Search Results (119)

Corneal defects are a major cause of vision loss and require rapid, biocompatible, and effective sealing methods to restore ocular integrity and prevent infection. Current clinical adhesives, such as cyanoacrylate and fibrin glue, are limited by problems such as poor biocompatibility and inadequate stability. This study presents the design and evaluation of a fast-curable polymer bioadhesive hydrogel, a corneal glue formulated for efficient sealing of corneal defects. Hydrogels were synthesized from natural and synthetic polymers, including polyvinyl alcohol (PVA), sodium alginate (SA), and carboxymethyl cellulose (CMC), optimized for rapid gelation (~45 s), robust adhesion (~15 kPa), and mechanical strength (tensile strength ~0.35 MPa and storage modulus G′ indicating strong elastic behavior). Physicochemical and rheological properties, including swelling behavior and optical transparency (>90% transmittance across 400–700 nm), were characterized, including gelation time, swelling behavior, and mechanical strength. In vitro biocompatibility was assessed using human corneal epithelial cells to evaluate cytotoxicity and cell adhesion. Ex vivo studies on human cadaveric corneas with full-thickness defects measured adhesive strength and sealing efficacy through burst pressure (~38 mmHg) and leakage tests, with comparisons to commercial fibrin and cyanoacrylate adhesives. The optimized corneal glue exhibited fast curing, robust adhesion, high water retention with minimal swelling, favorable viscoelastic properties, and excellent cytocompatibility effectively sealing corneal defects in ex vivo models. These results highlight its potential as a promising fast-curable bioadhesive for corneal wound repair and ocular surface restoration. Full article

Background/Objectives: The ocular surface is continuously exposed to microorganisms, and disruption of host–microbial balance may lead to infection or postoperative complications. Increasing antimicrobial resistance and biofilm formation have highlighted the need for alternative or complementary non-antibiotic strategies to control ocular surface microbial burden. Liposomal ozonated oil eyedrops have demonstrated antimicrobial and antibiofilm activity in preclinical and preliminary clinical studies. The aim of this study was to evaluate changes in ocular surface microbiological culture results before and after treatment with liposomal ozonated oil eyedrops in a real-world clinical setting. Methods: This was a prospective, observational, real-world pre–post study including 101 eyes from 101 patients undergoing ocular surface microbiological sampling in routine clinical practice. Two samples were obtained per patient: Sample I immediately before treatment and Sample II at the routine follow-up visit after short-course treatment with liposomal ozonated oil eyedrops (1 drop, four times daily, for 4 days). The interval between samples ranged from 3 to 5 days (median 3 days). Microbiological cultures were classified as positive or showing no growth. Paired changes in culture positivity were analyzed using McNemar’s exact test. Results: At baseline, 87 of 101 samples (86.1%) yielded positive cultures, while 14 (13.9%) showed no growth. Following treatment, culture positivity decreased to 11 of 101 samples (10.9%), with 90 samples (89.1%) showing no growth. Among baseline-positive samples, microbiological clearance was observed in 76 cases (87.4%). No cases converted from culture-negative to culture-positive at follow-up. The reduction in culture positivity after treatment was statistically significant (McNemar’s exact test, p < 0.001). Recent antibiotic exposure within 14 days prior to baseline sampling was reported in 8 patients (7.9%). Persistent positive cultures were observed in a minority of cases and were mainly associated with common ocular surface pathogens. Conclusions: In routine clinical practice, short-term treatment with liposomal ozonated oil eyedrops was associated with a significant reduction in ocular surface culture positivity over a short follow-up interval. Full article

The ocular surface is a neuro–epithelial–immune unit in which corneal innervation is essential for maintaining tissue integrity and visual function. Sensory nerves regulate reflex tearing and blinking, provide trophic support, and modulate local immune responses. Nerve injury resulting from trauma, surgery, infection, systemic disease, or chronic inflammation disrupts epithelial homeostasis and may lead to neurotrophic keratopathy, neuropathic pain, and pathological remodeling. Beyond classical neurotrophic disease, nerve dysfunction contributes to severe dry eye and immune-mediated cicatricial disorders. Depending on the neuro-inflammatory context, remodeling may evolve toward stromal thinning, as in keratoconus, or progressive fibrosis, as in ocular cicatricial pemphigoid. Blood-derived eye drops, including serum- and platelet-based formulations, represent biologically active therapies that support epithelial repair and nerve regeneration, although greater standardization is needed. Full article

The ocular surface microbiome plays a critical role in maintaining ocular health, preventing infections, and regulating immune responses. Contact lens (CL) wear has been linked to alterations in microbial composition, potentially leading to dysbiosis and increased susceptibility to ocular infections. This review aims to summarize current evidence on the effects of CL use on the ocular microbiome and to discuss strategies to preserve microbial homeostasis. A literature search was conducted in PubMed, Scopus, Web of Science, and Google Scholar for English-language human studies published between January 2005 and January 2025. We included original studies and systematic reviews evaluating the ocular surface bacterial community in contact lens (CL) wearers using either sequencing-based approaches (microbiome; e.g., 16S rRNA gene sequencing/metagenomics) or culture-based methods (microbiota). Two authors screened titles/abstracts and full texts. Overall, 12 studies met the inclusion criteria and were qualitatively synthesized. Across included studies, CL wear was associated with reproducible changes in the ocular surface bacterial community, most commonly a shift toward a skin-like profile and increased detection/relative abundance of opportunistic taxa (e.g., Pseudomonas, Acinetobacter, and Staphylococcus aureus) together with reduced representation of typical ocular commensals in several sequencing-based datasets. Culture-based studies reported increased recovery of opportunistic bacteria from lenses and storage cases, supporting contamination/biofilm-related mechanisms. Lens care solutions and preservatives were reported to modulate bacterial profiles and may contribute to dysbiosis, although evidence remains heterogeneous across study designs and analytic pipelines. CL use is associated with significant alterations in the ocular microbiome, increasing the risk of microbial keratitis and corneal inflammatory events. Strategies to maintain microbial balance, including careful selection of lens care products and development of antimicrobial lenses, may improve ocular surface health in CL wearers. Future longitudinal studies with standardized sampling and analytic workflows are needed to clarify causal links between CL-associated microbial changes and clinical outcomes. Full article

Background/Objectives: Conjunctival closure may influence early postoperative comfort and wound healing after pediatric strabismus surgery. We compared fibrin glue with absorbable sutures using anterior segment optical coherence tomography (AS-OCT)-based conjunctival thickness, serial clinical scores, ocular-surface screening, and operative time. Methods: We retrospectively reviewed 82 children (5–15 years) who underwent bilateral medial rectus recession. The conjunctiva was closed with 8-0 polyglactin 910 (Vicryl) (suture group, n = 40) or fibrin glue (fibrin group, n = 42) according to routine practice; right eyes were analyzed. Conjunctival thickness was measured by AS-OCT preoperatively and at week 6. The comfort questionnaire (CQ) score and inflammation score (IS) were recorded on postoperative day 1 and weeks 1, 2, and 6. Total operative time and closure time were obtained from surgical video recordings. Ocular Surface Disease Index-6 (OSDI-6) and non-invasive keratographic break-up time (NIKBUT) were assessed preoperatively and at week 6 in cooperative children (n = 62). Results: Conjunctival thickness increased in both groups and was slightly higher at week 6 with sutures (p < 0.001), with a slightly greater percentage increase (p = 0.001). CQ and IS were worse with sutures through week 2 (all p < 0.05) and converged by week 6 (both p > 0.05). Fibrin glue shortened total operative time (32.75 vs. 35.46 min; p < 0.05) and closure time (3.90 vs. 5.35 min; p < 0.001). In the ocular-surface subset, OSDI-6 and NIKBUT did not differ between groups at week 6. No infections or granulomas occurred; two early conjunctival wound gaps occurred in the fibrin group and one resolved with topical management, while the other met the dehiscence definition (≥2 mm) and required re-suturing, and both healed without sequelae. Conclusions: In pediatric strabismus surgery, fibrin glue demonstrated better early comfort with a modest difference in conjunctival thickness at week 6 along with slightly shorter operative time while clinical scores converged by week 6, and ocular-surface screening outcomes were similar. Full article

Background/Objectives: Keratitis is an ocular disease caused by microbial infection or by non-infectious damage due to UV light exposure, chemical exposure, or eye injuries. Methods: Moxifloxacin-loaded ufasomes (MOX-UFAs) were optimized using a full factorial design (1².2³) after being prepared by the vortex mixing method. The study evaluated the effects of the oleic acid amount, surface active agent (SAA) amount, and SAA type as independent factors on the entrapment efficiency percent (EE%), particle size (PS), polydispersity index (PDI), zeta potential (ZP), and the amount released after 6 h (Q6h%). Results: The optimized ufasomes (UFAs) formulation was spherical, with an EE% of 78.37 ± 3.91%, PS of 203.13 ± 20.31 nm, PDI of 0.334 ± 0.016, and ZP of −25.42 ± 1.27 mV. The in vitro release of moxifloxacin (MOX) from the UFAs was maintained for more than 6 h in the range of 40.0–75.0%. The optimum MOX-UFAs formulation was incorporated into an in situ gel (Pluronic F-127/HPMC K4M). The ex vivo studies (corneal permeation and confocal laser scanning microscopy) proved the successful retention of the MOX-UFAs-laden in situ gel. Furthermore, the in vitro and in vivo antimicrobial studies revealed their significant antimicrobial effect against Pseudomonas aeruginosa. In addition, the Draize test proved the tolerability of MOX-UFAs-laden in situ gel in animals. Conclusions: The incorporation of MOX-UFAs into Pluronic F-127/HPMC K4M in situ gel could successfully provide sustained ocular delivery and improve the bioavailability of MOX for the management of keratitis. Full article

Background/Objectives: Post-coronavirus syndrome (long-COVID) refers to a multi-systemic range of symptoms that follows acute SARS-CoV-3 infection. Long-COVID has been linked with autonomic neuropathy as well as dry-eye disease (DED), an umbrella term that includes a variety of ocular symptoms and signs. Despite these associations, little is known about the co-occurrence of DED and dysautonomia symptoms in individuals with long-COVID. This study aims to examine relationships between dysautonomia and ocular symptoms in a long-COVID patient population. Methods: Cross-sectional study of 162 veterans with long-COVID. The Composite Autonomic Symptom Score-31 (COMPASS-31) assessed dysautonomia symptoms, and the NASA lean test and heart-rate variability metrics captured dysautonomia signs. Dry-eye disease (DED) symptoms were measured with the 5-Item Dry-Eye Questionnaire (DEQ5) and the Ocular Surface Disease Index (OSDI), while ocular pain intensity and neuropathic pain descriptors were evaluated using a Numerical Rating Scale (NRS) and select questions from the Neuropathic Pain Symptom Inventory modified for the Eye (NPSI-Eye), respectively. Results: Most participants (78%) reported DED symptoms (DEQ5 ≥ 6). Nearly all COMPASS-31 domains were associated with DED symptoms, with the strongest correlation observed between the OSDI and pupillomotor scores (r = 0.67, p < 0.001). Among the autonomic signs, the strongest associations were observed between the change in systolic and diastolic blood pressure from baseline to 8 min and ocular pain triggered by temperature (r = −0.44 and r = −0.48, respectively, p < 0.01 for both). On linear regression analyses, pupillomotor and secretomotor symptoms remained positively associated with DED symptoms, while autonomic signs were most closely related to ocular pain metrics, with fluctuating blood pressure changes during orthostasis relating to neuropathic symptoms. Conclusions: DED symptoms, including ocular pain intensity, relate to autonomic symptoms in a long-COVID cohort. While associations with autonomic signs were less consistent, these data suggest that subtle autonomic variability relates to ocular pain in the long-COVID setting. Full article

Antimicrobial resistance (AMR) is a growing global health concern with profound implications for ophthalmology, where it compromises the management of ocular infections such as bacterial keratitis, conjunctivitis, endophthalmitis, and postoperative complications. Resistance in common ocular pathogens, including Staphylococcus aureus (S. aureus), Streptococcus pneumoniae (S. pneumoniae), Pseudomonas aeruginosa (P. aeruginosa), and coagulase-negative staphylococci (CoNS) emerge through genetic mutations, horizontal gene transfer, and biochemical mechanisms such as enzymatic degradation, target modification, efflux pumps, and reduced membrane permeability. Biofilm formation further complicates eradication on the ocular surface and interior. The key drivers of resistance include inappropriate or prolonged topical antibiotic use, routine prophylaxis in ocular surgery, subtherapeutic dosing, and cross-resistance with systemic antimicrobials. The rise in multidrug-resistant strains, particularly methicillin-resistant S. aureus, fluoroquinolone-resistant P. aeruginosa, and drug-resistant S. pneumoniae has been linked to delayed treatment response, increased healthcare costs, and sight-threatening outcomes. Recent advances in rapid diagnostics, molecular assays, and point-of-care testing support earlier and more precise detection of resistance, enabling timely therapeutic decisions. Promising strategies to address AMR in ophthalmology include antimicrobial stewardship, novel drug delivery platforms, and alternative approaches such as bacteriophage therapy and antimicrobial peptides. Emerging tools, including genomic surveillance, artificial intelligence (AI)-driven resistance prediction, and personalized antimicrobial regimens, further expand opportunities for innovation. Collectively, this review synthesizes current evidence on AMR in ocular disease, summarizing patterns of resistance, underlying mechanisms, and clinical consequences, while highlighting strategies for mitigation and underscoring the need for global awareness and collaboration among clinicians, researchers, and policymakers to safeguard vision. Full article

Ophthalmic lens coatings are increasingly designed to combine optical, mechanical, and biological functions. This systematic review, registered in PROSPERO and conducted according to PRISMA 2020 guidelines, synthesized 54 experimental, preclinical, and clinical studies on coatings for spectacle lenses, contact lenses, and intraocular lenses. Spectacle lens studies consistently showed that anti-reflective and blue-light filtering coatings reduce glare perception, improve contrast sensitivity, and provide UV protection, while laboratory tests demonstrated significant reductions in impact resistance, with fracture energy of CR-39 lenses decreasing by up to 63% when coated. Contact lens research revealed that plasma and polymeric coatings reduce water contact angles from >100° to <20°, enhancing wettability, while antimicrobial strategies such as melamine binding or nanoparticle-based films achieved >80% reductions in bacterial adhesion. Drug-eluting approaches sustained antibiotic or antioxidant release for periods ranging from 24 h to 6 days, with improved ocular bioavailability compared with drops. Intraocular lens studies demonstrated that heparin surface modifications reduced postoperative flare and anterior chamber cells, and phosphorylcholine or alkylphosphocholine coatings suppressed lens epithelial cell proliferation. Drug-loaded coatings with methotrexate, gefitinib, or amikacin significantly inhibited posterior capsule opacification and infection in ex vivo and animal models. Collectively, coatings improve visual comfort, photoprotection, wettability, and biocompatibility, but clinical translation requires solutions to mechanical trade-offs, long-term stability, and regulatory challenges. Full article

Traditionally used to combat infections, systemic effects of antibiotics are increasingly recognized in the context of absorption through unconventional routes. One such as the ocular surface. This review tackles the bidirectional liver–eye axis, highlighting how trace antibiotic residues from environmental and therapeutic sources affect the tear film, disturb ocular microbiota, and impact liver metabolism. It engages in anatomical pathways, microbial regulation, pharmacokinetics, and systemic immune responses. Additionally, this review discusses forensic uses and new therapeutic strategies, stressing the importance of integrated environmental monitoring and precision medicine to tackle nonmedicinal antibiotic exposure. Due to the absence of results from a systematic literature review, a narrative literature review was undertaken instead. More than 100 studies discussing mechanistic, clinical, and experimental insights were reviewed, with 98 of those studies being documented as source literature. The findings demonstrate that antibiotics may penetrate and be absorbed through the ocular surface, cause modifications of the hepatic first-pass metabolism, and change the activity of cytochrome P450. Correlations were documented between the various liver function biomarkers and the ocular tear film, as well as the thickness of the retinal pigment epithelium. The dysbiosis of eye microbiota may be an indicator of systemic inflammation associated with immune dysregulation. Restoring microbial homeostasis and addressing systemic dysregulation are novel therapeutic approaches, including the use of probiotics, nanoparticle scavengers, and CRISPR. The eye is a sensory organ and a metabolically active organ. Systemically, the eye can affect the liver through the ocular surface and the antibiotics through the liver–eye axis. To protect the systemic health of the individual and the lensed metabolically active eye, the eye and liver must be viewed as a sentinel of systemic balance. Novel therapies will be necessary with the added need for environmental monitoring. Full article

Age-related macular degeneration (AMD) represents a leading cause of irreversible blindness in the elderly, primarily by choroidal neovascularization (CNV) leakage. While intravitreal injections of anti-angiogenic antibodies (e.g., aflibercept) provide clinical benefits, their short half-life necessitates frequent administrations, potentially causing ocular infections or retinal detachment. There is an urgent need for effective antibody delivery systems. Mesoporous silica nanoparticles (MSN) have emerged as promising nanocarriers due to their tunable porosity, surface modifiability, and biocompatibility, though their application in ophthalmology for antibody delivery remains underexplored. We developed two MSN carries: spiky mesoporous silica nanospheres (S-MSN) without amino groups and amine-functionalized hollow dendritic mesoporous silica nanospheres (A-HDMSN). Characterization revealed that A-HDMSN exhibited superior properties, including a larger surface area (550.32 vs. 257.72 m²/g), larger mesoporous pore size (17 vs. <10 nm), and 5.28 times higher drug loading capacity (286.31 ± 8.14 vs. 54.26 ± 3.61 μg/mg) compared to S-MSN (n = 3, p < 0.001), attributable to pore size effects and hydrogen bonding. FITC-labeled A-HDMSN demonstrated efficient uptake by retinal pigment epithelial cells (ARPE-19). Notably, A-HDMSN loaded with Aflibercept (A-HDMSN@Afl) showed significant inhibitory effect on VEGF-induced cell migration even 10 days after drug release in vitro, indicating a favorable sustained-release effect of the drug. These findings highlight A-HDMSN as a promising antibody delivery platform that could extend clinical dosing intervals, offering potential for improved AMD management. Full article

Nowadays, a significant portion of the population uses eye cosmetics, a trend that is not limited to women, as men increasingly adopt stylish makeup techniques. Eye cosmetics, often termed eye makeup, include a diverse array of products such as eyelash enhancers (mascara, false eyelashes, growth serums, and dyes), eyelid products (eyeliner, kohl, eye contour cream, and eyeshadow), and eye makeup removers. There is a persistent interest among dermatologists in the influence of eye cosmetics on the skin surrounding the eye. The formulation of these cosmetics typically consists of various ingredients, some of which may present potential health risks to users. The application of eye cosmetics is linked to a range of adverse effects on the ocular surface, which may manifest as mechanical injury, tear film instability, toxicity, inflammation, and infections. Therefore, the use of cosmetics in this sensitive area is of paramount importance, necessitating a cooperative approach among eyecare professionals, dermatologists, and beauty experts. Despite the widespread use of eye makeup, its possible ocular side effects have not been sufficiently addressed. This report aims to elucidate how the use of eye cosmetics represents a lifestyle challenge that may exacerbate or initiate ocular surface and adnexal disorders. Full article

Microbial biofilms present a formidable challenge in ophthalmology. Their intrinsic resistance to antibiotics and evasion of host immune defenses significantly complicate treatments for ocular infections such as conjunctivitis, keratitis, blepharitis, and endophthalmitis. These infections are often caused by pathogens, including Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans, particularly in patients using contact lenses or intraocular implants—devices that serve as surfaces for biofilm formation. The global rise in antimicrobial resistance has intensified the search for alternative treatment modalities. In this regard, plant-derived antimicrobials have emerged as promising candidates demonstrating broad-spectrum antimicrobial and antibiofilm activity through different mechanisms from those of conventional antibiotics. These mechanisms include inhibiting quorum sensing, disrupting established biofilm matrices, and interfering with microbial adhesion and communication. However, the clinical translation of phytochemicals faces significant barriers, including variability in chemical composition due to environmental and genetic factors, difficulties in standardization and reproducibility, poor water solubility and ocular bioavailability, and a lack of robust clinical trials evaluating their efficacy and safety in ophthalmic settings. Furthermore, regulatory uncertainties and the absence of unified guidelines for approving plant-derived formulations further hinder their integration into evidence-based ophthalmic practice. This review synthesizes the current knowledge on the pathogenesis and treatment of biofilm-associated ocular infections, critically evaluating plant-based antimicrobials as emerging therapeutic agents. Notably, resveratrol, curcumin, abietic acid, and selected essential oils demonstrated notable antibiofilm activity against S. aureus, P. aeruginosa, and C. albicans. These findings support the potential of phytochemicals as adjunctive or alternative agents in managing biofilm-associated ocular infections. By highlighting both their therapeutic promise and translational limitations, this review contributes to the ongoing discourse on sustainable, innovative approaches to managing antibiotic-resistant ocular infections. Full article

The therapeutic potential of exosomes (Exos), a subpopulation of extracellular vesicles (EVs) secreted by various cell types, has been broadly emphasized. Exos are endosome-derived membrane-bound vesicles 50–150 nm in size. Exos can be general or cell type-specific. Their contents enable them to function as multi-signaling and vectorized vehicles. Exos are important for maintaining cellular homeostasis. They are released into extracellular spaces, leading to uptake by neighboring or distant cells and delivering their contents to modulate cell signaling. Exos influence tissue responses to injury, infection, and disease by fusion with the target cells and transferring their cargo, including cytokines, growth and angiogenic factors, signaling molecules, lipids, DNA, mRNAs, and non-coding RNAs. They are implicated in various physiological and pathological conditions, including ocular surface events, such as corneal scarring, wound healing, and inflammation. Their biocompatibility, stability, low immunogenicity, and easy detectability in bodily fluids (blood, tears, saliva, and urine) make them promising tools for diagnosing and treating ocular diseases. The potential to engineer specific Exo cargos makes them outstanding therapeutic delivery vehicles. The objective of this review is to provide novel insights into the functions of Exo cargos and their applications as biomarkers and therapeutics, or targets in the cornea. Full article

The health burden of ocular toxoplasmosis is substantial, and there is an unmet need for safe and curative anti-microbial drugs. One major barrier to research on new therapeutics is the lack of in vitro human-based models beyond two-dimensional cultured cells and tissue explants. We aimed to address this research gap by establishing a human retinal organoid model of ocular toxoplasmosis. Retinal organoids, generated from human induced pluripotent stem cells and grown to two stages of organization, were incubated with a suspension of live or heat-killed GT-1 strain T. gondii tachyzoites, or medium without tachyzoites. Both developing (1 month post-isolation) and matured (6 months post-isolation) organoids were susceptible to infection. Spread of live parasites from the margin to the entire organoid over 1 week was indicated by immunolabelling for T. gondii surface antigen 1. This progression was accompanied by changes in the levels of selected tachyzoite transcripts—SAG1, GRA6, and ROP16—and human cytokine transcripts—CCL2, CXCL8, CXCL10, and IL6—in infected versus control conditions. Our human retinal organoid model of ocular toxoplasmosis offers the opportunity for many future lines of study, including tachyzoite interactions with retinal cell populations and leukocyte subsets, parasite stage progression, and disease processes of different T. gondii strains, as well as drug testing. Full article