Analysis of Deposition and Diffusion of Cholesterol in Silicone Hydrogel Contact Lenses Using Confocal Microscopy.

In this study, we investigated lipid deposition and diffusion in silicone hydrogel (Si-Hy) contact lenses using confocal microscopy. Different Si-Hy lenses were analyzed to understand the interaction patterns of cholesterol with various lens materials. The results highlight significant differences in the deposition and diffusion of lipids through the lenses, revealing that some materials, such as comfilcon A, allow lipids to diffuse more freely compared to others, such as samfilcon A, which provides a greater barrier. The study also observed different morphology and movement of lipid agglomerates across the lenses and above it surfaces. These findings contribute to the understanding of lipid-lens interaction, which is important for the development of lenses with improved comfort and functionality. The research highlights the importance of considering lipid interactions in the design and selection of Si-Hy contact lenses to enhance wearer comfort and lens performance.

Impact of wearing dual-focus soft contact lenses on myopia progression: a one-year randomized clinical trial in Chinese school-age children.

BACKGROUND: Myopia is prevalent in China; however, trials involving Chinese children wearing dual-focus soft contact lenses (DFSCL) are limited. Thus, the purpose of this study is to investigate the efficacy of DFSCL among Chinese school-age children. METHODS: Sixty-four children aged 8-12 years with spherical equivalent refraction (SER) between - 0.75D and - 4.00D were recruited in this randomized controlled clinical study. The control group (32 subjects) wore single-vision spectacles (SVS), while the DFSCL group (32 subjects) wore daily disposable + 2.00 D defocus MiSight DFSCL. Follow-up examinations were performed every 3 months to compare the axial length (AL) growth and SER change between the groups for a period of 12 months by using the independent samples t-test or the Mann-Whitney U test. Statistical differences with a P < 0.05, when compared to the control group, are considered indicative of an effective intervention. Multivariate analysis and regression analysis were used to eliminate the effects of confounding factors on the results. RESULTS: A total of 58 subjects, with 30 in the SVS group and 28 in the DFSCL group, completed the follow-up. After adjusting for baseline age, gender, AL and SER, AL growth was 0.33 ± 0.02 mm in the SVS group and 0.23 ± 0.03 mm in the DFSCL group (P = 0.004). SER change was - 0.53 ± 0.06 in the SVS group and - 0.44 ± 0.06 in the DFSCL group (P = 0.308). In the DFSCL group, AL and SER increased 0.11 mm and 0.09 D less than in the SVS group, respectively. Moreover, initial wear of DFSCL may cause occasional blurriness in near vision, and prolonged wear may lead to increased ocular discomfort symptoms such as dryness, itchiness, and foreign body sensation. CONCLUSION: MiSight DFSCL showed a reduction in AL growth during the first three months of wear. However, no significant benefits were observed during the subsequent nine months. No significant differences in the changes of SER were found. TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR2200064731. Registered 15 October 2022, http://www.chictr.org.cn/.

Subjective impressions with myopia control contact lenses versus single vision lenses: A systematic review and meta-analysis.

PURPOSE: To gain insight into patients' visual experiences and satisfaction when using different forms of myopia control lenses. METHODS: PubMed, Cochrane Library, Embase, Scopus and Web of Science databases were searched for articles assessing subjective visual quality with myopia control lenses compared with single-vision lenses (SVLs) up to July 10, 2023. Eight-hundred-and-three articles were retrieved, reviewed and any questionnaire items on subjective impressions of lens wear were meta-analysed. Subgroup analyses were based on the magnitude of defocus (add power) of multifocal soft contact lenses (MFSCLs) and age groups. A random-effects model was employed for meta-analysis, and I2 statistic used to assess the statistical heterogeneity. RESULTS: Nineteen articles fit the criteria, but only six articles involving MFSCLs had relevant data. MFSCLs were associated with lower subjective ratings of vision at different distances compared to SVLs (p < 0.001), but the differences were less than one unit. MFSCLs also yielded lower ratings when moving or walking and/or climbing stairs at -0.38 (-0.69 to -0.07, p = 0.02; I2 = 85 %, p < 0.001) and for subjective comfort (difference of -0.23, -0.41 to -0.05, p = 0.01; I2 = 63 %, p < 0.001). Subjective ratings for playing sports were not different between groups. Experience with MFSCLs was rated lower by young adults compared to children for all variables. In both children and young adults, ratings were lower with higher add compared to lower add MFSCLs. CONCLUSION: Although subjective ratings for vision and comfort were lower with MFSCLs compared to SVLs, the difference was mostly less than one unit. Importantly, young adults rated their visual experience lower compared to children.

Elucidating acceptance and clinical indications to support the rational design of drug-eluting contact lenses.

The advent of drug-eluting contact lenses (DECLs) has opened up new avenues for the treatment of eye diseases. DECLs is expected to partially overcome the shortcomings of eye drops due to single-dose packaging, accurate dosing, prolonged drug elution behavior, and simplified dosing procedures. Currently, a significant proportion of the DECLs design effort has been directed towards enhancing the compatibility of contact lenses with drugs. The appropriate elution time for the drug remains unclear. Additionally, it is ambiguous for which ophthalmic diseases DECLs offers the greatest therapeutic advantage. To rationally design DECLs in practice, it is necessary to understand the acceptance of DECLs by patients and practitioners and to clarify the indications for DECLs. This review will first focus on the acceptance of DECLs by different patients and practitioners and discuss the factors that influence its acceptance. Secondly, this review presents an overview of the current effectiveness of DECLs treatments in animals and in the clinical phase, with a particular focus on the suitability of DECLs for the treatment of ophthalmic diseases. Overall, patients and practitioners expressed positive attitudes towards DECLs. However, this is related to factors such as DECLs' treatment cycle, safety, and price. In addition, DECLs has good application prospects for ocular wound healing, postoperative management, and treatment of contact lenses-related complications. Furthermore, chronic diseases such as glaucoma that necessitate long-term medication and intraocular diseases that require implants or injections represent additional potential applications for DECLs. It is hoped that this review will facilitate a deeper understanding of DECLs acceptance and indications, thereby supporting the rational design of DECLs. At the same time, this review provides a reference for the design of other drug-device combination products.

Can AI Predict the Magnitude and Direction of Ortho-K Contact Lens Decentration to Limit Induced HOAs and Astigmatism?

Background: The aim is to investigate induced higher-order aberrations (HOA)s and astigmatism as a result of non-toric ortho-k lens decentration and utilise artificial intelligence (AI) to predict its magnitude and direction. Methods: Medmont E300 Video topographer was used to scan 249 corneas before and after ortho-k wear. Custom-built MATLAB codes extracted topography data and determined lens decentration from the boundary and midpoint of the central flattened treatment zone (TZ). An evaluation was carried out by conducting Zernike polynomial fittings via a computer-coded digital signal processing procedure. Finally, an AI-based machine learning neural network algorithm was developed to predict the direction and magnitude of TZ decentration. Results: Analysis of the first 21 Zernike polynomial coefficients indicate that the four low-order and four higher-order aberration terms were changed significantly by ortho-k wear. While baseline astigmatism was not correlated with lens decentration (R = 0.09), post-ortho-k astigmatism was moderately correlated with decentration (R = 0.38) and the difference in astigmatism (R = 0.3). Decentration was classified into three groups: ≤0.50 mm, reduced astigmatism by -0.9 ± 1 D; 0.5~1 mm, increased astigmatism by 0.8 ± 0.1 D; >1 mm, increased astigmatism by 2.7 ± 1.6 D and over 50% of lenses were decentred >0.5 mm. For lenses decentred >1 mm, 29.8% of right and 42.7% of left lenses decentred temporal-inferiorly and 13.7% of right and 9.4% of left lenses decentred temporal-superiorly. AI-based prediction successfully identified the decentration direction with accuracies of 70.2% for right and 71.8% for left lenses and predicted the magnitude of decentration with root-mean-square (RMS) of 0.31 mm and 0.25 mm for right and left eyes, respectively. Conclusions: Ortho-k lens decentration is common when fitting non-toric ortho-k lenses, resulting in induced HOAs and astigmatism, with the magnitude being related to the amount of decentration. AI-based algorithms can effectively predict decentration, potentially allowing for better control over ortho-k fitting and, thus, preferred clinical outcomes.

Drug Delivery Systems for Glaucoma: A Narrative Review.

Glaucoma is one of the world's leading causes of blindness, and its management is challenging. The main objective is to lower intraocular pressure through medical, para-surgical, and surgical therapy. Medical therapy often represents the first line of treatment. Although effective in many cases, the eye drops are accompanied by significant problems. They require high patient compliance and can be associated with various side effects, limiting their efficacy. Consequently, the research for new drug delivery systems trying to overcome these limitations is ongoing: numerous devices are developing and gradually entering clinical practice. These new therapeutic options may offer better control of the intraocular pressure, with fewer side effects, and are less dependent on patients' compliance. Hence, the research in this field continues to flourish. This review summarizes the most recent findings in the scientific literature, underlines the role and possible limitations of the new glaucoma drug delivery systems in clinical practice, and recognizes their new horizons and perspectives.

Ocular tear fluid biomarkers collected by contact lenses.

PURPOSE: To collect tear fluid biomarkers from contact lenses (CLs) and determine the impact of CL wear duration. METHODS: Rabbits were fitted with commercial etafilcon A CLs, which were collected after 1 min, 4 and 8 h (n = 4/time point). Tear fluid proteins and cytokines were extracted from the CLs and quantified. An exploratory comparison was performed between CLs and Schirmer Strips (SS) for a 1 min duration. RESULTS: The concentration of MUC5AC was significantly higher after 4 h of CL wear. The expression of all investigated cytokines (IL-1α, IL-1ß, IL-8, IL-17A, IL-21, Leptin, MIP-1ß, MMP-9, NCAM-1, and TNF-α) was detectable after 1 min of CL wear, and over time, all showed significant variations throughout the 8-h CL wear period. Notably, IL-1α significantly increased by 8 h of CL wear, while MMP-9 decreased. Albumin and lysozyme did not show significant variations with CL wear. Differences between CLs and SS after 1 min were statistically significant for albumin, Leptin, TNF-α, IL-1α, IL-1ß, and IL-8. CONCLUSIONS: The duration of CL wear significantly affects the collection of some tear fluid biomarkers. Albumin, MUC5AC, and cytokines may have individual and synergistic diagnostic or prognostic potential. CLs and SS were similar for lysozyme and MUC5AC but differed in the collection of albumin and some cytokines. CLs are a viable tear fluid collection method for biomarker analyses and can be immediately added as a routine clinical test by being FDA-approved medical devices.

Eumelanin-Enhanced Photothermal Disinfection of Contact Lenses Using a Sustainable Marine Nanoplatform Engineered with Electrospun Nanofibers.

Bacterial keratitis (BK) is a severe eye infection commonly associated with Staphylococcus aureus (S. aureus), posing a significant risk to vision, especially among contact lens wearers. This research introduces a novel smart nanoplatform (deMS@cNF), developed from demineralized mussel shells (deMS) and reinforced with chitin (CT) nanofibrils, specifically designed for portable photothermal disinfection of contact lenses. The nanoplatform leverages the photothermal properties of eumelanin in mussel shells (MS), which, when activated by a simple bike flashlight, rapidly heats to temperatures up to 95 °C, effectively destroying bacterial contamination. In vitro tests demonstrate that the nanoplatform is biocompatible and non-toxic, making it suitable for medical applications. This study highlights an innovative approach to converting marine biowaste into a safe, effective, and low-cost portable method for disinfecting contact lenses, showcasing the potential of the deMS@cNF platform for broader antimicrobial applications.

Tear levels of Transforming Growth Factor-ß1 and Interleukin 1-ß, and clinical correlations in new contact lens users.

PURPOSE: To assess alterations in the tear Transforming Growth Factor (TGF)-ß1 and Interleukin (IL1)-ß concentration in new contact lens wearers; and explore correlations with tear film stability, and ocular physiological response. METHODS: In this clinical setting, 12 neophytes (5 males), with an average age of 24.0 ± 5.0 years were fitted with delefilcon A contact lenses. Physiological responses (bulbar and limbal hyperemia), Pre-corneal (NIBUT), Pre-lens (PL-NIBUT) non-Invasive Break-Up Times, and tear samples were collected in the morning (before lens insertion; 9 - 10 a.m.) and afternoon (before lens removal; 7 - 8p.m.) of the same day. NIBUT and PL-NIBUT were measured using a tearscope. Tear samples were assayed for TGF-ß1 and IL1-ß concentrations using Enzyme-Linked Immunosorbent Assay kits. An 11-members control group (6 males) aged 25.0 ± 5.0, served to assess biomarker levels in non-contact lens wearers' tears. RESULTS: Subjects wore lenses for an average of 7 h and 20 min (range: 6 to 9 h). Bulbar and limbal hyperemia increased significantly throughout the day (p < 0.001). PL-NIBUT were lower than NIBUT (4.7 ± 2.0 Vs. 12.2 ± 8.8 s; p < 0.001). The IL1-ß levels were higher in neophytes than controls (3.2 ± 4.7 Vs. 0.1 ± 0.1 pg/ml; p = 0.05), correlating significantly with bulbar (r = 0.405, p = 0.008) and limbal hyperemia (r = 0.499, p = 0.027). No substantial changes were reported for TGF-ß1. CONCLUSION: The presence of TGF-ß1 in tears does not appear significantly affected by lens wear. The association between physiological parameters and IL1-ß levels suggests that lenses may disrupt ocular surface homeostasis by altering cytokine regulatory mechanisms. However, due to its low concentration, IL1-ß's role in the subclinical inflammatory response to lens wear is limited.

The clinical impact of contact lens wear on neural structure and function of the cornea.

Contact lens (CL) use is growing rapidly, with a current estimate of over 100 million wearers worldwide. Vast improvements in materials and designs have occurred over the past decades with advancements in the understanding of ocular surface health with CL wear. However, the potential impact of CL on neural structures and function of the ocular surface, particularly in relation to the richly innervated cornea, remain poorly understood. Problems with sensation such as CL discomfort and conditions that may be associated with lens wear including dry eye disease also remain pervasive. This narrative review discusses the findings from studies involving soft or rigid CL wearers, assessed with c linical techniques designed for examining the neural integrity of the cornea, namely in vivo confocal microscopy and esthesiometry. While the collective findings remain equivocal in terms of the changes in corneal nerve morphology and function with conventional CL wear, more specialised CLs, namely orthokeratology lenses, which mechanically manipulates the structure of the cornea seem to produce more prominent changes in nerve distribution and sensitivity reduction. Given the intricate relationship between neural and immune mechanisms in maintaining balanced ocular surface health, the potential links between these structural and functional findings with parainflammation and neuroinflammation, as well as clinical issues including CL discomfort and dry eye disease, are also explored.

Rational design of antibiotic-free antimicrobial contact lenses: Trade-offs between antimicrobial performance and biocompatibility.

Microbial keratitis associated with contact lenses (CLs) wear remains a significant clinical concern. Antibiotic therapy is the current standard of care. However, the emergence of multidrug-resistant pathogens necessitates the investigation of alternative strategies. Antibiotic-free antimicrobial contact lenses (AFAMCLs) represent a promising approach in this regard. The effectiveness of CLs constructed with a variety of antibiotic-free antimicrobial strategies against microorganisms has been demonstrated. However, the impact of these antimicrobial strategies on CLs biocompatibility remains unclear. In the design and development of AFAMCLs, striking a balance between robust antimicrobial performance and optimal biocompatibility, including safety and wearing comfort, is a key issue. This review provides a comprehensive overview of recent advancements in AFAMCLs technology. The focus is on the antimicrobial efficacy and safety of various strategies employed in AFAMCLs construction. Furthermore, this review investigates the potential impact of these strategies on CLs parameters related to wearer comfort. This review aims to contribute to the continuous improvement of AFAMCLs and provide a reference for the trade-off between resistance to microorganisms and wearing comfort. In addition, it is hoped that this review can also provide a reference for the antimicrobial design of other medical devices.

Long-Term Prevalence of Fungal Keratitis at a Swiss Tertiary Eye Clinic.

Fungal keratitis is a rare yet severe infection of the cornea. Fungal species distribution depends on the climate and socioeconomic status and can show regional variation. This retrospective single-center study was conducted at a tertiary eye care center and the collaborating Institute of Medical Microbiology in Switzerland. On investigating all fungal-positive corneal scrapings and contact lens assessments of patients with keratitis from January 2012 to December 2023, 206 patients were identified, of which 113 (54.9%) were female. The median age was 38 (IQR 29.8, [18-93]), and 154 (74.8%) applied contact lenses. The most commonly found pathogen was Candida spp., followed by Fusarium spp. Molds were 1.8 times more common than yeasts. Linear regression showed no significant increase or decrease in the infection rate over time (p = 0.5). In addition, 10 patients (4.9%) were found to have coinfections with Acanthamoeba, 11 (5.3%) with HSV-1, none with HSV-2, and 4 (1.9%) with VZV. This study provides a long-term overview of fungal-positive corneal scrapings and contact lens specimens of patients with fungal keratitis. Based on our results, coinfections with Acanthamoeba, HSV, and VZV are frequent, especially in patients wearing contact lenses. Thus, wearing contact lenses may facilitate coinfection in fungal keratitis.

Corrigendum: Binocular balance across spatial frequency in anisomyopia.

[This corrects the article DOI: 10.3389/fnins.2024.1349436.].

Polymerization of hydroxyethyl methacrylate (HEMA) under rotation to form core-annular hydrogels.

HYPOTHESIS: We propose to polymerize high water content hydroxyethyl methacrylate (HEMA) formulations in a rotating cylinder to explore the effect of the rotation on microstructure and critical parameters such as diffusivity of model proteins in porous poly-HEMA gels. EXPERIMENTS: Cylindrical molds were partially filled with water-HEMA-initiator-crosslinker mixtures and exposed to UV light while undergoing rotation to polymerize into a cylindrical tube. The process was repeated multiple times to manufacture a core annular rod with multiple concentric rings, in which at least one ring was porous. The porous gels were imaged by scanning electron microscopy to explore the microstructure. The transport of model proteins bovine serum albumin and human γ-globulin was measured and modeled, in radial and axial directions, to obtain the effective diffusivity and partition coefficient. Also, the true diffusivity of proteins was calculated by accounting for the effects of porosity and tortuosity. FINDINGS: The porous gels exhibited diffusion-controlled release of both model proteins. The hydrogels prepared with 55% water in the monomer mixture were porous with non-isotropic structure likely due to axially oriented pores with minimal radial connectivity. The gels with higher water content were isotropic with interconnected pores in both directions. The pore volume increased with water content, but the partition coefficient was relatively constant and less than one likely due to presence of isolated unconnected pores.

The Role of Pseudomonas aeruginosa in the Pathogenesis of Corneal Ulcer, Its Associated Virulence Factors, and Suggested Novel Treatment Approaches.

BACKGROUND: Pseudomonas aeruginosa (P. aeruginosa), is a diverse Gram-negative pathogen commonly associated with a wide spectrum of infections. It is indicated to be the most prevalent causative agent in the development of bacterial keratitis linked with the use of contact lens. Corneal infections attributed to P. aeruginosa frequently have poor clinical outcomes necessitating lengthy and costly therapies. Therefore, this review looks at the aetiology of P. aeruginosa bacterial keratitis as well as the bacterial drivers of its virulence and the potential therapeutics on the horizon. METHOD: A literature review with the articles used for the review searched for and retrieved from PubMed, Scopus, and Google Scholar (date last accessed 1 April 2024). The keywords used for the search criteria were "Pseudomonas and keratitis, biofilm and cornea as well as P. aeruginosa". RESULTS: P. aeruginosa is implicated in the pathogenesis of bacterial keratitis associated with contact lens usage. To reduce the potential seriousness of these infections, a variety of contact lens-cleaning options are available. However, continuous exposure to a range of antibiotics doses, from sub-inhibitory to inhibitory, has been shown to lead to the development of resistance to both antibiotics and disinfectant. Generally, there is a global public health concern regarding the rise of difficult-to-treat infections, particularly in the case of P. aeruginosa virulence in ocular infections. This study of the basic pathogenesis of a prevalent P. aeruginosa strain is therefore implicated in keratitis. To this effect, anti-virulence methods and phage therapy are being researched and developed in response to increasing antibiotic resistance. CONCLUSION: This review has shown P. aeruginosa to be a significant cause of bacterial keratitis, particularly among users of contact lens. It also revealed treatment options, their advantages, and their drawbacks, including prospective candidates.

Drug-impregnated contact lenses via supercritical carbon dioxide: A viable solution for the treatment of bacterial and fungal keratitis.

Keratitis is a corneal infection caused by various bacteria and fungi. Eye drop treatment of keratitis involves significant challenges due to difficulties in administration, inefficiencies in therapeutic dosage, and frequency of drug applications. All these are troublesome and result in unsuccessful treatment, high cost, time loss, development of drug resistance by microorganisms, and a massive burden on human health and the healthcare system. Most of the antibacterial and antifungal medications are non-water-soluble and/or include toxic drug formulations. Here, the aim was to develop drug-loaded contact lenses with therapeutic dosage formulations and extended drug release capability as an alternative to eye drops, by employing supercritical carbon dioxide (ScCO2) as a drug impregnation solvent to overcome inefficient ophthalmic drug use. ScCO2, known as a green solvent, has very low viscosity which provides high mass transfer power and could enhance drug penetration into contact lenses much better with respect to drug loading using other solvents. Here, moxifloxacin (MOX) antibiotic and amphotericin B (AMB) antifungal medicines were separately loaded into commercially available silicone hydrogel contact lenses through 1) drug adsorption from the aqueous solutions and 2) impregnation techniques via ScCO2 and their efficacies were compared. Drug impregnation parameters, i.e., 8-25 MPa pressure, 310-320 K temperature, 2-16-hour impregnation times, and the presence of ethanol as polar co-solvent were investigated for the optimization of the ScCO2 drug impregnation process. The highest drug loading and long-term release kinetic from the contact lenses were obtained at 25 MPa and 313 K with 2.5 h impregnation time by using 1 % ethanol (by volume). Furthermore, antibacterial/antifungal activities of the MOX- and AMB-impregnated contact lenses were effective against in vitro Pseudomonas aeruginosa (ATCC 10145) bacteria and Fusarium solani (ATCC 36031) fungus for up to one week. Consequently, the ScCO2 method can be effectively used to impregnate commercial contact lenses with drugs, and these can then be safely used for the treatment of keratitis. This offers a sustainable delivery system at effective dosage formulations with complete bacterial/fungal inhibition and termination, making it viable for real animal/human applications.

Effect of Light Sources on Transmittance of Commercially Available Contact Lenses.

BACKGROUND: Previous studies have suggested that light rays may interact with contact lenses, potentially affecting their transmittance. AIM: This study aimed to investigate the effects of visible and ultraviolet (UV)-A light sources on the transmittance of some commercially available daily, weekly, and monthly contact lenses. METHODS: Nine commercially available soft contact lenses were irradiated with a solar simulator, light-emitting diode (LED) source, laser source, and UV-A source. The average transmittance of the tested lenses before and after irradiation in the UV, visible, and infrared light wavelength ranges was determined using an Agilent UV-visible spectrophotometer, model 8453. RESULTS: The results showed a partial or complete block of UV transmission at the UV-B region (300 nm) and the UV-A region (355 nm) by the Bio true daily contact lens, as well as the Acuvue Oasys, Avaira, and Biomedics 55 weekly lenses. At the visible region (555 nm), irradiation of the contact lenses by different light sources resulted in reduced light transmittance. At the infrared region (900 nm), the weekly and monthly contact lenses partially blocked infrared transmission, while the daily lenses showed either increased or decreased infrared transmission. CONCLUSIONS: Solar and artificial lighting, as well as high-powered lasers, constitute a major concern on the contact lenses' light transmission and optical properties. It is essential to develop soft contact lenses that have photoprotective properties while maintaining visible light transmittance.

Scleral Lenses for Managing Dry Eye Disease in the Absence of Corneal Irregularities: What Is the Current Evidence?

Scleral lenses (SLs) are large-diameter rigid contact lenses that are a mainstay treatment for eyes with corneal irregularities. In recent years, there has been increased interest in the role of managing dry eye disease (DED) with SLs, as many patients with DED have reported symptomatic relief with SL wear. The role of SLs for DED management when there are associated corneal irregularities is supported by individual case reports and studies. This has prompted practitioners to begin advocating using SLs in DED cases, even in the absence of associated corneal irregularities and other ocular surface diseases (OSDs). There have also been discussions on potentially placing SLs earlier in the treatment hierarchy of DED, where it currently sits at a more advanced level of intervention (Step 3) in the TFOS DEWS II Report. This review will present the currently available, albeit sparse, evidence that supports and suggests this practice, as well as ancillary evidence supporting the purported benefits of SL wear in DED. The advantages of SL wear, such as corneal healing, absence of tear evaporation and contact lens dehydration, and improved visual acuity with associated increased wear comfort, and how this will benefit DED patients will be explored. Conversely, the challenges associated with fitting SLs in DED patients, including increased midday fogging, poor wettability, and subjective patient satisfaction, will also be presented, as well as a discussion on the key considerations for SL fitting in this population. Overall, while more research is needed to support the use of SLs in DED patients without associated corneal irregularities and other forms of OSD, the use of these lenses may prove to have a potentially wider role given their reported ancillary benefits in these populations.

Sustained descemetocele management with Prosthetic Replacement of the Ocular Surface Ecosystem (PROSE) treatment.

Purpose: To report a case of a 67-year-old male who was successfully managed over a 7-year period for descemetocele secondary to ocular graft versus host disease (oGVHD) using Prosthetic Replacement of the Ocular Surface Ecosystem (PROSE) treatment. Observations: We previously reported on a patient managed with a PROSE device for severe dry eyes secondary to oGVHD, who subsequently developed a central corneal descemetocele. The patient was deemed a poor surgical candidate due to limbal stem cell deficiency secondary to oGVHD. Therefore, we elected to closely monitor the descemetocele as the patient continued PROSE therapy. The patient's descemetocele has been managed successfully without perforation throughout a 7-year follow-up period with corrected distance visual acuity remaining stable at 20/50 in the affected eye. Conclusions and importance: Descemetoceles are an uncommon complication of ocular graft versus host disease. This is the longest published report of a corneal descemetocele managed with PROSE. Our report suggests that in appropriate patients who are at high-risk for post-surgical complications, PROSE in conjunction with other medical management should be considered as an alternative to corneal transplantation.

Biomechanical evaluation of different plunger size and plunger position on removing soft contact lenses and rigid gas permeable contact lenses.

BACKGROUND: To avoid risks of mucosal infection from contact lenses removal, a contact lens plunger is often used. OBJECTIVE: Given various types of contact lens plungers available on the market, no study has yet been done on mechanical effects of the contact lens plunger on contact lens removal. Here, this study used finite element analysis to investigate the effects of plunger size and plunger position on the removal of soft and rigid gas permeable (RGP) contact lenses. METHODS: First, we established finite element analysis models for the plunger, contact lens, cornea, and aqueous humor. The plunger is made of mostly silicone rubber, and the contact lenses are mainly made of soft and hard material. The part of the plunger used for removal was located either at the central or the edged position, with pulling 1 mm distance. The main parameters observation indicators of in this study were the reaction force at the fixed end of the cornea, aqueous humor, the von Mises stress of the plunger, the contact lenses, and the cornea. RESULTS: Results of this study showed that when a plunger of a larger diameter was used, the reaction force of the plunger was also larger, especially when applied to RGP lenses, which required a slightly larger force (∼0.27 N). Also, when removing a RGP lens from the edge, there was a greater stress at the edge of the contact lens (2.5799 MPa), and this caused a higher stress on both the cornea (0.0165 MPa) and the aqueous humor (0.00114 MPa). CONCLUSIONS: When using a plunger with a larger diameter to remove a RGP lens, although a larger force required, the relatively larger contact area likely reduced the stress on the cornea and aqueous humor, thereby reducing the risk of eye injury. In addition, when removing a RGP lens, the results of this study recommended it to be removed from the plunger edge, as that facilitated the removal of contact lens.