Search

Aim: To investigate the role of interleukin-17 in ocular surface and corneal disease. Ocular surface and corneal disease is a leading cause of blindness and is an ongoing challenge for the public health sector to implement effective therapies. The majority of cells in corneal lesions are derived primarily from neutrophils that induce inflammatory events that lead to tissue damage. One of the key pro-inflammatory cytokines is IL-17, and it has been investigated in order to facilitate the understanding of the pathogenesis of ocular surface lesion development. Method: A review of the literature was performed through a systematic approach. Results: IL-17 has been shown to exacerbate dry eye disease, viral and bacterial keratitis lesion severity, although it was found to be protective for Acanthamoeba. Antibodies developed to neutralize IL-17 have shown some promise in reducing the severity of some diseases. Conclusion: IL-17 plays a role in the pathogenesis of ocular surface and corneal disease and targeting this cytokine may provide a useful treatment option in the future. [ABSTRACT FROM AUTHOR]

Purpose: Contact lens behaviours such as poor hand and lens hygiene are common and are associated with increased risk of microbial keratitis. Evidence for health promotion strategies to address this gap is required. The trial examined the effectiveness of a customised text-messaging intervention on compliance, discontinuation rate and wearer satisfaction in contact lens wearers., Methods: The parallel group, double masked, randomised clinical trial was pre-registered with the Australian and New Zealand Clinical Trials Registry (ACTRN12621001719820). Contact lens wearers were recruited using social media and optometry partners in clinical practice. Participants (n = 76) received the intervention and usual care. The control group (n = 75) received usual care. Intervention text messages (range 56-76) were customised, provided education, reminders, and motivation and were delivered over six months. Outcomes were validated self-report online surveys for compliance (0-100), satisfaction (0-100) and discontinuation (Y/N), at 3 months and 6 months. Secondary outcomes were intervention feasibility and acceptability., Results: Participants mean age was 38 years, 105/151 (70 %) female and 83 % completed the trial (intervention 60/76, control 65/75). The intervention group demonstrated better compliance than control with an adjusted between-group-difference at 3 months of 5.2, 95 % confidence interval (CI), 1.6-8.7, P = 0.004 and at 6 months 3.9, 95 % CI 0.2-7.6, P = 0.04. This difference in compliance is clinically significant, equivalent to a single change in a behaviour such as starting to handwash or ceasing overnight wear. There was no adjusted between-group-difference in satisfaction at 3 months (0.8, 95 % CI -4.3-6.0, P = 0.75) or at 6 months (-0.4, 95 % CI -5.7-4.9, P = 0.89). Few participants (7/151, 4.6 %) discontinued contact lens wear (3 intervention, 4 control). The messages were delivered successfully (98 %), at A$11 per participant. Participants reported appropriate message content (75 %), language (80 %) and delivery timing (97 %)., Conclusion: This customised text message intervention was a feasible and acceptable method for improving contact lens compliance., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: NC was awarded a UNSW Scientia Fellowship and AS was supported by a PhD Scientia Scholarship. This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. All authors attest that they meet the current ICMJE criteria for authorship. Authors AS, KF and LK indicate no financial disclosures or conflicts of interest. NC has previously received an educational grant from Alcon, honoraria from the British Contact lens Association (UK) and Optometry Virtually Connected, and travel grants from Standards Australia, and Australian Vision Convention (QLD/NT)., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

This paper seeks to outline the history, market situation, clinical management and product performance related to the correction of presbyopia with both contact lenses and spectacles. The history of the development of various optical forms of presbyopic correction are reviewed, and an overview is presented of the current market status of contact lenses and spectacles. Clinical considerations in the fitting and aftercare of presbyopic contact lens and spectacle lens wearers are presented, with general recommendations for best practice. Current options for contact lens correction of presbyopia include soft simultaneous, rigid translating and rigid simultaneous designs, in addition to monovision. Spectacle options include single vision lenses, bifocal lenses and a range of progressive addition lenses. The comparative performance of both contact lens and spectacle lens options is presented. With a significant proportion of the global population now being presbyopic, this overview is particularly timely and is designed to act as a guide for researchers, industry and eyecare practitioners alike., Competing Interests: Declaration of competing interest Philip B Morgan has received honoraria from Alcon, Bausch + Lomb, CooperVision, Menicon and Johnson & Johnson and grants/funding from Alcon, Bausch + Lomb, Clearlab, CooperVision, Daysoft, Johnson & Johnson Vision, Mark'Ennovy, Menicon and Visco Vision. Nathan Efron has received honoraria from CooperVision. Eric Papas has had grant funding from CooperVision and Alcon. Nicole Carnt has had funding from Alcon. Manbir Nagra provides consultancy to Menicon and Johnson & Johnson Vision. Helmer Schweizer provides consultancy to Alcon and Bausch + Lomb. Lakshman Subbaraman is an employee and has stock ownership of Alcon. Anna Sulley is an employee of CooperVision. At the time of writing this this paper Andy Hepworth is an employee of EssilorLuxottica. Melissa Barnett, Debarun Dutta, Julie-Anne Little, Heiko Pult, Bridgitte Shen Lee, Alicia Thompson, Alexandra Webster and Maria Markoulli have no declarations of competing interest., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: Microbial keratitis is one of the leading causes of blindness globally. An overactive immune response during an infection can exacerbate damage, causing corneal opacities and vision loss. This study aimed to identify the differentially expressed genes between corneal infection patients and healthy volunteers within the cornea and conjunctiva and elucidate the contributing pathways to these conditions' pathogenesis. Moreover, it compared the corneal and conjunctival transcriptomes in corneal-infected patients to cytokine levels in tears., Methods: Corneal and conjunctival swabs were collected from seven corneal infection patients and three healthy controls under topical anesthesia. RNA from seven corneal infection patients and three healthy volunteers were analyzed by RNA sequencing (RNA-Seq). Tear proteins were extracted from Schirmer strips via acetone precipitation from 38 cases of corneal infection and 14 healthy controls. The cytokines and chemokines IL-1β, IL-6, CXCL8 (IL-8), CX3CL1, IL-10, IL-12 (p70), IL-17A, and IL-23 were measured using an antibody bead assay., Results: A total of 512 genes were found to be differentially expressed in infected corneas compared to healthy corneas, with 508 being upregulated and four downregulated (fold-change (FC) <-2 or > 2 and adjusted p <0.01). For the conjunctiva, 477 were upregulated, and 3 were downregulated (FC <-3 or ≥ 3 and adjusted p <0.01). There was a significant overlap in cornea and conjunctiva gene expression in patients with corneal infections. The genes were predominantly associated with immune response, regulation of angiogenesis, and apoptotic signaling pathways. The most highly upregulated gene was CXCL8 (which codes for IL-8 protein). In patients with corneal infections, the concentration of IL-8 protein in tears was relatively higher in patients compared to healthy controls but did not show statistical significance., Conclusions: During corneal infection, many genes were upregulated, with most of them being associated with immune response, regulation of angiogenesis, and apoptotic signaling. The findings may facilitate the development of treatments for corneal infections that can dampen specific aspects of the immune response to reduce scarring and preserve sight., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Alenezi, Parnell, Schibeci, Ozkan, Willcox, White and Carnt.)

Acanthamoeba , a free-living amoeba in water and soil, is an emerging pathogen causing severe eye infection known as Acanthamoeba keratitis. In its natural environment, Acanthamoeba performs a dual function as an environmental heterotrophic predator and host for a range of microorganisms that resist digestion. Our objective was to characterize the intracellular microorganisms of phylogenetically distinct Acanthamoeba spp. isolated in Australia and India through directly sequencing 16S rRNA amplicons from the amoebae. The presence of intracellular bacteria was further confirmed by in situ hybridization and electron microscopy. Among the 51 isolates assessed, 41% harboured intracellular bacteria which were clustered into four major phyla: Pseudomonadota (previously known as Proteobacteria), Bacteroidota (previously known as Bacteroidetes), Actinomycetota (previously known as Actinobacteria), and Bacillota (previously known as Firmicutes). The linear discriminate analysis effect size analysis identified distinct microbial abundance patterns among the sample types; Pseudomonas species was abundant in Australian corneal isolates ( P  < 0.007), Enterobacteriales showed higher abundance in Indian corneal isolates ( P  < 0.017), and Bacteroidota was abundant in Australian water isolates ( P  < 0.019). The bacterial beta diversity of Acanthamoeba isolates from keratitis patients in India and Australia significantly differed ( P  < 0.05), while alpha diversity did not vary based on the country of origin or source of isolation ( P  > 0.05). More diverse intracellular bacteria were identified in water isolates as compared with clinical isolates. Confocal and electron microscopy confirmed the bacterial cells undergoing binary fission within the amoebal host, indicating the presence of viable bacteria. This study sheds light on the possibility of a sympatric lifestyle within Acanthamoeba , thereby emphasizing its crucial role as a bunker and carrier of potential human pathogens., Competing Interests: The authors have declared that no competing interests exist., (© The Author(s) 2024. Published by Oxford University Press on behalf of the International Society for Microbial Ecology.)

Background: Acanthamoeba is an environmental host for various microorganisms. Acanthamoeba is also becoming an increasingly important pathogen as a cause of keratitis. In Acanthamoeba keratitis (AK), coinfections involving pathogenic bacteria have been reported, potentially attributed to the carriage of microbes by Acanthamoeba. This study assessed the presence of intracellular bacteria in Acanthamoeba species recovered from domestic tap water and corneas of two different AK patients and examined the impact of naturally occurring intracellular bacteria within Acanthamoeba on the severity of corneal infections in rats., Methodology/principal Findings: Household water and corneal swabs were collected from AK patients. Acanthamoeba strains and genotypes were confirmed by sequencing. Acanthamoeba isolates were assessed for the presence of intracellular bacteria using sequencing, fluorescence in situ hybridization (FISH), and electron microscopy. The viability of the bacteria in Acanthamoeba was assessed by labelling with alkyne-functionalized D-alanine (alkDala). Primary human macrophages were used to compare the intracellular survival and replication of the endosymbiotic Pseudomonas aeruginosa and a wild type strain. Eyes of rats were challenged intrastromally with Acanthamoeba containing or devoid of P. aeruginosa and evaluated for the clinical response. Domestic water and corneal swabs were positive for Acanthamoeba. Both strains belonged to genotype T4F. One of the Acanthamoeba isolates harboured P. aeruginosa which was seen throughout the Acanthamoeba's cytoplasm. It was metabolically active and could be seen undergoing binary fission. This motile strain was able to replicate in macrophage to a greater degree than strain PAO1 (p<0.05). Inoculation of Acanthamoeba containing the intracellular P. aeruginosa in rats eyes resulted in a severe keratitis with increased neutrophil response. Acanthamoeba alone induced milder keratitis., Conclusions/significance: Our findings indicate the presence of live intracellular bacteria in Acanthamoeba can increase the severity of acute keratitis in vivo. As P. aeruginosa is a common cause of keratitis, this may indicate the potential for these intracellular bacteria in Acanthamoeba to lead to severe polymicrobial keratitis., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Rayamajhee et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Acanthamoeba is an opportunistic free-living heterotrophic protist that is the most predominant amoeba in diverse ecological habitats. Acanthamoeba causes amoebic keratitis (AK), a painful and potentially blinding corneal infection. Major risk factors for AK have been linked to non-optimal contact lens hygiene practices and Acanthamoeba contamination of domestic and recreational water. This study investigated the incidence and seasonal variation of Acanthamoeba spp. within coastal lagoons located on the eastern coast of Australia and then examined the association between Acanthamoeba and water abiotic factors and bacterial species within the water. Water samples were collected from four intermittently closed and open lagoons (ICOLLs) (Wamberal, Terrigal, Avoca and Cockrone) every month between August 2019 to July 2020 except March and April. qPCR was used to target the Acanthamoeba 18S rRNA gene, validated by Sanger sequencing. Water abiotic factors were measured in situ using a multiprobe metre and 16S rRNA sequencing (V3-V4) was performed to characterise bacterial community composition. Network analysis was used to gauge putative associations between Acanthamoeba incidence and bacterial amplicon sequence variants (ASVs). Among 206 water samples analysed, 79 (38.3%) were Acanthamoeba positive and Acanthamoeba level was significantly higher in summer compared with winter, spring, or autumn (p = 0.008). More than 50% (23/45) water samples of Terrigal were positive for Acanthamoeba which is a highly urbanised area with extensive recreational activities while about 32% (16/49) samples were positive from Cockrone that is the least impacted lagoon by urban development. All sequenced strains belonged to the pathogenic genotype T4 clade except two which were of genotype clades T2 and T5. Water turbidity, temperature, intl1 gene concentration, and dissolved O 2 were significantly associated with Acanthamoeba incidence (p < 0.05). The ASVs level of cyanobacteria, Pseudomonas spp., Candidatus spp., and marine bacteria of the Actinobacteria phylum and Acanthamoeba 18S rRNA genes were positively correlated (Pearson's r ≥ 0.14). The presence of Acanthamoeba spp. in all lagoons, except Wamberal, was associated with significant differences in the composition of bacterial communities (beta diversity). The results of this study suggest that coastal lagoons, particularly those in urbanised regions with extensive water recreational activities, may pose an elevated risk to human health due to the relatively high incidence of pathogenic Acanthamoeba in the summer. These findings underscore the importance of educating the public about the rare yet devastating impact of AK on vision and quality of life, highlighting the need for collaborative efforts between public health officials and educators to promote awareness and preventive measures, especially focusing lagoons residents and travellers., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

The healthy human cornea is a uniquely transparent sensory tissue where immune responses are tightly controlled to preserve vision. The cornea contains immune cells that are widely presumed to be intraepithelial dendritic cells (DCs). Corneal immune cells have diverse cellular morphologies and morphological alterations are used as a marker of inflammation and injury. Based on our imaging of corneal T cells in mice, we hypothesized that many human corneal immune cells commonly defined as DCs are intraepithelial lymphocytes (IELs). To investigate this, we developed functional in vivo confocal microscopy (Fun-IVCM) to investigate cell dynamics in the human corneal epithelium and stroma. We show that many immune cells resident in the healthy human cornea are T cells. These corneal IELs are characterized by rapid, persistent motility and interact with corneal DCs and sensory nerves. Imaging deeper into the corneal stroma, we show that crawling macrophages and rare motile T cells patrol the tissue. Furthermore, we identify altered immune cell behaviors in response to short-term contact lens wear (acute inflammatory stimulus), as well as in individuals with allergy (chronic inflammatory stimulus) that was modulated by therapeutic intervention. These findings redefine current understanding of immune cell subsets in the human cornea and reveal how resident corneal immune cells respond and adapt to chronic and acute stimuli.

Objective: The study aimed to profile and quantify tear metabolites associated with bacterial keratitis using both untargeted and targeted metabolomic platforms., Methods: Untargeted metabolomic analysis using liquid-chromatography-Q Exactive-HF mass-spectrometry explored tear metabolites significantly associated with bacterial keratitis (n = 6) compared to healthy participants (n = 6). Differential statistics and principal component analysis determined meaningful metabolite differences between cases and controls. Purines and nucleosides were further quantified and compared between 15 cases and 15 controls in the targeted metabolomic platform using TSQ quantum access triple quadrupole mass spectrometry. Compound quantification was done by plotting the calibration curves and the difference in the compound levels was evaluated using the Wilcoxon rank-sum test., Results: In the untargeted analysis, 49 tear metabolites (27 upregulated and 22 downregulated) were differentially expressed between cases and controls. The untargeted analysis indicated that the purine metabolism pathway was the most affected by bacterial keratitis. Metabolite quantification in the targeted analysis further confirmed the upregulation of xanthine (P = 0.02) and downregulation of adenine (P < 0.0001), adenosine (P < 0.0001) and cytidine (P < 0.0001) in the tears of participants with bacterial keratitis compared to that of healthy participants., Conclusions: Bacterial keratitis significantly changes the tear metabolite profile, including five major compound classes such as indoles, amino acids, nucleosides, carbohydrates, and steroids. This study also indicates that tear fluids can be used to map the metabolic pathways and uncover metabolic markers associated with bacterial keratitis. Conceivably, the inhibition of nucleoside synthesis may contribute to the pathophysiology of bacterial keratitis because nucleosides are required for maintaining cellular energy homeostasis and immune adaptability., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Purpose: This study was designed to establish risk factors for the development of Acanthamoeba keratitis (AK) for daily disposable (DD) contact lens (CL) users compared with daily wear (DW) reusable lens users and for risks unique to DD users. This is important because, in many major economies, CL use is the principal cause of microbial keratitis, of which AK accounts for approximately 50% of cases with sight loss. Determining these AK risks informs practitioner advice and consumer behavior., Design: Case-control study., Participants: Cases and controls were recruited from an Accident and Emergency Department serving South-East England. Cases were new CL users with AK recruited retrospectively from January 2011 to February 2013 and prospectively thereafter until August 2014. Controls were recruited prospectively from February 2014 to June 2015., Methods: Analysis of a self-administered questionnaire., Main Outcome Measures: Independent risk factors and population attributable risk percentage (PAR%) for AK., Results: A total of 83 AK cases and 122 controls were recruited; DD use was reported by 20 (24%) cases and 66 (54%) controls. In multivariable analyses adjusted for potential confounders, the odds of AK was higher for DW reusable soft lenses (odds ratio [OR], 3.84; 95% confidence interval [CI], 1.75-8.43) and rigid lenses (OR, 4.56; 95% CI, 1.03-20.19) than for DD lenses. Within the DD-using subset, AK was associated with the following modifiable risk factors: less frequent professional follow-up visits (OR, 10.12; 95% CI, 5.01-20.46); showering in lenses (OR, 3.29, 95% CI, 1.17-9.23); lens reuse (OR, 5.41; 95% CI, 1.55-18.89); and overnight wear (OR, 3.93; 95% CI, 1.15-13.46). The PAR% estimated that 30% to 62% of cases could be prevented by switching from reusable soft lens to DD lens use., Conclusions: Acanthamoeba keratitis risks are increased > threefold in DW reusable lens users versus DD lens use. Acanthamoeba keratitis risks for DD lens users can be minimized by adherence to safe use guidelines (no reuse, overnight wear, or contamination by water). Safe CL use can be improved by increasing the prominence of risk avoidance information from manufacturers and regulators. Because AK accounts for half of severe keratitis in CL users, these measures can be expected to have public health benefits., (Copyright © 2022 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Aims: To evaluate the sensitivity and specificity of polymerase chain reaction (PCR), in vivo confocal microscopy (IVCM) and culture for microbial keratitis (MK) diagnosis., Methods: Retrospective review of PCR, IVCM and culture results for MK diagnosis at Moorfields Eye Hospital between August 2013 and December 2014., Results: PCR results were available for 259 MK patients with concurrent culture for 203/259 and IVCM for 149/259. Sensitivities and specificities with 95% confidence intervals [95% CI] were calculated for Acanthamoeba keratitis (AK) and fungal keratitis (FK), by comparison with culture, for both IVCM and PCR. For AK, FK and bacterial keratitis (BK) sensitivities were calculated, for each diagnostic method, by comparison with a composite reference standard (a positive result for one or more of culture, PCR or IVCM having a specificity of 100% by definition). For the latter, sensitivities with [95% CI] were: for AK, IVCM 77.1% [62.7-88.0%], PCR 63.3% [48.3-76.6%], culture 35.6 [21.9-51.2]; for FK, IVCM 81.8% [48.2-97.7%], PCR 30.8% [9.09-61.4%], culture 41.7% [15.2-72.3%]; for BK, PCR 25.0% [14.7-37.9%], culture 95.6% [87.6-99.1%]., Conclusion: IVCM was the most sensitive technique for AK and FK diagnosis but culture remains our gold standard for BK. These findings reflect results to be expected from service providers to UK ophthalmology units and demonstrates the need at our centre for ongoing diagnostic result audit leading to the potential to improve PCR diagnosis. Both FK and AK are now common in the UK; ophthalmology units need to have all these techniques available to optimise their MK management., (© 2021. The Author(s).)

The opportunistic protist Acanthamoeba, which interacts with other microbes such as bacteria, fungi, and viruses, shows significant similarity in cellular and functional aspects to human macrophages. Intracellular survival of microbes in this microbivorous amoebal host may be a crucial step for initiation of infection in higher eukaryotic cells. Therefore, Acanthamoeba-microbe adaptations are considered an evolutionary model of macrophage-pathogen interactions. This paper reviews Acanthamoeba as an emerging human pathogen and different ecological interactions between Acanthamoeba and microbes that may serve as environmental training grounds and a genetic melting pot for the evolution, persistence, and transmission of potential human pathogens., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Introduction: Acanthamoeba is an emerging pathogen, infamous for its resilience against antiprotozoal compounds, disinfectants and harsh environments. It is known to cause keratitis, a sight-threatening, painful and difficult to treat corneal infection which is often reported among contact lens wearers and patients with ocular trauma. Acanthamoeba comprises over 24 species and currently 23 genotypes (T1-T23) have been identified., Aims: This retrospective study was designed to examine the Acanthamoeba species and genotypes recovered from patients with Acanthamoeba keratitis (AK), determine the presence of endosymbionts in ocular isolates of Acanthamoeba and review the clinical presentations., Methodology: Thirteen culture-confirmed AK patients treated in a tertiary eye care facility in Hyderabad, India from February to October 2020 were included in this study. The clinical manifestations, medications and visual outcomes of all patients were obtained from medical records. The Acanthamoeba isolates were identified by sequencing the ribosomal nuclear subunit (rns) gene. Acanthamoeba isolates were assessed for the presence of bacterial or fungal endosymbionts using molecular assays, PCR and fluorescence in situ hybridization (FISH)., Results: The mean age of the patients was 33 years (SD ± 17.4; 95% CI 22.5 to 43.5 years). Six (46.2%) cases had AK associated risk factors; four patients had ocular trauma and two were contact lens wearers. A. culbertsoni (6/13, 46.2%) was the most common species, followed by A. polyphaga and A. triangularis. Most of the isolates (12/13) belonged to genotype T4 and one was a T12; three sub-clusters T4A, T4B, and T4F were identified within the T4 genotype. There was no significant association between Acanthamoeba types and clinical outcomes. Eight (61.5%) isolates harboured intracellular bacteria and one contained Malassezia restricta. The presence of intracellular microbes was associated with a higher proportion of stromal infiltrates (88.9%, 8/9), epithelial defect (55.6%, 5/9) and hypopyon (55.6%, 5/9) compared to 50% (2/4), 25% (1/4) and 25% (1/4) AK cases without intracellular microbes, respectively., Conclusions: Genotype T4 was the predominant isolate in southern India. This is the second report of T12 genotype identified from AK patient in India, which is rarely reported worldwide. The majority of the Acanthamoeba clinical isolates in this study harboured intracellular microbes, which may impact clinical characteristics of AK., (© 2022. The Author(s).)

Purpose: To determine if there is diurnal variation in gene expression in normal healthy conjunctival cells., Methods: Bulbar conjunctival swab samples were collected from four healthy subjects in the morning and evening of the same day. The two swab samples were taken from one eye of each participant, with a minimum of five hours gap between the two samples. RNA was extracted and analysed using RNA sequencing (RNA-Seq)., Results: A total of 121 genes were differentially expressed between the morning and the evening conjunctival samples, of which 94 genes were upregulated in the morning, and 27 genes were upregulated in the evening. Many of the genes that were upregulated in the morning were involved in defence, cell turnover and regulation of gene expression, while the genes upregulated in the evening were involved in signalling and mucin production., Conclusions: This study has identified several genes whose expression changes over the course of the day. Knowledge of diurnal variations of conjunctival gene expression provides an insight into the regulatory status of the healthy eye and provides a baseline for examining changes during ocular surface disease., (Copyright © 2021 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.)

Glaucoma is a chronic optic neuropathy that creates a significant burden on public health. Oxidative stress is hypothesized to play a role to glaucoma progression, and its reduction is being analyzed as a therapeutic target. Dietary antioxidants play a crucial role in helping provide insight into this hypothesis. We reviewed 71 trials, interventional, in-vivo and Iin vitro, including 11 randomized controlled trials, to determine if adjunctive nutritional supplementation could lead to a reduction in oxidative stress and prevent glaucomatous progression. Many laboratory findings show that vitamins and natural compounds contain an abundance of intrinsic antioxidative, neuroprotective and vasoprotective properties that show promise in the treatment and prevention of glaucoma. Although there is encouraging early evidence, most clinical findings are inconclusive. The group of B vitamins appear to have the greatest amount of evidence. Other compounds such as flavonoids, carotenoids, curcumin, saffron, CoQ10, gingko biloba, and resveratrol however warrant further investigation in glaucoma patients. Studies of these antioxidants and other nutrients could create adjunctive or alternative preventative and treatment modalities for glaucoma to those currently available., Competing Interests: Declaration of Competing Interest The authors of this paper have no conflicts of interest to declare., (Crown Copyright © 2021. Published by Elsevier Inc. All rights reserved.)

Acanthamoeba keratitis (AK) is a rare but severe eye disease. A research engagement event, "The Cornea Day," in London, UK in 2013, identified the lack of credible information about AK and a need for practical day to day management strategies. Experiences of 15 AK patients attending The Cornea Day were distilled into a survey that was administered to a wider group of 76 patients, carers, researchers, and clinicians. A Patient Information Leaflet was cocreated and then represented to additional patients for final modification. The AK Patient Leaflet (revised 2019) is available in several languages and used globally., Competing Interests: Declaration of Conflicting Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2022.)

Mucosal linings of the body, including the conjunctiva, are enriched in tissue-resident memory T cells (T RMs ) whose defining feature is their continual tissue protection that does not rely on migration to lymphoid organs to elicit immune responses. Hitherto, conjunctival T RMs have only been identified in the superficial epithelium. This work aims to develop a more complete understanding of the conjunctival immunological capacity by investigating the presence of T RMs within the deeper, more stable layers of the healthy human conjunctiva. Using immunofluorescence microscopy and antibodies against CD3, CD4, CD69 and HLA-DR on bulbar conjunctival biopsies obtained from 7 healthy adults (age range = 32-77 years; females = 4), we identified CD69 + T RM subsets in all layers of the human conjunctiva: the superficial epithelium, the basal epithelium, the adenoid, and the fibrous layers. Interestingly, the adenoid layer showed significantly higher densities of both CD4 and CD8 T RMs when compared to the fibrous layer and conjunctival epithelia. Additionally, CD4 T RMs predominated significantly over CD8 T RMs in the adenoid layer. The abundance of deep conjunctival CD69 + T RMs within the healthy human may suggest the presence of defence mechanisms capable of inducing long-term immunogenic memory. Understanding this spatial distribution of conjunctival CD69 + T RMs is essential to improving mucosal vaccine design., (© 2022. The Author(s).)

Abstract: Infectious keratitis is a rare but severe condition associated with a range of ocular and systemic predisposing conditions, including ocular trauma, prior surgery, surface disease, and contact lens (CL) wear. This review explores the epidemiology of infectious keratitis, specifically the differences in disease incidence and risk factors, causative organism profile and virulence characteristics and host microbiome, genetics, gene expression, proteomics, and metabolomic characteristics in CL-related and non-CL-related diseases. Differences exist in the epidemiology, demographics, causative organisms, and their virulence characteristics in CL-related and non-CL-related diseases, and there is less evidence to support differences between these groups of individuals in the ocular surface microbiome, genetics, and pathways of disease. Genetic variations, however, in the host immune profile are implicated in both the onset and severity of infectious keratitis in CL and non-CL wearers. As technologies in metabolomics, proteomics, and genomics improved to be better able to process small-volume samples from the ocular surface, there will be improved understanding of the interplay between the CL, ocular surface, host immune profile, and the microbial environment. This may result in a more personalized approach in the management of disease to reduce disease severity., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2022 Contact Lens Association of Ophthalmologists.)

The COVID-19 pandemic has resulted in an unprecedented impact on global health, economy, and way of life. SARS-CoV-2, the virus responsible for the disease, utilizes the ACE2 receptor found on host cells to mediate entry, replication, and infection. Numerous studies have elucidated the presence of many components of the renin-angiotensin-aldosterone system (RAAS) in the eye, including the ACE2 receptor. Considering this, and the anatomical vulnerability that the exposed ocular surface offers with its interconnectedness to the respiratory system, there is a theoretical risk of pathogen entry from the ocular route as well as the development of COVID-19-associated eye disease. Despite this, the actual epidemiological data demonstrates low ocular symptoms, possibly due to differing ACE2 receptor expression across age, ethnicity, and sex coupled with the protective properties of tears. We summarize the current literature on ocular RAAS with specific focus on the ACE2 receptor and its interplay with the SARS-CoV-2 virus., Competing Interests: The authors declare that there are no conflicts of interest regarding the publication of this article., (Copyright © 2022 Ali Abid et al.)

Purpose: To investigate the effect of long-term extended soft contact lens wear on limbal and central corneal cell morphology, and limbal architecture., Methods: Each participant attended a study visit involving in vivo confocal microscopy of central corneal and limbal epithelium. Scans were graded by five masked graders for three features: central epithelial irregularity, limbal epithelial irregularity and the prominence of palisades of Vogt. The variability of grades between different graders and the difference of grades between extended wearers and daily soft/non-contact lens wearers were assessed., Results: Nineteen participants (9 extended soft contact lens wearers and 10 daily soft/non-contact lens wearers) aged 31-65 years were enrolled in this study. Scans from 37 eyes were included in the analysis. Agreement between graders for each feature was moderate to good with inter class correlation >0.7. While there were no significant differences in central epithelial cell irregularity (p = 0.527) and the prominence of palisade of Vogt (p = 0.182) between extended or daily soft/non-contact lens wearers, limbal epithelial cell irregularity showed a trend with increased irregularity in extended soft contact lens wearers (p = 0.091)., Conclusions: While no differences in limbal cell morphology and structureor central epithelial cell wasfound in thissubjective grading study of extended wearers compared to daily soft/non-contact lens wearers, further studies using a larger sample size or a longitudinal study design are warranted., (Crown Copyright © 2021. Published by Elsevier Ltd. All rights reserved.)

Purpose: This study aims to review the literature that compares the accuracy of Anterior Segment-Optical Coherence Tomography (AS-OCT) against gonioscopy in detecting eyes with angle closure. It is currently unclear how AS-OCT fits into clinical practice for detecting angle closure. This is a systematic review and meta-analysis., Methods: A literature search was performed on Medline, Embase, Scopus and the Cochrane Central Register of Controlled Trials to identify studies that investigated the diagnostic accuracy of AS-OCT in detecting eyes with angle closure as diagnosed by gonioscopy. Eligible studies included in the analysis met stringent inclusion criteria determining the sensitivity and specificity of AS-OCT., Results: The initial search identified 727 studies, of which 23 were included in the final analysis. We found substantial variation in the parameters being studied and methodologies. The sensitivity of AS-OCT ranged from 46 to 100% (median 87%). Twenty-one studies identified parameters that showed sensitivity above 80%. The specificity ranged from 55.3 to 100% (median 84%)., Conclusion: AS-OCT demonstrates good sensitivity for detecting angle closure. It may provide an avenue to address high rates of undiagnosed angle closure, such as found in developing Asian countries. However, AS-OCT is not yet able to replace gonioscopy. Clinicians should consider whether the diagnostic accuracy of AS-OCT is acceptable for their specific clinical use before adopting it. More studies are needed to determine the utility of AS-OCT, including longitudinal studies to determine the significance of eyes classified to have closed angles by AS-OCT but open on gonioscopy., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Significance: Water exposure during contact lens wear can transfer pathogenic microorganisms to the eye, causing ocular complications. This study determined that water exposure is prevalent among lens wearers and is independently associated with higher case contamination. Contact lens compliance education to minimize water exposure should be reenforced by contact lens organizations and practitioners., Purpose: Given the increasing association between water exposure and contact lens disease, this study aimed to explore the effect of water exposure and storage case contamination in soft contact lens users., Methods: A total of 165 daily soft lens wearers completed a self-administered questionnaire on contact lens hygiene. Lens cases were collected, and microbial analysis was conducted using an adenosine triphosphate assay (for overall microbial bioburden) and limulus amebocyte lysate assay (for endotoxin levels). The lens hygiene (excellent, >35; moderate, 28 to 35; poor, <28) and water contact (≤1, good; >1, poor) scores measured the compliance and water exposure during lens wear, respectively. Multiple regression determined the association between water behaviors and case contamination., Results: The average (standard deviation) age of participants was 28 (13.5) years (18 to 78 years), and 65% were female. The average overall microbial bioburden of storage cases was 3.10 (0.98) log colony-forming unit/mL (1.09 to 5.94 log colony-forming unit/mL). Forty-five percent of participants reported showering, 49.7% reported swimming while wearing lenses (65.4% of whom swam without goggles), 27.8% used wet hands to handle lenses, and 17.5% used tap water to rinse storage cases. Showering with lenses significantly increased the risk of higher storage case bioburden (P = .001), whereas using wet hands (P = .01) doubled the risk of higher case endotoxin levels (odds ratio, 2.41; confidence interval 1.19 to 4.86)., Conclusions: Water contact behavior while wearing lenses is prevalent among soft lens wearers and is associated with higher case contamination. Practitioners may improve contact lens education to reduce water exposure and case contamination to reduce the risk of lens-related adverse events., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest., (Copyright © 2021 American Academy of Optometry.)

Competing Interests: We declare no competing interests.

Currently, intraocular pressure is the only modifiable risk factor for glaucoma; thus, identifying other modifiable determinants may have far-reaching outcomes. There has been increasing interest in vitamin D status and glaucoma pathogenesis as low vitamin D has been identified by some studies as an independent risk factor for glaucoma. Although the exact mechanism of vitamin D in glaucoma remains uncertain, there is sufficient evidence to continue research in this area. There is a potential physiological role for vitamin D as an anti-inflammatory agent in the oxidative stress-driven pathogenesis of primary open-angle glaucoma, and further studies are required to evaluate the temporal and causal relationship. Ocular vitamin D status in the tear, aqueous and vitreous fluid is a prospective gap in research., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Contact lens-related complications are common, affecting around one third of wearers, although most are mild and easily managed. Contact lenses have well-defined anatomical and physiological effects on the ocular surface and can result in other consequences due to the presence of a biologically active material. A contact lens interacts with the tear film, ocular surface, skin, endogenous and environmental microorganisms, components of care solutions and other antigens which may result in disease specific to contact lens wear, such as metabolic or hypersensitivity disorders. Contact lens wear may also modify the epidemiology or pathophysiology of recognised conditions, such as papillary conjunctivitis or microbial keratitis. Wearers may also present with intercurrent disease, meaning concomitant or pre-existing conditions unrelated to contact lens wear, such as allergic eye disease or blepharitis, which may complicate the diagnosis and management of contact lens-related disease. Complications can be grouped into corneal infection (microbial keratitis), corneal inflammation (sterile keratitis), metabolic conditions (epithelial: microcysts, vacuoles, bullae, tight lens syndrome, epithelial oedema; stromal: superficial and deep neovascularisation, stromal oedema [striae/folds], endothelial: blebs, polymegethism/ pleomorphism), mechanical (corneal abrasion, corneal erosion, lens binding, warpage/refractive error changes; superior epithelial arcuate lesion, mucin balls, conjunctival epithelial flaps, ptosis, discomfort), toxic and allergic disorders (papillary conjunctivitis, solution-induced corneal staining, incomplete neutralisation of peroxide, Limbal Stem Cell Deficiency), tear resurfacing disorders/dry eye (contact lens-induced dry eye, Meibomian gland dysfunction, lid wiper epitheliopathy, lid parallel conjunctival folds, inferior closure stain, 3 and 9 o'clock stain, dellen, dimple veil) or contact lens discomfort. This report summarises the best available evidence for the classification, epidemiology, pathophysiology, management and prevention of contact lens-related complications in addition to presenting strategies for optimising contact lens wear., (Copyright © 2021 British Contact Lens Association. All rights reserved.)

Optometry Australia's infection control guidelines 2020 deliver a revision of the paper: Infection control guidelines for optometrists 2016. A review of recent literature was undertaken, with information collected from peer-reviewed journal articles, guidelines from professional societies, government health departments and instructions from equipment manufacturers. This information was used to provide an update on current infection control best practice. The guidelines are presented in two sections: standard precautions and transmission-based precautions. The standard (routine) precautions section covers: hand hygiene; personal protective equipment; safe handling and disposal of sharps; routine environmental cleaning; reprocessing of reusable equipment, instruments and contact lenses; respiratory hygiene and cough etiquette; aseptic and clean technique; and waste management. The transmission-based precautions section covers considerations for optometry staff and/or patients when standard precautions alone may not be sufficient to prevent the spread of an infectious agent; particularly relevant during the COVID-19 pandemic. Finally, a comprehensive list of disinfection or sterilisation techniques to use on reusable devices, instruments or equipment in optometric practice is provided in an Appendix.

Background: Water exposure during contact lens wear has been associated with contact lens disease including microbial keratitis and sterile corneal infiltrates. Despite the documented risks, water exposure is common amongst lens wearers. This study aimed to determine the effect of water education in the form of "no-water" lens case stickers on water-contact behaviours and storage case contamination., Methods: In a prospective, masked, randomised controlled trial, 200 daily lens wearers were randomised to either receive a storage case with a "no-water" sticker (test) or without a "no-water" sticker (control). Both groups received written compliance information. Participants completed a self-administered lens hygiene questionnaire at baseline and after 6 weeks. Microbial analysis of used storage cases, collected at both study visits, was conducted using ATP and limulus amebocyte lysate (LAL) assays for overall microbial contamination and endotoxin levels, respectively. A one-way ANCOVA and multiple logistic regression determined the change in water-contact behaviours and storage case contamination over time., Results: A total of 188 lens wearers completed both study visits; 128 females and 60 males; average age 29 ± 13 (range 18-78 years); 95 test and 93 control participants. After 6 weeks, the overall water exposure score and endotoxin levels reduced significantly in the test group compared with the control group (p < 0.05). There were no significant changes in individual water-contact behaviours or overall storage case contamination., Conclusion: A no-water infographic on the contact lens case improved overall water-contact behaviours and reduced storage case endotoxin. Refining the messaging may be beneficial in future to improve other aspects of compliance.

Acanthamoeba , an opportunistic pathogen is known to cause an infection of the cornea, central nervous system, and skin. Acanthamoeba feeds different microorganisms, including potentially pathogenic prokaryotes; some of microbes have developed ways of surviving intracellularly and this may mean that Acanthamoeba acts as incubator of important pathogens. A systematic review of the literature was performed in order to capture a comprehensive picture of the variety of microbial species identified within Acanthamoeba following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Forty-three studies met the inclusion criteria, 26 studies (60.5%) examined environmental samples, eight (18.6%) studies examined clinical specimens, and another nine (20.9%) studies analysed both types of samples. Polymerase chain reaction (PCR) followed by gene sequencing was the most common technique used to identify the intracellular microorganisms. Important pathogenic bacteria, such as E. coli , Mycobacterium spp. and P. aeruginosa, were observed in clinical isolates of Acanthamoeba , whereas Legionella , adenovirus, mimivirus, and unidentified bacteria ( Candidatus ) were often identified in environmental Acanthamoeba . Increasing resistance of Acanthamoeba associated intracellular pathogens to antimicrobials is an increased risk to public health. Molecular-based future studies are needed in order to assess the microbiome residing in Acanthamoeba , as a research on the hypotheses that intracellular microbes can affect the pathogenicity of Acanthamoeba infections.

Pseudomonas aeruginosa and Staphylococcus aureus are the two dominant Gram-negative and -positive species, respectively, isolated from patients with contact lens-related bacterial keratitis. The clinical features of bacterial keratitis vary, such that timely differential diagnosis can be challenging, which may cause a delay in diagnosis resulting in poorer outcome. This review aims to explore the current understanding of clinical and immunological features associated with contact lens-related P. aeruginosa and S. aureus keratitis based on currently available evidence. Firstly, the review characterises contact lens-related P. aeruginosa and S. aureus keratitis, based on clinical features and prognostic factors. Secondly, the review describes the primary immune response associated with a bacterial infection in in-vivo non-scratch contact lens-wearing animal models, colonised by bacteria on contact lens and topical administration of bacteria on the cornea. Finally, the review discusses the role of macrophage inflammatory protein-2 (MIP-2) and intercellular adhesion molecule (ICAM-1) in neutrophil recruitment based on both in-vivo scratch models of bacterial keratitis and bacterial challenged in cell culture models., (Copyright © 2020 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.)

Purpose: To compare the risk of vision loss following contemporary laser-assisted in situ keratomileusis (LASIK) with different types and modality of use of contact lenses., Methods: Data from a previously published study were used to derive the incidence of vision loss (≥ 2 line loss of best corrected spectacle acuity) following microbial keratitis for different contact lens types and wearing modality, stratified by duration of lens wear. A literature search on vision loss following LASIK was performed between 2003 and 2019. The prevalence of vision loss at six months post-surgery was captured from clinical trials published after 2003. A proportion meta-analysis was applied to derive the prevalence of vision loss following LASIK. A least-squares fitting of cumulative vision loss (P, /10 000 wearers) over time (t, years) using an exponential model estimated the years of contact lens wear to which the risk of vision loss with LASIK was equivalent., Results: Vision loss following LASIK occurred in 66 (95% confidence interval [CI] 34-108) per 10 000 wearers. As a conservative estimate based on the lower confidence interval of the estimated equivalent years of contact lens wear, daily wear contact lenses and extended overnight silicone wear hydrogel contact lens need to be worn for 103 (95% [CI] 103-391) and 25 (95% [CI] 25-79) years respectively, to equal the rate of vision loss equivalent to a one-off LASIK procedure., Conclusions: The risk of vision loss to the individual is low with either contact lens wear or refractive surgery. Contact lens wear does not pose a higher risk of vision loss than LASIK surgery for the most common wear modalities., (© 2020 The Authors Ophthalmic & Physiological Optics © 2019 The College of Optometrists.)

Aims: To estimate the incidence of culture-positive microbial keratitis in Queensland and analyse trends in the organisms and their sensitivities cultured from corneal scrapes, especially low-incidence organisms., Methods: Retrospective multicentre case series of all positive corneal scrapes in Queensland, Australia between 2005 and 2015. Pathology organisations in Queensland were identified by online and local directory search and agreed to participate. Digital records of scrapes provided patient demographics and culture and susceptibility results. Trends in the incidence, organisms and sensitivities were monitored with linear regression. The yearly incidence of microbial keratitis was estimated from the Queensland population., Results: The included corneal scrapes totalled 3182, while 1006 were excluded. The included scrapes yielded 4111 organisms. Pseudomonas aeruginosa was the most common single isolate (729, 17.7%), although Gram-positive organisms were more common overall (2737, 66.6%). Fungal organisms were cultured in 6% of cases, while Acanthamoeba comprised only 1% of records. Bacterial organisms were sensitive to all recorded antibiotics in 89% of all isolates and none of the reported antibiotics showed a decreasing trend in susceptibility. The incidence of protozoal isolation decreased over time (p=0.055). Cultures positive for yeasts showed a linear increase in incidence (p=0.045) while moulds showed a spike in incidence in 2010-2012 (p=0.0008)., Conclusion: The estimated incidence of microbial keratitis was 0.66 cases per 10 000 people, the rate of antibiotic susceptibility is high and stable, the incidence of keratitis secondary to protozoa is likely to be decreasing while the incidence of keratitis culturing yeast is increasing., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To describe the association of water exposure with contact lens (CL)-related disease and explore the guidelines regarding water exposure to CL wearers, provided by CL manufacturing industry, global public health, and CL-related professional associations., Methods: A review of the literature was conducted by searching PubMed, MEDLINE, and Web of Science databases up to September 2017 for articles published or translated in English using keywords: contact lens* AND tap water OR swimming OR showering OR water exposure AND microbial keratitis OR Acanthamoeba keratitis OR corneal infiltrate* OR ocular adverse event*. References in all relevant publications were also reviewed., Results: Water exposure during CL wear is associated with complications ranging from sterile corneal infiltrative events to sight-threatening infections. Despite the documented risks due to water exposure, water-related habits are common among CL wearers. This suggests a lack of awareness and understanding regarding the risks among CL wearers and potentially CL practitioners. Discrepancies exist in guidelines for CL hygiene and compliance provided by the CL manufacturing industry, global public health, and CL-related professional associations. There is also widespread use of water imagery within CL marketing and packaging materials. These factors may give rise to confusion among wearers and may contribute toward risk-taking behaviors., Conclusions: Consensus among stakeholders about water and CL care is needed. Guidelines should unequivocally advocate for the avoidance of any water exposure including handling CLs with wet hands, rinsing CLs or storage cases in tap water, showering while wearing CLs and swimming with CLs without wearing goggles.