METHYLATION-ASSOCIATED PATHWAYS IN MACULAR TELANGIECTASIA TYPE 2 AND OPHTHALMOLOGIC FINDINGS IN PATIENTS WITH GENETIC METHYLATION DISORDERS.

PURPOSE: Serine (Ser) and glycine (Gly) levels were reported to differ between patients with macular telangiectasia type 2 (MacTel) compared with healthy controls. Because they are closely related to methylation metabolism, this report investigates methylation-associated metabolite levels in patients with MacTel and retinal changes in monogenetic methylation disorders. METHODS: Prospective, monocentric study on patients with MacTel and healthy controls underwent a standardized protocol including a blood draw. Methylation-associated metabolite levels in plasma were determined using targeted quantitative metabolomics. Furthermore, patient records of cystathionine beta-synthase, methylenetetrahydrofolate reductase, and methylmalonic aciduria and homocystinuria type C protein (MMACHC) deficiency were screened for reported retinal changes. RESULTS: In total, 29 patients with MacTel and 27 healthy controls were included. Patients with MacTel showed lower plasma Ser ( P = 0.02 and P = 0.01) and Gly ( P = 0.11 and P = 0.11) levels than controls. Principal component analyses revealed that methylation-associated metabolite, especially homocysteine, contributed to a distinct clustering of patients with MacTel. No retinal changes were seen in cystathionine beta-synthase (n = 1) and methylenetetrahydrofolate reductase (n = 2) deficiency, while two patients with MMACHC (n = 4) deficiency displayed extensive macular dystrophy. CONCLUSION: Patients with MacTel show distinct clustering of methylation-associated metabolite compared with controls. Of the three homocystinurias, only MMACHC resulted in macular dystrophy, possibly due to distinct compensatory pathways.

Psychometric assessment of patients with central serous chorioretinopathy and correlation with disease stage and progression: a case control study.

BACKGROUND: Central serous chorioretinopathy (CSC) has frequently been associated with increased stress levels as well as an increased prevalence of other psychiatric conditions. This study used standardized psychometric scores to assess stress, depression and anxiety levels of CSC patients and compared them to controls without retinal disease ("healthy") and with branch retinal vein occlusion (BRVO). METHODS: Monocentric, longitudinal case control study on consecutive CSC patients seen at a tertiary referral center. Controls without retinal disease were recruited from the oculoplastics clinic and those with BRVO from the medical retina clinic. Patients completed pseudonymized tests measuring stress levels (PHQ-stress), depression (PHQ-9) and anxiety (GAD-7) at baseline and at 3- and 6-months follow-up. Higher scores indicated higher trait levels. RESULTS: 65 CSC patients, 19 healthy controls and 19 BRVO patients were included in this study. CSC patients showed significantly higher stress levels at baseline compared to controls (p = 0.009), but not compared to BRVO patients (p = 1.00). At 3- and 6-months follow-up, no significant difference between groups was observed anymore. Acute CSC patients showed higher scores than those with chronic CSC, which also subsided over time. Depression and anxiety scores did not differ between groups at any timepoint. CONCLUSIONS: Patients with CSC do not show higher initial stress levels than patients with BRVO, while anxiety and depression levels did not differ from controls. Stress may thus rather represent a consequence of the onset of visual deterioration observed in CSC or other ocular diseases.

Clinical Landscape of Central Serous Chorioretinopathy in Germany: Retina.net CSC Registry Report Number 1.

INTRODUCTION: The German Registry of central serous chorioretinopathy (CSC) collects data on CSC patients in a nationwide multicenter approach to analyze epidemiology, risk factors, clinical presentations, as well as diagnosis and treatment patterns. METHODS: In this multicenter cohort study, patients with CSC were enrolled in nine tertiary referral centers in Germany between January 2022 and June 2023. After consenting to the study, demographic data, risk factors, reported symptoms, best-corrected visual acuity (BCVA), funduscopic findings, disease severity, and diagnostic and treatment decisions were recorded and analyzed. RESULTS: A total of 539 eyes of 411 CSC patients were enrolled in this study including 308 males (75%) and 103 females (25%). Patients were predominantly of Caucasian origin and had a mean age of 55.5 years (IQR 41.0-70.0). 28% of eyes were classified as acute (<4 months duration) CSC, 28% as chronic (>4 months duration) CSC, 21% as inactive CSC, 11% as chronic atrophic CSC, and 12% as CSC with secondary CNV. 128 patients (31%) demonstrated bilateral CSC. The most common risk factors reported were psychological stress (52%), smoking (38%), arterial hypertension (38%), and a history of or current use of steroids (30%). Most frequently encountered symptoms included decreased visual acuity (76%), metamorphopsia (49%), relative scotoma (47%), blurred vision (19%), and dyschromatopsia (9%). The mean logMAR BCVA on initial examination was 0.2 (≈20/30, IQR 0.2-0.4) but showed significant variation with a tendency of lower BCVA in chronic cases. At the baseline visit, 74% of the overall cohort received no treatment, while 19% underwent local treatment and only 2% underwent systemic treatment. Of the local therapies, anti-VEGF injections were the most frequently performed procedure (33%, mainly for secondary CNV), followed by micropulse laser (28%), focal nonpulsed laser (23%), verteporfin photodynamic therapy (14%), and nonsteroidal anti-inflammatory eye drops (2%). Among intravitreal anti-VEGF agents, aflibercept was used most frequently, followed by bevacizumab and ranibizumab. CONCLUSION: This registry represents one of the largest cohorts of European patients with CSC to date. Patient age and the proportion of women were higher than expected and bilateral active disease was lower than anticipated, highlighting that neither age nor gender should be overemphasized when diagnosing CSC. Therapeutic interventions are heterogeneous and include verteporfin photodynamic therapy, micropulse laser, and anti-VEGF injections in case of secondary CNV.

Intravitreal Injections: Improving Sustainability by Reducing Clinical Waste. / Intravitreale Injektionen: Nachhaltigkeit durch Reduktion von Klinikabfall.

BACKGROUND: Intravitreal injections are one of the most commonly performed ophthalmic procedures. It is estimated that over 1 million intravitreal injections are performed in Germany annually. The aim of this study was to quantify the waste and carbon footprint associated with single-use injection sets, and to establish a waste reduction strategy. MATERIAL AND METHODS: The clinical waste and associated carbon footprint from standard disposable injection sets used by tertiary referral centres in Germany (n = 6) and the United Kingdom (n = 2) were assessed. The safety of performing intravitreal injections with a minimalistic material-sparing approach was evaluated. RESULTS: The average weight of an injection set (and hence the waste generated from each injection) was 165 g. On average, each injection set comprised 145 g (88%) of plastic, 2.1 g (1.3%) of metal, 4.3 g (2.6%) of paper, and 12.9 g (7.8%) of gauze/swabs. The production of such injection sets was extrapolated to a CO2 equivalent of 752.6 tonnes (t), and the incineration of the resulting waste to a CO2 equivalent of 301.7 t. For 1 million injections, this equates to 145.2 t of plastic, 2.1 t of metal, 4.3 t of paper, and 12.9 t of gauze/swabs. A material-sparing approach can reduce injection set-associated waste by 99% without necessarily compromising patient safety. CONCLUSION: A resource-saving approach to intravitreal injections can minimise the generation of clinical waste and its associated carbon footprint, thereby supporting sustainability.

SINGLE-SESSION BILATERAL REDUCED-SETTINGS PHOTODYNAMIC THERAPY FOR BILATERAL CHRONIC CENTRAL SEROUS CHORIORETINOPATHY.

PURPOSE: We performed a multicenter, retrospective study on patients with bilateral chronic central serous chorioretinopathy (cCSC) who received single-session bilateral reduced-settings photodynamic therapy (ssbPDT) and assessed anatomical (resolution of subretinal fluid [SRF]) and functional (best-corrected visual acuity [BCVA]) outcomes and safety. METHODS: Patients who underwent ssbPDT between 01/01/2011 and 30/09/2022 were included. The resolution of SRF at first, second, and final follow-up was assessed on optical coherence tomography (OCT), and BCVA measurements were collected at these visits. When fovea-involving ssbPDT was performed, ellipsoid zone (EZ) and external limiting membrane (ELM) integrity was graded before and after treatment. RESULTS: Fifty-five patients were included in this study. Sixty-two of hundred and eight eyes (56%) showed a complete resolution of SRF at the first follow-up, which increased to 73/110 (66%) at the final follow-up. The mean logMAR BCVA improved by -0.047 ( P = 0.02) over follow-up. EZ integrity increased from 14/21 (67%) to 24/30 (80%) while ELM integrity increased from 22/30 (73%) to 29/30 (97%). CONCLUSION: Patients with cCSC with bilateral SRF at baseline showed significant anatomical and functional improvements after ssbPDT, both at short-term and long-term follow-up. No relevant adverse events were noted.

Usher syndrome type IV: clinically and molecularly confirmed by novel ARSG variants.

Usher syndrome (USH) is an autosomal recessively inherited disease characterized by sensorineural hearing loss (SNHL) and retinitis pigmentosa (RP) with or without vestibular dysfunction. It is highly heterogeneous both clinically and genetically. Recently, variants in the arylsulfatase G (ARSG) gene have been reported to underlie USH type IV. This distinct type of USH is characterized by late-onset RP with predominantly pericentral and macular changes, and late onset SNHL without vestibular dysfunction. In this study, we describe the USH type IV phenotype in three unrelated subjects. We identified three novel pathogenic variants, two novel likely pathogenic variants, and one previously described pathogenic variant in ARSG. Functional experiments indicated a loss of sulfatase activity of the mutant proteins. Our findings confirm that ARSG variants cause the newly defined USH type IV and support the proposed extension of the phenotypic USH classification.

Identification of hydroxyapatite spherules provides new insight into subretinal pigment epithelial deposit formation in the aging eye.

Accumulation of protein- and lipid-containing deposits external to the retinal pigment epithelium (RPE) is common in the aging eye, and has long been viewed as the hallmark of age-related macular degeneration (AMD). The cause for the accumulation and retention of molecules in the sub-RPE space, however, remains an enigma. Here, we present fluorescence microscopy and X-ray diffraction evidence for the formation of small (0.5-20 µm in diameter), hollow, hydroxyapatite (HAP) spherules in Bruch's membrane in human eyes. These spherules are distinct in form, placement, and staining from the well-known calcification of the elastin layer of the aging Bruch's membrane. Secondary ion mass spectrometry (SIMS) imaging confirmed the presence of calcium phosphate in the spherules and identified cholesterol enrichment in their core. Using HAP-selective fluorescent dyes, we show that all types of sub-RPE deposits in the macula, as well as in the periphery, contain numerous HAP spherules. Immunohistochemical labeling for proteins characteristic of sub-RPE deposits, such as complement factor H, vitronectin, and amyloid beta, revealed that HAP spherules were coated with these proteins. HAP spherules were also found outside the sub-RPE deposits, ready to bind proteins at the RPE/choroid interface. Based on these results, we propose a novel mechanism for the growth, and possibly even the formation, of sub-RPE deposits, namely, that the deposit growth and formation begin with the deposition of insoluble HAP shells around naturally occurring, cholesterol-containing extracellular lipid droplets at the RPE/choroid interface; proteins and lipids then attach to these shells, initiating or supporting the growth of sub-RPE deposits.

Critical role of platelet glycoprotein ibα in arterial remodeling.

OBJECTIVE: Arteriogenesis is strongly dependent on the recruitment of leukocytes, especially monocytes, into the perivascular space of growing collateral vessels. On the basis of previous findings that platelets are central players in inflammatory processes and mediate the recruitment of leukocytes, the aim of this study was to assess the role of platelets in a model of arterial remodeling. APPROACH AND RESULTS: C57Bl6 wild-type mice, IL4-R/Iba mice lacking the extracellular domain of the glycoprotein Ibα (GPIbα) receptor, and mice treated with antibodies to block GPIbα or deplete circulating platelets were studied in peripheral arteriogenesis. Using a novel model of intravital 2-photon and epifluorescence imaging, we visualized and quantified the interaction of platelets with leukocytes and the vascular endothelium in vivo. We found that transient platelet adhesion to the endothelium of collateral vessels was a major event during arteriogenesis and depended on GPIbα. Furthermore, leukocyte recruitment was obviously affected in animals with defective platelet GPIbα function. In IL4-R/Iba mice, transient and firm leukocyte adhesion to the endothelium of collateral vessels, as well as leukocyte accumulation in the perivascular space, were significantly reduced. Furthermore, we detected platelet-leukocyte aggregates within the circulation, which were significantly reduced in IL4-R/Iba animals. Finally, platelet depletion and loss of GPIbα function resulted in poor reperfusion recovery as determined by laser Doppler imaging. CONCLUSIONS: Thus, GPIbα-mediated interactions between platelets and endothelial cells, as well as leukocytes, support innate immune cell recruitment and promote arteriogenesis-establishing platelets as critical players in this process.