Contact Lens Research Articles

Scleral lens fitting after paediatric limbal dermoid removal

Purpose. This case report describes the management of refractive error and amblyopia using a scleral lens fitted to the eye of a young child with an irregular cornea resulting from limbal dermoid removal and corneal transplant in infancy. Material and Methods. A young infant was initially fitted with spectacles and occlusion therapy following the surgical excision of a limbal dermoid and full thickness corneal transplant. The vision did not improve in spite of patching so the child was referred for contact lens fitting. Various iterations of scleral lens fitting were carried out. Results. Scleral lens fitting was attempted from the age of 2 years but transplant rejections, the COVID-19 pandemic and variable cooperation meant that adequate lens wear could not be achieved in the early stages. In addition, the corneal shape changed during the course of the fitting. During these periods, spectacle wear and occlusion therapy were maintained until a good lens fit could be achieved following several modifications. Treatment is ongoing but at the age of 5 years, the visual acuity is 0.24 logMAR letters. Conclusion. Scleral lenses can be used to habilitate the vision in an eye with an irregular cornea but when scleral lens wear is not possible, it is important to persevere with spectacle correction and patching therapy. Several iterations of scleral lenses may be needed as the eye changes and the child grows.

Enhancing Performance of Silicone Hydrogel Contact Lenses with Hydrophilic Polyphenolic Coatings

This study explores the application of a dopamine-assisted co-deposition strategy to modify the surface of daily disposable silicone hydrogel contact lenses. Aiming to enhance the hydrophilicity of these typically hydrophobic lenses, we developed an industry-friendly process using simple dip coating in aqueous solutions. By co-depositing tannic acid, dopamine and chitosan derivative and employing periodate oxidation, we achieved a rapid and efficient coating process. High-molecular-weight branched polyethylene imine was introduced to promote surface reactions. The resulting lenses exhibited extreme hydrophilicity and lipid repellency without compromising their intrinsic properties or causing cytotoxicity. While the coating demonstrated partial antimicrobial activity against Gram-positive Staphylococcus aureus, it offers a foundation for the further development of broad-spectrum antimicrobial coatings. This versatile and efficient process, capable of transforming hydrophobic contact lenses into hydrophilic ones in just 15 min, shows significant potential for improving comfort and performance in daily disposable contact lenses.

Referral Pattern and Comanagement of Patients With Keratoconus in West Africa: A Survey-Based Study of Optometrists in Ghana and Nigeria.

To investigate the referral and management patterns of patients with keratoconus among primary eye care practitioners in Ghana and Nigeria. A questionnaire adapted from previous studies was modified and created using Google Forms. The online survey was distributed to prospective participants using e-mails and other social media platforms. Data were analyzed using the Statistical Product and Service Solutions software (version 25.0; IBM Corp, Armonk, NY; Released 2017). One hundred and sixty-nine optometrists responded to the survey (61.54% from Nigeria and 38.46% from Ghana). Most (88.6%) practiced without corneal topographers. Most respondents (77.7%, n=136) reported not fitting rigid gas-permeable (RGP) contact lenses in a year and 68% were willing to refer for contact lens fitting to another practitioner. The major barriers to RGP fitting were lack of experience (44.4%, n=72), cost to practice (15.4%, n=25), and other reasons (12.4%), whereas 27.8% (n=45) preferred not to answer. Seventy-six percent of respondents (n=133) were willing to fit RGPs if the respondents received the training to do so. About half of the respondents (53.8%) reported progression of cornea signs as the reason for referral to an ophthalmologist. Half of the respondents (n=51.4%) did not have a cornea surgeon in the area the respondents practiced, and 76.3% reported not comanaging patients at all with ophthalmologists. This study highlights the current standard of care of patients with keratoconus in West Africa. The findings from this study suggest that clinical guidelines and further training of eye care practitioners in West Africa are needed to better manage patients with keratoconus.

Clinical Issues — November 2024

THIS MONTH Reducing the perioperative carbon footprint Key words: sustainability, carbon footprint, greenhouse gas (GHG), energy, consumption. Exsanguination before tourniquet use Key words: elastic wrap, exsanguination, gravity, pneumatic tourniquet, limb. Using augmented reality technology in the OR Key words: augmented reality (AR), virtual reality (VR), extended reality (XR), headset, navigation. Patients wearing contact lenses during a procedure Key words: contact lens, corneal abrasion, patient positioning, eye injury, risk factors.

See‐Through Conformable Holographic Metasurface Patches for Augmented Reality

AbstractCurrent requirements for augmented reality (AR) applications demand the use of dedicated AR glasses, which often need custom prescription lenses or contact lenses to correct common visual impairments, thus limiting AR's broader experiences. Here, an innovative methodology for the design, fabrication, and comprehensive analysis of a flexible, reflective‐type holographic metasurface patch designed for AR applications is presented. By fabricating a conformable metasurface on a transparent and flexible substrate, a prototype of AR eyeglasses is successfully created, capable of transforming everyday eyewear into AR glasses. The prototype is tested under both indoor and outdoor conditions, proving its effectiveness in delivering immersive AR imaging presentations. The metasurface's compact size does not interfere with normal vision. This approach increases the relevance and applicability of AR technology by making AR experiences accessible to a wider audience.

Myopia control with orthokeratology lenses. A 3-year follow-up study including a cross-over design: Clinical study Of Near-sightedness; TReatment with Orthokeratology Lenses 2 (CONTROL2 study).

The purpose of this study is to investigate 3-year efficacy of orthokeratology lenses (OKL) in controlling axial length progression in myopic Scandinavian children. Through a cross-over design of the control group to compare the treatment efficacy in younger versus older children, with the latter having higher cycloplegic spherical refractive error (cSEQ) at treatment initiation. Further, the study aimed to evaluate the safety of the treatment. This was a continuation of the randomized controlled study Clinical study Of Near-sightedness; TReatment with Orthokeratology Lenses (CONTROL study) in which the follow-up period of the original intervention group, that received OKL, was extended from 18 months to 36 months. Meanwhile, the original control group was crossed-over to OKL after the 18-month follow-up visit and treated for 18 months. Biometry was measured using Lenstar LS900, and contact lens complications were graded according to Efron Grading Scale for Contact Lens Complications (Efron score). Mixed models were used for statistical analysis. Nineteen subjects in the OKL group and 28 in the control group completed the CONTROL study. Hereof, 17 and 24 subjects from the OKL group and control group, respectively, agreed to participate in the CONTROL2 study. In the OKL continue group, the treatment efficacy did not decline during the 3-year study period (p-values for follow-up visits were all ≥0.82). There was no statistically significant difference between treatment efficacy when OKL treatment was initiated in younger versus older children (p-value ≥0.14 for all follow-up visits). Low-grade corneal staining was seen in several subjects at some point during the study, but here were no treatment-requiring or sight-threatening adverse events during the study period. The efficacy of myopia control by OKL was stable during 3 years of treatment. Similar treatment efficacies were found regardless of the age at treatment initiation. No severe adverse events occurred during the study period.

Effects of Rebamipide for Dry Eye on Optical Quality and Efficacy: A Systematic Review and Meta-Analysis.

Purpose: To evaluate the effects of rebamipide ophthalmic suspension on optical quality and efficacy of patients with dry eye under different conditions. Methods: A comprehensive search across five databases (PubMed, Cochrane Library, Web of Science, China National Knowledge Infrastructure, and Wan Fang) was conducted for studies published through May 13, 2024, focusing on rebamipide for dry eye treatment. Results: A total of 11 studies including 334 patients with dry eye were included. Tear breakup time (TBUT) values of patients with dry eye increased significantly after 2 weeks (standardized mean difference [SMD] =1.07, 95% confidence interval [CI] = [0.05, 2.09]), 4 weeks (SMD = 1.26, 95% CI = [0.77, 1.75]), and 12 weeks (SMD = 1.04, 95% CI = [0.37, 1.71]) of rebamipide treatment. Subgroup analysis revealed that patients with dry eye wearing soft contact lens (SCL) exhibited higher TBUT values after 4 weeks of rebamipide treatment compared with those who received rebamipide alone. In addition, rebamipide significantly improved fluorescein staining score of patients with dry eye after 4 weeks of treatment (SMD = -0.34, 95% CI = [-0.63, -0.06]). However, 4 weeks of rebamipide treatment showed no significant effect on Schirmer I test values (SMD = -0.04, 95%, CI = [-0.43, 0.35]) and higher-order aberrations (SMD = -0.73, 95% CI = [-1.77, 0.30]). Conclusions: These results indicate a significant improvement in the efficacy of rebamipide treatment for patients with dry eye, particularly for those wearing SCL. The effect of rebamipide on visual quality was found to correlate with the underlying dry eye status.

Keratoconus.

Keratoconus is a progressive eye disorder primarily affecting individuals in adolescence and early adulthood. The ectatic changes in the cornea cause thinning and cone-like steepening leading to irregular astigmatism and reduced vision. Keratoconus is a complex disorder with a multifaceted aetiology and pathogenesis, including genetic, environmental, biomechanical and cellular factors. Environmental factors, such as eye rubbing, UV light exposure and contact lens wearing, are associated with disease progression. On the cellular level, a complex interplay of hormonal changes, alterations in enzymatic activity that modify extracellular membrane stiffness, and changes in biochemical and biomechanical signalling pathways disrupt collagen cross-linking within the stroma, contributing to structural integrity loss and distortion of normal corneal anatomy. Clinically, keratoconus is diagnosed through clinical examination and corneal imaging. Advanced imaging platforms have improved the detection of keratoconus, facilitating early diagnosis and monitoring of disease progression. Treatment strategies for keratoconus are tailored to disease severity and progression. In early stages, vision correction with glasses or soft contact lenses may suffice. As the condition advances, rigid gas-permeable contact lenses or scleral lenses are prescribed. Corneal cross-linking has emerged as a pivotal treatment aimed at halting the progression of corneal ectasia. In patients with keratoconus with scarring or contact lens intolerance, surgical interventions are performed.

The Assessment of Dry Eye Syndrome in Relation to the Use of Contact Lenses in the Jazan Region of Saudi Arabia: A Cross-Sectional Study

The Assessment of Dry Eye Syndrome in Relation to the Use of Contact Lenses in the Jazan Region of Saudi Arabia: A Cross-Sectional Study

Visual and ocular surface benefits of mini-scleral contact lenses in patients with chronic ocular graft-versus-host disease (GvHD)

Graft-versus-Host disease is a major complication of allogeneic stem cell transplantation. The eyes are a frequently affected organ with a severe dry eye disease being the hallmark manifestation. This retrospective study evaluates the effect of mini-scleral contact lenses on visual acuity, eye-related quality of life and the ocular surface. 62 eyes of 31 patients were included and visual acuity, ocular surface disease index (OSDI) questionnaire results and Oxford grades before and after mini-scleral lens fitting were compared. Median Snellen fraction with mini-scleral lenses was 20/25 (1st 20/30/3rd 20/20) compared to 20/40 median Snellen fraction with spectacles (1st 20/60/3rd 20/25). Median OSDI scores improved from 73 (1st 41.6/3rd 89) before fitting to 27 (1st 14.5/3rd 56) with mini-scleral lenses. Median Oxford grade decreased from 3 before mini-scleral lens fitting (1st 1/3rd 4.75) to 1 after mini-scleral lens fitting (1st 0/3rd 4). Median time of follow up was 717.5 days. Seven patients (22.6%) discontinued therapy with mini-scleral lenses. Mini-scleral lenses are beneficial for most patients with ocular GvHD as they improve visual acuity, eye-related quality of life and the integrity of the corneal epithelium.

Hand-Washing Habits in a Sample of Spanish Soft Contact Lens Wearers.

Contact lens (CL) wear is a safe method for the correction of refractive errors. However, rare, severe ocular complications may occur which may lead to visual loss. As most of these complications are related to poor patient compliance with care and maintenance instructions, resulting in the contamination of hands, CLs and accessories, it was the purpose of this study to assess hand-washing habits in a sample of Spanish soft CL wearers. Hand hygiene was explored through a self-reported online survey and via an in-office practical demonstration in a subset of those users answering the survey. A total of 198 surveys were analyzed, and 18 CL users participated in the practical demonstration. Overall, hand-washing habits were not adequate, with 35 (17.8%) and 103 (52.2%) participants reporting not always washing their hands prior to CL or storage case manipulation, respectively. While 161 (81.3%) participants dried their hands after washing, 132 of these (82.1%) used non-disposable cloth towels. Participants receiving specific hand-washing information from their practitioners (141, or 71.1%) had better hand hygiene (p < 0.05). During the practical demonstration, 13 (72.2%) participants used water and soap to wash their hands, but only 3 (16.7%) displayed correct hand washing routines. Complete patient education, as well as practical reminders at all follow-up visits, are essential to ensure better hand hygiene in order to reduce the probability of ocular complications and to guarantee safe and satisfactory CL use.

Knowledge and Practice of Contact Lens Users in Eastern Province, Saudi Arabia

Knowledge and Practice of Contact Lens Users in Eastern Province, Saudi Arabia

A Piezoresistive-Based Contact Lens for Non-invasive Intraocular Pressure Measurement

A Piezoresistive-Based Contact Lens for Non-invasive Intraocular Pressure Measurement

Hydrogel-Embedded Polydimethylsiloxane Contact Lens for Ocular Drug Delivery.

Topical administration is the commonly preferred method of administering ophthalmic formulations, with the majority of available medications in the form of eye drops or ointments. However, the topical application of ophthalmological medications has less bioavailability and a short residence time because of the physiological and anatomical constraints of the eye, making efficient ophthalmic drug delivery a challenging task. Microfluidic contact lenses have the advantage of delivering drugs into the eye in a controlled and on-demand manner. Here, we showcase the use of hydrogel-embedded microcavities on PDMS-based contact lenses for ocular drug delivery applications. The fabrication technique adopted here is the spontaneous formation of the spherical cavity by hydrogel monomer droplet, followed by the simultaneous thermal curing of hydrogel and PDMS, creating a spherical cavity as small as 150 μm. The spherical cavity is embedded with pH-responsive hydrogel for on-demand drug delivery. The drug loaded in the hydrogel matrix is released into the ocular environment by diffusion. The spherical cavity with a narrow opening restricts the diffusion to a minimum under normal ocular pH conditions(pH > 6). When the ocular pH reduces (pH < 6), the pH-responsive hydrogel inside the spherical cavity deswell and accelerates the drug release.

Harmonização estética do sorriso com lentes de contato dental: relato de caso

The harmonic smile has taken most patients to the dental office, which becomes a challenge for the Dental Surgeon. Among the various existing techniques for restoring anterior teeth, contact lenses are currently the most sought after. Thus, in this case, the objective was the report that addresses a rehabilitation through 20 ceramic laminates, in a 51-year-old patient, who sought care at the Faculty of Amazonas - IAES. The therapeutic option was discussed with the patient, aiming at the benefits of porcelain, and it was chosen. After previous procedures, the elements were prepared and adapted to receive the porcelain, where there was a minimally invasive preparation, respecting the patient's entire dental structure. This procedure generated better self-esteem and confidence when talking, smiling and eating, considering the cost-effectiveness of the chosen material.

Axis "microbiota – gut – eye": a review

Every organ in the human body has its own microbiota, and the eye, a complex multi-component organ, is no exception. Due to the limitations of traditional methods, detailed study of the ocular microbiome began only in 2010 as part of the Eye Microbiome Project, when advances in research methods made it possible to obtain detailed data, although there had been debate previously about whether microorganisms were even able to attach to the ocular surface due to the layers of the tear film, which have antibacterial properties. The cornea, conjunctiva, lacrimal glands and tear film, meibomian glands and microbiome form the microenvironment of the ocular surface, interacting together and resisting irritants, allergens and pathogens. Homeostasis of the ocular microbiota is critical for maintaining the health of the visual organ. Most microorganisms are found on the cornea and conjunctiva, and modern research methods, including 16S rRNA sequencing, have allowed us to establish the "core" of the ocular surface microbiota, identifying the most common types: Staphylococcus, Corynebacterium, Propionibacterium, and Streptococcus, although the exact composition of the “core” remains debatable. Many factors can influence the composition of the microbiome, including age, contact lens wear, ophthalmic medications, and antibiotics. Like the microbiome of many other organs, the ocular surface microbiome is influenced by the gut microbiome: this relationship has been called the "microbiota – gut – eye" axis. Within the "gut – eye" axis, healthy gut microbiota produce short-chain fatty acids, indoles, polyamines, and other substances that have a beneficial effect on the immune system and retinal health. The state of dysbiosis leads to disruption of homeostasis, and the increasing inflammatory reaction can contribute to damage to the optic nerve and progression of eye disease. Some ophthalmologic diseases, such as diabetic retinopathy, age-related macular degradation, choroidal neovascularization, uveitis, primary open-angle glaucoma, Sjogren's syndrome, dry eye syndrome are associated with dysbiosis of the intestinal microbial composition. Correction of intestinal dysbiosis using various methods can lead to a decrease in the risk of eye diseases, although additional research is needed to discover new methods for treating ophthalmologic pathologies along the "microbiota – gut – eye" axis.

Sustained release of proteins from contact lenses with porous annulus.

Ophthalmic drugs are administered to the front of the eye by eyedrops. The bioavailability of drugs delivered via eye drops is low due to tear turnover. Contact lenses can address some deficiencies of eye drops by sustaining the delivery of drugs, but commercial contact lenses have small pore sizes that cannot load biologics, which are becoming more common for treating ophthalmic diseases. This study aims to investigate novel poly(hydroxyethyl methacrylate) (pHEMA) lenses with transparent center and porous annulus for sustained release of model proteins. A novel hydrogel polymerization process was used to fabricate concentric, porous layer pHEMA hydrogel rods. The hydrogels were lathe cut into contact lenses which were explored for the delivery of proteins and gold nanoparticles. Lenses were characterized by partition coefficient and diffusivity, which was estimated by fitting experimental data to an analytical model. Transmittance measurements were made to compare transparency of porous lens centers to commercial contact lenses. Porous pHEMA lenses consisting of a concentric, porous layer made from 55% water content in precursor were successfully lathe cut into lenses with transparent center and opaque porous annulus. The porous lenses could load large model proteins of bovine serum albumin and human γ-globulin and provide sustained release. The core annular pHEMA contact lenses consisting of an outer annulus of opaque, porous pHEMA and an inner, center layer of clear, nonporous pHEMA can provide sustained delivery of biologics.

Prevalence of dry eye disease symptoms, associated factors and impact on quality of life among medical students during the pandemic

This cross-sectional study aimed to evaluate the prevalence of dry eye disease (DED) symptoms, their associated factors, and the impact on quality of life (QOL) and mental health among medical students during the COVID-19 pandemic using online surveys. Participants completed questionnaires covering demography, medical history, and personal data. The Thai version of the Dry Eye-related Quality-of-Life Score (DEQS-Th) was used for DED screening. The QOL and mental health challenges (support, coping, stress, and depression) were evaluated by the EuroQoL-5 dimensions-5 levels (EQ-5D-5L) and Thymometer questionnaires. A total of 449 participants were analyzed, with a mean age of 21.8 years and 61.5% female. The prevalence of DED symptoms was 60.4% (95%CI 55.7–64.8). The DEQS-Th score, the EQ-5D-5L score, and all aspects of mental health challenges were significantly worse in DED participants compared to non-DED participants. Associated factors for DED symptoms included preexisting DED (p = 0.001), refractive errors (p = 0.007), allergic conjunctivitis (p = 0.001), artificial tears use (p < 0.001), and decreased EQ-5D-5L score (p < 0.001). This study highlighted the high prevalence of DED symptoms among medical students during the pandemic and its negative impact on QoL and mental health. Notably, female gender, contact lens wear, screen time, and mask-wearing duration were not associated with DED symptoms.

Patient evaluated economic impact of keratoconus in New Zealand

ABSTRACT Clinical relevance Few studies have investigated the economic burden of keratoconus to patients and society including a patient’s lifetime expenditure. Analysing disease cost is important in advocating funding and planning for appropriate management and treatment. Background Keratoconus can be an expensive disease, including costs associated with visual rehabilitation and surgery. This study aimed to assess direct and indirect expenditures incurred by keratoconus subjects, to estimate the lifetime per capita cost and the total costs of keratoconus per year in Auckland, New Zealand. Methods A cross-sectional study where participants with keratoconus were recruited from public and private clinics to complete an anonymous questionnaire. A keratoconus health expenditure questionnaire was used to assess direct and indirect expenditures for participants. Estimated lifetime per capita costs and total direct and indirect costs associated with keratoconus were calculated. Results Responses from 110 participants were recorded. Most participants (55.5%) were between the ages of 21 and 30, 59.1% were male, and Pacific People were over-represented (14.5%) compared to the national population. The prevalence of visual rehabilitation was low with 74.5% of participants never wearing contact lenses and 32.7% of subjects wearing spectacles purchased over 24 months prior. Few participants (26.5%) had subsidised care, including private health insurance with optical cover or the contact lens subsidy. Total direct and indirect costs are estimated to be NZD 30.9 million per year with an estimated lifetime per capita out-of-pocket cost of NZD 79,254. Conclusion Subjects with keratoconus experience significant direct and indirect costs with limited subsidisation from the government and private health insurance. The significant out-of-pocket costs required for managing keratoconus are likely a significant barrier to accessing appropriate visual rehabilitation in New Zealand.

Therapeutic Contact Lenses for Intraocular Drug Administration: Innovations and Applications in Treating Fungal Keratitis

This review examines the advancements in ocular medication administration, focusing on therapeutic contact lenses (TCLs) as a novel approach for treating fungal keratitis. Traditional eye Drops' bioavailability is poor due to various anatomical and physiological barriers, necessitating frequent administration and leading to poor patient compliance. TCLs offer a promising alternative, providing extended drug release, improved bioavailability, and enhanced patient comfort. This review explores different antifungal drugs, innovative methods for drug incorporation into TCLs, and their therapeutic efficacy. The potential of TCLs to revolutionize ocular drug delivery and improve treatment outcomes for fungal keratitis is discussed.