Search Results (241)

Visual performance (VP) models have played a foundational role in architectural lighting design, informing illuminance standards intended to support safety, efficiency, and task performance across diverse occupant populations. This paper provides a critical historical review of VP models, tracing their development from early retinal response research and threshold visibility functions to contemporary applications in lighting standards. Key physiological and perceptual factors, including retinal illuminance, contrast, task size, and observer characteristics such as age, are examined through landmark studies that shaped suprathreshold VP modeling. Attention is given to the evolution and adoption of the Relative Visual Performance (RVP) model, which remains central to current Illuminating Engineering Society (IES) illuminance recommendations. The review further synthesizes theory-based, applied, and human-centered experimental approaches, highlighting how VP research expanded to include reaction time, reading performance, chromatic contrast, spectral power distribution, mesopic vision, and virtual reality environments. Despite this extensive body of work, VP models have seen limited revision in response to advances in lighting technology, digital displays, and LED spectral control. Based on gaps identified in prior research, this paper proposes a future modeling framework using linear mixed-effects models to independently assess and assign weights to factors influencing VP. Such an approach may support updated illuminance standards better aligned with modern lighting conditions, occupant needs, and energy efficiency goals. Full article

Background: Neovascular age-related macular degeneration (nAMD) remains a leading cause of irreversible central vision loss. Although anti-vascular endothelial growth factor (anti-VEGF) therapy has transformed management, pivotal trials enrolled exclusively treatment-naïve patients, leaving clinicians without pooled evidence to guide switching decisions in previously treated eyes. This systematic review and meta-analysis assessed real-world visual, anatomical, durability, and safety outcomes following switching to aflibercept 8 mg in previously treated nAMD. Methods: Following PRISMA 2020 guidelines, we searched PubMed, Embase, Web of Science, CENTRAL, Scopus, and Google Scholar through April 2026. Studies reporting switching to aflibercept 8 mg with change in best-corrected visual acuity (BCVA), central subfield thickness (CST), or treatment interval were included. Continuous outcomes were pooled using random-effects models with Hartung–Knapp–Sidik–Jonkman adjustment; proportions were estimated using generalized linear mixed models. Methodological quality was evaluated using the JBI Critical Appraisal Checklist for Case Series. Certainty of evidence was assessed using GRADE. The protocol was registered with PROSPERO (CRD420261371334). Results: Twenty-one studies met inclusion criteria. BCVA remained stable (WMD: −0.017 logMAR; 95% CI: −0.027 to −0.007; +0.83 ETDRS letters; I² = 0%). CST decreased significantly (WMD: −21.5 µm; 95% CI: −29.3 to −13.7; I² = 56.0%), and treatment intervals extended by +1.79 weeks (95% CI: +1.32 to +2.27; I² = 74.3%). Intraretinal and subretinal fluid each resolved in 37.5% of eyes. Intraocular inflammation was rare across 9959 treated eyes, though this pool was not restricted to switched eyes, with no confirmed retinal vasculitis. Sensitivity analyses confirmed robustness across all co-primary estimates. GRADE certainty was low for BCVA and very low for CST and treatment interval. Conclusions: Low-certainty evidence suggests that switching to aflibercept 8 mg preserves visual acuity, while very-low-certainty evidence suggests reductions in central subfield thickness and modest extension of treatment intervals. Intraocular inflammation was rare, though safety denominators included non-switch eyes. These findings provide preliminary pooled estimates to inform switch decisions in previously treated eyes. Full article

Current treatments for choroidal neovascularization (CNV) and its associated subretinal fibrosis (SRF), major causes of vision loss, are limited by the need for frequent intravitreal injections and the emergence of drug resistance. This study evaluated the safety and efficacy of the intravitreal administration of engineered humanized anti-vascular endothelial growth factor Nanobodies, including a wild-type Nanobody (WHNb) and two mutated variants (MHNb136 and MHNb256), in a rat model of laser-induced CNV and associated SRF. Safety was assessed through in vivo electrophysiological and histopathological analyses following intravitreal injection of Nanobodies at doses of 12.5, 25, 50, and 100 µg. Efficacy was evaluated in rat models of laser-induced CNV and SRF using double immunohistochemistry for isolectin B4 and anti-collagen type I on sclerochoroidal flat mounts. Mean CNV and SRF areas in Nanobody-treated groups were compared with those in bevacizumab-treated and sham control groups. None of the Nanobodies showed retinal toxicity in safety assessments. Compared with bevacizumab, MHNb136 and MHNb256 reduced the CNV area by 1.72-fold and 1.8-fold, respectively (both p < 0.0001), whereas WHNb showed an effect nearly identical to that of bevacizumab. In addition, 12.5 µg MHNb136 and 100 µg MHNb256 reduced the SRF area by 1.3-fold (p = 0.047) and 1.6-fold (p = 0.0007), respectively, relative to bevacizumab. For CNV reduction, 12.5 µg MHNb136 was comparable to 25 µg MHNb256; both outperformed bevacizumab. For SRF reduction, 12.5 µg MHNb136 was more effective than bevacizumab and comparable to 100 µg MHNb256. These findings suggest that 12.5 µg MHNb136 may represent a cost-effective bioengineered Nanobody candidate for future clinical studies. Full article

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) and newer dual-incretin therapies have become central to the treatment of diabetes mellitus and obesity, with benefits extending beyond glycemic control. Their expanding use has prompted growing interest in their potential ocular effects. Experimental data support plausible protective mechanisms, including reduction in oxidative stress and neuroprotective effects on retinal and optic nerve tissues. Clinical evidence, however, remains heterogeneous. In diabetic retinopathy, the main concern appears to be transient early worsening associated with rapid glycemic improvement rather than direct retinal toxicity. A potential semaglutide-associated signal for non-arteritic anterior ischemic optic neuropathy has raised concern, although the absolute risk appears low and causality remains unproven. Emerging studies also suggest possible beneficial associations with glaucoma, ocular surface diseases, and certain retinal vascular outcomes, whereas the evidence regarding age-related macular degeneration and cataract remains conflicting or preliminary. Overall, ocular outcomes associated with incretin-based therapies seem to reflect a complex interplay among drug-specific pharmacology, systemic metabolic changes, and individual patient susceptibility rather than a class effect. Baseline ophthalmic assessment and individualized follow-up may be advisable in selected high-risk patients. Further prospective ophthalmology-focused studies are needed to clarify long-term safety and identify the patients most likely to benefit or develop adverse events. Full article

Background: Retinal vascular diseases, including neovascular age-related macular degeneration (nAMD), diabetic macular edema (DME), retinal vein occlusion (RVO), and myopic choroidal neovascularization (mCNV), often require repeated intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy. Although ranibizumab is well established, long-term affordability remains challenging. Objective: To compare the functional, anatomical, treatment-burden, and safety outcomes of biosimilar ranibizumab (Ranieyes) and innovator ranibizumab (Lucentis/Accentrix) in routine clinical practice. Methods: This multicenter retrospective comparative study included 4997 eyes from 3577 patients treated across five tertiary eye-care centers in India. The biosimilar group comprised 2543 eyes from 1812 patients (10,893 injections), and the innovator group comprised 2454 eyes from 1765 patients (10,136 injections). Eligible indications were nAMD, DME, BRVO, CRVO, mCNV, and an exploratory miscellaneous preoperative adjunct subgroup. BCVA (logMAR), central subfield thickness (CST; µm), injection burden, and ocular/systemic adverse events were assessed over 24 months. Results: Both groups showed early improvement in BCVA and CST across the major disease categories, followed by long-term stabilization. Between-group differences were generally small, not sustained over follow-up, and of limited clinical magnitude. Serious ocular and systemic adverse events were rare in both groups, and no new safety signal emerged. Conclusions: In this large real-world cohort, the biosimilar ranibizumab Ranieyes showed outcomes broadly comparable to innovator ranibizumab across the major retinal disease subgroups, although these findings should be interpreted as observational comparative evidence rather than formal proof of equivalence. Full article

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have revolutionized the management of type 2 diabetes mellitus (T2DM) by providing robust glycemic control alongside significant cardioprotective and renoprotective benefits. This review synthesizes current mechanistic, preclinical, and clinical evidence regarding the impact of GLP-1RAs on retinal microvasculature and summarizes the current clinical evidence of GLP-1RA-induced retinal complications. GLP-1RAs exert pleiotropic effects on the retinal microvasculature, offering protection by amelioration of endothelial function, reduction in oxidative stress, inflammation, microvascular remodeling, and preservation of the blood–retinal barrier (BRB). Despite these mechanistic advantages, emerging clinical data have raised concerns regarding potential retinal adverse events associated with GLP-1RA therapy. Observational studies and pharmacovigilance analyses have suggested possible associations with non-arteritic anterior ischemic optic neuropathy (NAION), diabetic macular edema (DME), vitreous hemorrhage, retinal detachment, macular hole formation, and progression of diabetic retinopathy (DR), particularly in the context of semaglutide use. Most evidence comes from retrospective studies or secondary endpoints, limiting causal inference. Retinal complications associated with GLP-1RAs remain heterogeneous and inconclusive, requiring careful evaluation of potential risks across diverse patient populations. Future research should conduct large, randomized trials with standardized ocular endpoints, detailed imaging, and stratified analyses to clarify GLP-1RA retinal safety. Full article

Background/Objectives: Central retinal artery occlusion (CRAO) is a vision-threatening condition with limited evidence-based treatment options. Hyperbaric oxygen therapy (HBOT) has emerged as a potential intervention, but its efficacy remains debated. This systematic review and meta-analysis evaluated the therapeutic efficacy and safety of HBOT in CRAO. Methods: Relevant studies were identified across seven databases using optimized Boolean and MeSH-based strategies. Eligible studies evaluated HBOT in CRAO and reported visual or safety outcomes. Extracted data included demographics, intervention details, treatment timing, visual acuity outcomes, and adverse events. Risk of bias was assessed using ROBINS-I. Visual acuity outcomes were standardized to logMAR whenever directly reported or convertible, and subgroup analyses were stratified by HBOT initiation time (<12 h vs. >12 h), study type, and baseline visual severity when reported. A random-effects model was used, and pooled estimates were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). Results: Twelve studies were included. The pooled efficacy analysis favored HBOT (OR = 0.47; 95% CI: 0.26–0.87; p = 0.02), although heterogeneity was substantial (Tau² = 0.64; I² = 78%). Stratified synthesis showed that studies in which HBOT was initiated within 12 h consistently reported greater visual improvement, whereas delayed or variably timed treatment showed attenuated and inconsistent benefits. After outcome harmonization, studies reporting logMAR-compatible data generally demonstrated clinically relevant visual improvement, while adverse-event rates did not differ significantly between HBOT and non-HBOT groups (OR = 0.70; 95% CI: 0.43–1.16; p = 0.17; I² = 0%). Conclusions: HBOT appears most beneficial when initiated early, particularly within the first 12 h. However, heterogeneity in treatment timing, study design, and baseline severity reporting limits the certainty of these results and supports the need for standardized outcome reporting and protocol-driven prospective studies. Full article

Purpose: To evaluate the 3-year effectiveness and safety of the XEN63 Gel Stent, both as a standalone procedure and combined with phacoemulsification, in patients with primary open-angle glaucoma (POAG). Methods: This prospective, multicenter, non-randomized study included 85 eyes (85 patients) with medically-uncontrolled POAG. Subjects underwent either XEN63-standalone implantation (n = 46) or combined XEN63 + Phacoemulsification (n = 39). The primary endpoint was the cumulative probability of complete success (IOP ≥ 6 and ≥18 mmHg and reduction in IOP ≥ 20% from baseline without ocular-hypotensive medications) at 36 months. Results: At 36-months, the overall surgical success rate was 67.1% (95% CI: 50.8–86.9%), with significant differences between the standalone (78.3%) and combined groups (53.9%; p = 0.0173). Complete success was achieved in 45.9% of the total cohort. Preoperative mean IOP decreased significantly from 21.3 ± 4.7 mmHg to 14.3 ± 4.3 mmHg at the last-follow-up visit (LFUV) (p < 0.0001). Correspondingly, the mean number of medications was significantly reduced from 2.3 ± 0.8 to 0.7 ± 1.0 (p < 0.0001). Multivariable analysis showed that surgical strategy did not significantly influence IOP reduction. Numerical hypotony (IOP < 6 mmHg) occurred in 23.5% of eyes at Day 1 but resolved in 95% of cases by Month 1. One case of hypotonic maculopathy required device explantation. Serious late-onset events included one endophthalmitis (Month 30) and one retinal detachment (Month 26). Secondary needling was required in 8.2% of eyes. Conclusions: The XEN63 Gel Stent provided sustained IOP reduction and a significantly decreased medication burden over 36 months. Outcomes remained consistent regardless of whether the stent was implanted as a standalone procedure or combined with cataract surgery. Full article

Background/Objectives: This study analyzed intraoperative parameters, structural safety, and morphofunctional outcomes of vitreoretinal procedures performed using a conventional operating microscope versus a three-dimensional (3D) heads-up digital visualization system. Methods: A retrospective single-surgeon case series included 248 eyes undergoing pars plana vitrectomy for epiretinal membrane (ERM), macular hole (MH), or rhegmatogenous retinal detachment (RRD). Patients were divided into conventional microscope (n = 122) and 3D heads-up (n = 126) groups. Primary outcomes included surgical duration, endoillumination intensity, best-corrected visual acuity (BCVA), anatomical success, and complications over a 6-month follow-up. Results: The 3D cohort showed a significantly shorter global median surgical duration (50.0 vs. 60.0 min, p = 0.001). Multivariate regression confirmed the 3D system as an independent predictor of shorter operative time globally (p = 0.011). After adjusting for baseline disease severity imbalances in the ERM subgroup, the 3D system maintained an independent reduction in surgical duration of 5.5 min (p = 0.044). The 3D system also required significantly lower endoillumination across all procedures (p ≤ 0.002). Anatomical success rates were high and comparable across indications. Both groups achieved similar and significant visual improvement at 6 months (p = 0.120). Structural safety biomarkers (SANFL, DONFL) and complication rates remained comparable. Conclusions: The 3D heads-up visualization system demonstrated comparable functional and anatomical outcomes to conventional microscopy across standard vitreoretinal procedures. It allows for surgery under significantly lower light conditions and demonstrates the potential to optimize operative time, particularly in ERM peeling. Furthermore, it maintains an equivalent structural safety profile to conventional surgery. Full article

Retinopathy of Prematurity (ROP) affects preterm infants worldwide, involving abnormal development of retinal blood vessels associated with supplemental oxygen use in neonatal care. Although there have been strides in identifying at-risk infants, implementing early screening, updating disease criteria through the International Classification of Retinopathy of Prematurity (ICROP), and developing new therapies, ROP remains a leading cause of preventable blindness. As preterm birth survival rates rise, the incidence of ROP continues to increase and is projected to rise even in countries with abundant resources and well-established care programs. Improving ROP care requires global standardization of screening, diagnosis, and management to prevent missed diagnoses and minimize outcome variability. Intravitreal anti-vascular endothelial growth factor (VEGF) injections are changing the landscape of ROP management, but longitudinal research is needed to determine their long-term safety in preterm infants. Effective ROP management relies on teamwork across disciplines and open communication with parents. Given that parents are lifelong caregivers of a child who may be affected by ROP-related vision impairment, including them in the care team and encouraging psychosocial support is vital. Socioeconomic disparities and limited access to ROP-trained ophthalmologists exacerbate disease burden, underscoring the need for innovative solutions to improve access to care. This perspective emphasizes the importance of globally standardizing ROP prevention and care, noting that efforts are still incomplete, equitable access has not been realized, and the long-term role of anti-VEGF agents in ROP treatment remains unclear. Full article

Purpose: To evaluate the safety and feasibility of repeated subtenon administration of autologous platelet-rich plasma (PRP) in patients with degenerative retinal diseases and to explore preliminary, hypothesis-generating functional observations in retinitis pigmentosa (RP) and extensive macular atrophy with pseudodrusen-like appearance (EMAP). Methods: This prospective, open-label, uncontrolled pilot study included 13 patients (6 RP, 7 EMAP) who received three subtenon PRP injections (1.5 mL each) at baseline, Month 2, and Month 4, with follow-up through Month 6. The study was designed primarily to assess safety and feasibility and was not powered or intended to evaluate efficacy. The primary outcome was safety, including adverse events and intraocular pressure changes. Exploratory secondary outcomes included best-corrected visual acuity (BCVA, logMAR), visual field mean deviation (MD), and structural optical coherence tomography (OCT) parameters. Electrophysiological outcomes were analyzed descriptively due to incomplete paired data. Analyses were conducted within diagnostic groups, and no between-group comparisons were performed. Results: All 13 patients completed the study. No serious adverse events or permanent ocular morbidity were observed. Two transient and self-limited adverse events occurred (anterior uveitis and intraocular pressure elevation), both resolving without sequelae. In the overall cohort, BCVA remained stable without statistically significant change. In the RP subgroup, a small exploratory change in BCVA was observed (mean ΔlogMAR −0.09; nominal p = 0.048), corresponding to approximately 4–5 ETDRS letters; however, this finding was associated with wide confidence intervals and limited statistical power and should be interpreted cautiously. In the EMAP subgroup, functional stability was observed without evidence of consistent improvement. Visual field mean deviation and OCT findings were consistent with absence of short-term deterioration across available paired data. Electrophysiological outcomes showed no consistent directional change. Conclusions: Repeated subtenon PRP administration appeared feasible and well tolerated in this small, uncontrolled pilot cohort. Any observed functional changes are preliminary and hypothesis-generating only and do not establish efficacy. Larger, adequately powered controlled studies with standardized endpoints are required to determine the potential role of PRP in degenerative retinal diseases. Full article

Background and Objectives: Myopic choroidal neovascularization (mCNV) is a vision-threatening complication of pathologic myopia. While anti-VEGF monotherapy is the current standard of care, recurrence and suboptimal responses remain challenges. Faricimab is a novel bispecific antibody that targets both vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang-2) to improve vascular stability. This study aims to evaluate the short-term efficacy and safety of a single intravitreal faricimab injection in eyes with active mCNV. Materials and Methods: This retrospective, single-center study included 27 eyes from 24 patients with active mCNV, including both treatment-naïve and previously treated cases. All eyes received a single intravitreal injection of faricimab (6.0 mg/0.05 mL). Best-corrected visual acuity (BCVA) in logMAR and central retinal thickness (CRT) via spectral-domain optical coherence tomography were assessed at baseline and one month post injection. Statistical significance was determined using paired and independent t-tests (p < 0.05). Results: The study population (mean age 55.5 ± 13.9 years; mean axial length 29.3 ± 1.6 mm) showed significant improvements at one month. Mean BCVA improved from 0.77 ± 0.71 logMAR to 0.51 ± 0.52 logMAR (p < 0.005). Mean CRT decreased from 290.2 ± 66.0 μm to 242.5 ± 45.7 μm (p < 0.005). No ocular adverse events, such as intraocular inflammation, retinal detachment, or endophthalmitis, were observed. Conclusions: A single intravitreal injection of faricimab provides significant short-term functional and anatomical improvement in this small retrospective series. Dual inhibition of VEGF-A and Ang-2 appears to be a safe and effective approach for stabilizing retinal vasculature in patients with high myopia. Larger, long-term prospective studies are needed to determine optimal treatment intervals for mCNV. Full article

Diabetic retinopathy (DR) is a common cause of vision loss in diabetes, and it often progresses without early symptoms. DR reflects injury of the retinal neurovascular unit (NVU), which includes neurons, Müller glia, astrocytes, endothelial cells, pericytes, and immune cells. Chronic hyperglycemia drives oxidative stress, advanced glycation end products–receptor for advanced glycation end products (AGE–RAGE) signaling, mitochondrial injury, and low-grade inflammation. These changes disrupt endothelial junctions, promote leukostasis, weaken pericyte support, increase basement membrane thickening, and lead to capillary dropout and hypoxia. Hypoxia-related signaling increases anti-vascular endothelial growth factor (VEGF) activity, which raises vascular leakage and supports neovascular disease. Glial stress and microglial activation add cytokines and reactive oxygen species, and neural dysfunction can appear early and can weaken neurovascular coupling. Modern diabetes care changes the short-term risk landscape because potent therapies can lower HbA1c quickly. Large and rapid HbA1c reductions can trigger early worsening of diabetic retinopathy (EWDR), mainly in patients with high baseline HbA1c and moderate-to-severe baseline DR. Semaglutide’s retinopathy complication signal in SUSTAIN-6 fits an EWDR-like pattern that tracks with rapid glycemic improvement in vulnerable eyes. In parallel, surgery adds acute stress, inflammation, glucose swings, hemodynamic shifts, and medication interruptions. These factors can worsen microvascular instability during recovery. Current perioperative guidelines and regulatory recommendations describe glucose targets and medication safety considerations, including preoperative interruption of SGLT2 inhibitors to reduce euglycemic ketoacidosis risk; however, the retina-specific implications of these measures remain indirect. This review summarizes current evidence linking NVU biology, EWDR risk, and perioperative diabetes-related factors. It discusses how these factors may interact in patients with diabetes and how they may influence retinal outcomes. The review is intended to synthesize current evidence and mechanistic interpretations rather than to provide formal clinical practice recommendations. Full article

Background: A novel titanium scleral buckle implant (TSBI) was developed for the treatment of posterior pole retinal detachments, analytically modeled and structurally tested as part of preclinical approval studies. The strength and stiffness requirements to apply pressure for retinal reattachment also suggested potential benefits for correcting high myopia greater than 8 diopters. Methods: Laboratory load testing and analytical calculations were complemented by nonlinear finite element modeling (FEM), applied for the first time to capture the interaction between the highly deformed myopic eye and the TSBI. Simulations were used to visualize posterior pole indentation and force distribution across anatomical regions. Seven TSBI units were tested in the transverse direction and six in the longitudinal direction. Results: The simulations confirmed that stable indentation is maintained even in areas distant from the sutures. The TSBI’s minimum midspan bending capacity was 40 N at yield and 60 N at ultimate. These values, together with FEM predictions, demonstrated a very large safety margin and showed that the implant deforms insignificantly under high intraocular pressure changes. Conclusions: The TSBI withstands ocular forces, cushions the sclera safely, and retains its geometry, a behavior that may differ from softer buckle materials, which can exhibit time-dependent deformation under sustained loading. Early controlled clinical applications outside the USA, followed for over three years, further validate its safety and potential effectiveness. Full article

Purpose: Evidence on the safety of single-joint isometric exercises of the lower legs remains limited. Thus, the aims of this study were to examine intraocular pressure (IOP) and retinal vessel responses during a 1 min isometric knee extension task and to assess potential sex-related differences. Materials and Methods: This prospective, parallel-group, quasi-experimental exploratory trial enrolled 43 healthy young adults (22 males and 21 females; age range: 19–35 years), who performed a 1 min sustained maximal-effort isometric knee extension task. The cardiovascular response, IOP, and retinal vessel diameters were assessed. Results: The isometric task increased fatigue, heart rate, systolic blood pressure (SBP), and mean arterial pressure in both sexes (p < 0.05), with males exhibiting a significantly greater rise in SBP than females (p < 0.05). A significant reduction in IOP was observed only in males (p < 0.05). Central retinal arteriolar equivalent decreased in both sexes (p < 0.05), whereas central retinal venular equivalent (CRVE) increased exclusively in females (p < 0.05). Despite the difference in the CRVE response, both sexes exhibited a comparably reduced arteriolar-to-venular diameter ratio (p < 0.05). Conclusions: To sum up, the isometric maximal-effort knee extension exercise increased cardiovascular loads in both sexes, with males showing a greater SBP rise and a reduction in IOP. Although retinal microvascular responses were sex specific, both sexes showed a similar reduction in the arteriolar-to-venular diameter ratio, indicating a consistent shift in microvascular regulation. Full article