RPE), which is indispensable for the maintenance of the adjacent photoreceptors. Because of impaired energy metabolism resulting from constant light exposure, hypoxia, and oxidative stress, accumulation of drusen in AMD-affected eyes is observed. Drusen contain damaged cellular proteins, lipoprotein particles, lipids and carbohydrates and they are related to impaired protein clearance, inflammation, and extracellular matrix modification. When autophagy, a major cellular proteostasis pathway, is impaired, the accumulations of intracellular lipofuscin and extracellular drusen are detected. As these aggregates grow over time, they finally cause the disorganisation and destruction of the RPE and photoreceptors leading to visual loss. In this review, the role of autophagy in drusen biogenesis is discussed since impairment in removing cellular waste in RPE cells plays a key role in AMD progression. In the future, means which improve intracellular clearance might be of use in AMD therapy to slow the progression of drusen formation.

Photobiomodulation efficacy in age-related macular degeneration: a systematic review and meta-analysis of randomized clinical trials.

BACKGROUND: Age-related macular degeneration (AMD) is a leading cause of vision loss. Photobiomodulation (PBM) offers a controversial approach for managing dry AMD, aiming to halt or reverse progression through mitochondrial activity modulation. However, the efficacy and clinical relevance of PBM as a potential approach for managing dry AMD remain debated. METHODS: We systematically searched PubMed, Embase, and Cochrane databases for randomized controlled trials (RCTs) comparing PBM versus a sham in patients with dry AMD. We performed trial sequential analysis (TSA) and minimal clinically important difference (MCID) calculations to assess statistical and clinical significance applying a random-effects model with 95% confidence intervals (CI). RESULTS: We included three RCTs comprising 247 eyes. The pooled analysis showed that PBM significant improved BCVA (MD 1.76 letters; 95% CI: 0.04 to 3.48) and drusen volume (MD -0.12 mm³; 95% CI: -0.22 to -0.02) as compared with a sham control. However, the TSA indicated that the current sample sizes were insufficient for reliable conclusions. No significant differences were observed in GA area. The MCID analysis suggested that the statistically significant results did not translate into clinically significant benefits. In the quality assessment, all studies were deemed to have a high risk of bias. CONCLUSION: This meta-analysis points limitations in the current evidence base for PBM in dry AMD treatment, with issues around small sample sizes. Statistically significant improvements do not translate into clinical benefits. The research underscores need for larger RCTs to validate PBM's therapeutic potential for dry AMD.

A Temporal Association between Regression of Pachydrusen and Use of Proprotein Convertase Subtilisin Kexin 9 Inhibitor: A Case Report.

Introduction: We aim to report the clinical course of a patient with pachychoroidopathy who experienced regression of subfoveal drusen during cholesterol treatment using PCSK9 inhibitors. Case Presentation: A 62-year-old woman who was visually asymptomatic complained of recent visual loss in the left eye (OS). She was diagnosed with foveal pachydrusen (OS) that had remained stable for 10 years. Three months after starting cholesterol treatment with a PCSK9 inhibitor, the latest class of lipid-lowering medication, her vision improved in parallel with gradual regression of material deposited beneath the retinal pigment epithelium (RPE). Recurrence of drusen was observed after discontinuing the drug. Conclusions: Use of PCSK9 inhibitors may improve the retina's lipid homeostasis by increasing the number of RPE-LDL receptors and partly contribute to the improvement of ocular phenotypes associated with dysfunctional RPE in pachychoroidopathy.

Developing an image-based grading scale for peripheral drusen to investigate associations of peripheral drusen type with age-related macular degeneration.

Age-related macular degeneration (AMD) is a leading cause of blindness. It is associated with peripheral drusen which has not been categorized. We investigated peripheral drusen to validate an image grading system and to understand possible associations between peripheral drusen and AMD. We collated clinical data, ultra-widefield (UWF) pseudocolor fundus images and Spectral-Domain Optical Coherence Tomography (SD-OCT) scans from consecutive retinal patients. SD-OCT scans were used to determine AMD stage. A masked retinal specialist recorded the types of peripheral drusen observed in UWF images. Eyes whose UWF images did not pass quality screening and those without AMD and peripheral drusen were excluded from the study. Statistical tests were utilized to determine the validity of our grading system and associations of peripheral drusen with AMD. A total of 481 eyes (283 subjects) were included in the study (mean age 73.1 ± 1.2years, 64.3% female). Interobserver and test-retest statistical analyses to evaluate the UWF image grading system resulted in Cohen's Kappa 0.649 (p < 0.001) and 0.922 (p < 0.001) respectively. A total of 284 (59.0%), 28 (5.8%), 15 (3.1%), 22 (4.6%), 4 (0.8%), 39 (8.1%), and 32 (6.7%) eyes had hard, soft, reticular, cuticular, atrophic, mixed drusen, and mixed drusen and atrophy respectively in at least one peripheral retinal quadrant. Hard peripheral drusen was significantly associated with the presence of AMD (p = 0.010). Peripheral drusen types were variably seen in retinal patients with and without AMD. We validated a peripheral drusen grading system and provided an image library to assist in the identification of peripheral drusen. Our study found an association between peripheral hard drusen and an AMD diagnosis but did not find a link between peripheral drusen and severity of AMD.

Chiari Malformation Type I With Concurrent Bilateral Optic Disc Drusen: Is Follow-up Necessary?

Pseudopapilledema caused by optic disc drusen (ODD) mimics the appearance of papilledema and usually presents as a diagnostic challenge. A young boy with known Chiari malformation type 1 (CM-1) was referred to the pediatric ophthalmology clinic for eye assessment to exclude papilledema due to elevated intracranial pressure (ICP). Despite the ophthalmic examination revealing bilateral optic disc elevation, multimodal imaging techniques such as fundus autofluorescence, optical coherence tomography (OCT), and B-scan ultrasonography are recommended to confirm the distinction between bilateral ODD causing pseudopapilledema and papilledema secondary to elevated ICP. Accidental coexistent papilledema mimickers like ODD need to be considered in patients with CM-1 before making a diagnosis of papilledema to avoid unnecessary invasive procedures. There was no evidence that the presence of ODD excludes the possibility of future optic nerve head changes due to elevated ICP. The multidisciplinary consensus decided on annual ophthalmology follow-ups using multimodal imaging to detect any subtle optic nerve head changes.

Reticular Pseudodrusen: Impact of Their Presence and Extent on Local Rod Function in Age-Related Macular Degeneration.

Purpose: To understand the spatial relationship between local rod-mediated visual function and reticular pseudodrusen (RPD) in eyes with large drusen. Design: Retrospective cross-sectional study. Participants: One eye with large drusen (>125 µm) each from 91 individuals with intermediate age-related macular degeneration, with and without RPD. Methods: All participants underwent dark adaptation testing using a dark-adapted chromatic perimeter, where visual sensitivities were measured over 30 minutes of dark adaptation after photobleach. The rod intercept time (RIT; a measure of dynamic rod function) and pointwise sensitivity difference (PWSD; a relative measure of rod- compared with cone-mediated function) was determined at multiple retinal locations, and their association with the overall (central 20° × 20° region) and local (2° diameter region centered on the location tested) extent of RPD and drusen (quantified using multimodal imaging) was examined. Main Outcome Measures: Association between overall and local extent of RPD and drusen with RIT and PWSD at each retinal location tested. Results: In a multivariable analysis, delayed RIT was associated with an increasing overall (P < 0.001), but not local (P = 0.884), extent of RPD. In contrast, the increasing local (P < 0.001), but not overall (P = 0.475), extent of drusen was associated with delayed RIT. Furthermore, only an increasing overall extent of RPD (P < 0.001) was associated with reduced PWSD (or worse rod compared with cone function), but not the local extent of RPD and drusen, or overall extent of drusen (P ≥ 0.344). Conclusions: Local rod-mediated function was associated with the overall, rather than local, extent of RPD in eyes with large drusen, suggesting that there may be widespread pathologic changes in eyes with RPD that account for this. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Aberrant lipid accumulation and retinal pigment epithelium dysfunction in PRCD-deficient mice.

Progressive Rod-Cone Degeneration (PRCD) is an integral membrane protein found in photoreceptor outer segment (OS) disc membranes and its function remains unknown. Mutations in Prcd are implicated in Retinitis pigmentosa (RP) in humans and multiple dog breeds. PRCD-deficient models exhibit decreased levels of cholesterol in the plasma. However, potential changes in the retinal cholesterol remain unexplored. In addition, impaired phagocytosis observed in these animal models points to potential deficits in the retinal pigment epithelium (RPE). Here, using a Prcd-/- murine model we investigated the alterations in the retinal cholesterol levels and impairments in the structural and functional integrity of the RPE. Lipidomic and immunohistochemical analyses show a 5-fold increase in the levels of cholesteryl esters (C.Es) and lipid deposits in the PRCD-deficient retina, respectively, indicating alterations in total retinal cholesterol. Furthermore, the RPE of Prcd-/- mice exhibit a 1.7-fold increase in the expression of lipid transporter gene ATP-binding cassette transporter A1 (Abca1). Longitudinal fundus and spectral domain optical coherence tomography (SD-OCT) examinations showed focal lesions and RPE hyperreflectivity. Strikingly, the RPE of Prcd-/- mice exhibited age-related pathological features such as lipofuscin accumulation, Bruch's membrane (BrM) deposits and drusenoid focal deposits, mirroring an Age-related Macular Degeneration (AMD)-like phenotype. We propose that the extensive lipofuscin accumulation likely impairs lysosomal function, leading to the defective phagocytosis observed in Prcd-/- mice. Our findings support the dysregulation of retinal cholesterol homeostasis in the absence of PRCD. Further, we demonstrate that progressive photoreceptor degeneration in Prcd-/- mice is accompanied by progressive structural and functional deficits in the RPE, which likely exacerbates vision loss over time.

Retro Mode Imaging for Detection and Quantification of Sub-RPE Drusen and Subretinal Drusenoid Deposits in Age-Related Macular Degeneration.

Background: Drusen and drusenoid deposits are a hallmark of age-related macular degeneration (AMD). Nowadays, a multimodal retinal imaging approach enables the detection of these deposits. However, quantitative data on subretinal drusenoid deposits (SDDs) are still missing. Here, we compare the capability of en-face drusen and SDD area detection in eyes with non-exudative AMD using conventional imaging modalities versus Retro mode imaging. We also quantitatively assess the topographic distribution of drusen and SDDs. Methods: In total, 120 eyes of 90 subjects (mean age ± standard deviation = 74.6 ± 8.6 years) were included. Coherent en-face drusen and SDD areas were measured via near-infrared reflectance, green (G-) and blue (B-) fundus autofluorescence (AF), and Retro mode imaging. Drusen phenotypes were classified by correlating en-face drusen areas using structural high-resolution spectral domain optical coherence tomography. The topographic distribution of drusen was analyzed according to a modified ETDRS (Early Treatment of Diabetic Retinopathy Study) grid. Intraclass correlation coefficient (ICC) analysis was applied to determine the inter-reader agreement in the SDD en-face area assessment. Results: The largest coherent en-face drusen area was found using Retro mode imaging with a mean area of 105.2 ± 45.9 mm2 (deviated left mode (DL)) and 105.4 ± 45.5 mm2 (deviated right mode (DR)). The smallest en-face drusen areas were determined by GAF (50.9 ± 42.6 mm2) and BAF imaging (49.1 ± 42.9 mm2) (p < 0.001). The inter-reader agreement for SDD en-face areas ranged from 0.93 (DR) to 0.70 (BAF). The topographic analysis revealed the highest number of SDDs in the superior peripheral retina, whereas sub-retinal pigment epithelium drusen were mostly found in the perifoveal retina. Retro mode imaging further enabled the detection of the earliest SDD stages. Conclusions: Retro mode imaging allows for a detailed detection of drusen phenotypes. While hundreds/thousands of SDDs can be present in one eye, the impact of SDD number or volume on AMD progression still needs to be evaluated. However, this new imaging modality can add important knowledge on drusen development and the pathophysiology of AMD.

Genetic Insights into Age-Related Macular Degeneration.

One of the major causes of vision impairment among elderly people in developed nations is age-related macular degeneration (AMD). The distinctive features of AMD are the accumulation of extracellular deposits called drusen and the gradual deterioration of photoreceptors and nearby tissues in the macula. AMD is a complex and multifaceted disease influenced by several factors such as aging, environmental risk factors, and a person's genetic susceptibility to the condition. The interaction among these factors leads to the initiation and advancement of AMD, where genetic predisposition plays a crucial role. With the advent of high-throughput genotyping technologies, many novel genetic loci associated with AMD have been identified, enhancing our knowledge of its genetic architecture. The common genetic variants linked to AMD are found on chromosome 1q32 (in the complement factor H gene) and 10q26 (age-related maculopathy susceptibility 2 and high-temperature requirement A serine peptidase 1 genes) loci, along with several other risk variants. This review summarizes the common genetic variants of complement pathways, lipid metabolism, and extracellular matrix proteins associated with AMD risk, highlighting the intricate pathways contributing to AMD pathogenesis. Knowledge of the genetic underpinnings of AMD will allow for the future development of personalized diagnostics and targeted therapeutic interventions, paving the way for more effective management of AMD and improved outcomes for affected individuals.

[Use of artificial intelligence for recognition of biomarkers in intermediate age-related macular degeneration]. / Einsatz von künstlicher Intelligenz zur Erkennung von Biomarkern bei der intermediären altersabhängigen Makuladegeneration.

Advances in imaging and artificial intelligence (AI) have revolutionized the detection, quantification and monitoring for the clinical assessment of intermediate age-related macular degeneration (iAMD). The iAMD incorporates a broad spectrum of manifestations, which range from individual small drusen, hyperpigmentation, hypopigmentation up to early stages of geographical atrophy. Current high-resolution imaging technologies enable an accurate detection and description of anatomical features, such as drusen volumes, hyperreflexive foci and photoreceptor degeneration, which are risk factors that are decisive for prediction of the course of the disease; however, the manual annotation of these features in complex optical coherence tomography (OCT) scans is impractical for the routine clinical practice and research. In this context AI provides a solution by fully automatic segmentation and therefore delivers exact, reproducible and quantitative analyses of AMD-related biomarkers. Furthermore, the application of AI in iAMD facilitates the risk assessment and the development of structural endpoints for new forms of treatment. For example, the quantitative analysis of drusen volume and hyperreflective foci with AI algorithms has shown a correlation with the progression of the disease. These technological advances therefore improve not only the diagnostic precision but also support future targeted treatment strategies and contribute to the prioritized target of personalized medicine in the diagnostics and treatment of AMD.

Diagnostic dilemma of papilledema and pseudopapilledema.

BACKGROUND: Papilledema is the optic disc swelling caused by increased intracranial pressure (ICP) that can damage the optic nerve and cause subsequent vision loss. Pseudopapilledema refers to optic disc elevation without peripapillary fluid that can arise from several optic disc disorders, with optic disc drusen (ODD) being the most frequent cause. Occasionally, pseudopapilledema patients are mistakenly diagnosed as papilledema, leading to the possibility of unneeded procedures. We aim to thoroughly examine the most current evidence on papilledema and pseudopapilledema causes and several methods for distinguishing between both conditions. METHODS: An extensive literature search was conducted on electronic databases including PubMed and google scholar using keywords that were relevant to the assessed pathologies. Data were collected and then summarized in comprehensive form. RESULTS: Various techniques are employed to distinguish between papilledema and pseudopapilledema. These techniques include Fundus fluorescein angiography, optical coherence tomography, ultrasonography, and magnetic resonance imaging. Lumbar puncture and other invasive procedures may be needed if results are suspicious. CONCLUSION: Papilledema is a sight-threatening condition that may lead to visual affection. Many disc conditions may mimic papilledema. Accordingly, differentiation between papilledema and pseudopailledema is crucial and can be conducted through many modalities.