Lens Wear Research Articles

Variation of Bruch's membrane opening in response to intraocular pressure change during scleral lens wear, in a population with keratoconus.

The present study aimed to determine the potential impact of scleral lenses on intraocular pressure (IOP) by analysing the Bruch's membrane opening-minimum rim width (BMO-MRW) while the lenses are worn, in a population with keratoconus. Participants were required to have keratoconus and be successfully fitted with scleral lenses for at least 3 months. A new pair of optimised scleral lenses was provided before the study. During the first session, corneal biomechanics was assessed using an air tonometer, coupling Scheimpflug technology. Then, a scan of the optic nerve was carried out using optical coherence tomography (OCT) at 2 h intervals for 6 h. Particular attention was paid to identifying the BMO-MRW, which represents the smallest distance between the BMO and the internal limiting membrane. These tests were repeated, respecting the time at which the initial measurements were taken, while the scleral lens was worn. Results from only one eye were analysed. A statistically significant change of 10.5 ± 3.6 μm (95% CI [241.3-473.1]; p = 0.02) in BMO-MRW was observed after 6 h of scleral lens wear, compared to measurements without lenses (4.8 ± 3.4 μm; 95% CI [285.1-439.7]; p = 0.18). The fluctuation was greater in participants with keratoconus than found in a previous study of regular corneas. BMO-MRW became significantly thinner after 6 h of scleral lens wear compared with measurements without lenses. These variations may be associated with a rise in IOP during lens wear. Close monitoring for optic head changes should be carried out for patients at risk. These results should be compared with future longer-term studies including a larger cohort of patients.

International trends in prescribing multifocal and monovision soft contact lenses to correct presbyopia (2000–2023): An update

PurposeNumerous multifocal soft contact lenses have been introduced into clinical practice over the past half century. The purpose of this work is to update earlier surveys by describing international trends in multifocal and monovision soft lens fitting for presbyopia between 2000–2023, inclusive. MethodAn annual contact lens prescribing survey was sent to eye care practitioners in up to 71 countries between 2000–2023. Data relating to 52,580 soft daily wear lens fits to presbyopes (those ≥45 years of age) undertaken in 20 countries returning reliable longitudinal data were analysed in respect of multifocal and monovision soft daily wear lens fits. ResultsOverall, multifocal and monovision soft daily wear lens prescribing to presbyopes has more than doubled over the course of this survey, from 26.4 % of standard soft daily wear lens fits in 2000 to 61.1 % in 2023 (p < 0.0001). There were significant differences between countries in presbyopia soft daily wear lens prescribing (p < 0.0001). Of all soft daily wear fits to males, 45.1 % were multifocal and monovision soft lenses, compared with 52.7 % for females (p < 0.0001). When considered as the proportion of lenses fitting by age, multifocal soft lens fitting peaked between 50–65 years, followed by a precipitous drop until 85–90 years of age, and then an increase beyond 90 years of age. Analysis of 13,014 recent soft lens fits to presbyopes (2019–2023) revealed the following fitting proportions: multifocal lenses – 51 %; monovision – 10 %; and non-presbyopia fitting – 39 %. ConclusionThere has been a substantial increase in soft contact lens correction of presbyopia using multifocal and monovision corrections throughout the 24 years of this survey. A significant number of soft contact lens-wearing presbyopes are not receiving a presbyopia contact lens correction.

Decision-making tree to support sustainable waste management in optometric clinical practice and healthcare training programmes

ABSTRACT Clinical relevance Waste management strategies are well documented for employee safety, legal compliance and infection control measures; however, appropriate waste disposal is equally important to minimise adverse environmental impacts. Knowledge on best practices related to the disposal of healthcare-generated waste is crucial for environmental sustainability. Background Global healthcare contributes significantly to greenhouse gas emissions, thereby extending the pervasiveness of climate change. Urgent action is required by the healthcare sector to minimise these impacts. Proper waste management is an alleviation measure that can be easily implemented in healthcare practice. The aim of this study was to calculate the approximate mass of plastic waste generated through lens wear and develop an easy-to-use decision-making tree to support optometrists with sustainable waste management. Methods Data were analysed, from an online survey directed to ophthalmic lens wearers, to determine the mass of annual plastic waste associated with lens wear. Information collated from published studies and clinical experience of the researchers, supplemented by a literature search from online databases, EBSCOhost, Google Scholar, ScienceDirect and PubMed, were used to develop the waste decision-making tree. Results Approximately 48 kg of plastic waste was generated from annual lens wear, of which approximately 83% of recyclable materials were landfilled. The waste management decision-making tree was created to guide optometrists regarding sustainable waste management practices. Conclusion Although this study focused on Optometry, its findings and recommendations have applicability across the healthcare field. Environmental stewardship is a joint responsibility of all healthcare professionals. This study highlighted the importance of incorporating and promoting sustainable clinical measures as well as the embedding and regular updating of clinical evidence on waste management best practices into healthcare training programmes. In doing so, the broader healthcare sector can contribute significantly towards reducing healthcare waste and associated emissions and improving health outcomes, thereby safeguarding the planet and its inhabitants.

Incidence of microbial keratitis associated with overnight orthokeratology: a multicenter collaborative study.

To investigate the incidence of microbial keratitis among Japanese patients wearing orthokeratology (ortho-k) lenses STUDY DESIGN: Retrospective multicenter study METHOD: This study was conducted at 4 hospitals in Japan and involved 1438 patients who had been prescribed ortho-k lenses and had worn them for at least 3 months. Data on patient demographics, lens characteristics, lens care systems, and presence of microbial keratitis were extracted from the medical records. Duration of ortho-k lens wear was calculated from the original fitting date to the patient's last visit, with the total years of lens wear used as person-years of lens wear. The incidence of microbial keratitis was calculated by dividing the number of infected cases by the total person-years of lens wear for all enrolled participants. Among the 1438 patients, 753 were male and 685 were female, with a mean age of 12.7 ± 5.4 years. The mean duration of ortho-k lens wear was 5.2 ± 4.5 years, and the mean lens power was -3.52 ± 1.41 D. The total person-years of lens wear for all enrolled patients was 7415. Four cases of microbial keratitis were identified, resulting in an overall incidence of microbial keratitis of 5.4 (95% CI: 1.0-9.8) per 10,000 patient-years among ortho-k lens wearers. This study represents the largest sample size to date for estimating the incidence of microbial keratitis associated with ortho-k lenses. The incidence was similar to or slightly lower than that of previous studies on ortho-k-related microbial keratitis and also comparable to that of daily wear soft contact lenses.

Slowing myopia progression with cylindrical annular refractive elements (CARE) spectacle lenses-Year 1 results from a 2-year prospective, multi-centre trial.

To evaluate the effectiveness of 12 months of spectacle lens wear incorporating cylindrical annular refractive elements (CARE) in slowing myopia progression compared to single vision (SV) spectacle wear. In an ongoing 2-year prospective, double-masked, multi-centre clinical trial, 240 Chinese children aged 6-13 years, spherical equivalent refractive error (SE) -0.75 D to -5.00 D were randomised to one of three groups of 80 participants each to wear: SV spectacle lens (N = 80), CARE spectacles (7 mm central clear zone surrounded by treatment zone incorporating CARE with mean surface power of +4.6 D) and CARE S (9 mm central clear zone surrounded by treatment zone comprising CARE with mean surface power of +3.8 D). Cycloplegic SE and axial length (AL) were measured at 6-month intervals. Compared to baseline, changes in SE and AL were significantly different between the groups at both 6 and 12 months (p < 0.001, linear mixed model). Adjusting for site, group, parental myopia and age, at 12 months, the estimated change in SE and AL with 95% CI with SV was -0.65 D (CI: -0.56 to -0.74 D)/0.32 mm (CI: 0.29-0.36 mm). In comparison, the estimated change in SE/AL at 12 months with CARE was -0.35 D (-0.26 to -0.44 D)/0.19 mm (0.15-0.22 mm) and with CARE S was -0.36 D (-0.27 to -0.46 D)/0.21 mm (0.18-0.25 mm) at 12 months. Progression was slower with CARE and CARE S compared to SV (p < 0.05) but did not differ from each other (p = 0.793 and 0.336 for SE and AL, respectively). In children with myopia, after 12 months of lens wear, both CARE and CARE S spectacle lenses significantly slowed myopia progression compared to SV lenses.

Treatment of Acanthamoeba keratitis with high dose PHMB (0.08%) monotherapy in clinical practice: A case series.

Acanthamoeba keratitis (AK) is a rare sight-threatening infectious disease with no approved pharmacological treatments. Topical polihexanide 0.8 mg/ml (PHMB 0.08%) completed a pivotal clinical trial showing a medical cure rate of 84.9%. The purpose of this study is to evaluate the efficacy and safety of PHMB 0.08%, given as monotherapy, in clinical practice. consecutive cases of AK were included. Diagnosis was confirmed by in vivo confocal microscopy or PCR. Patients were treated with PHMB 0.08% as part of a name-based compassionate use program. Treatment delivery frequency and termination were as advised in the pivotal clinical trial. Medical cure was defined as clinical evidence of healed epithelium and absence of corneal inflammation lasting 3 months after discontinuing all treatments. twelve eyes of 11 contact lens wearers with AK of variable severity were evaluated. Eleven of 12 (91.7%) eyes achieved a medical cure with no surgery. One eye had a corneal perforation and required emergency therapeutic keratoplasty. The median time of treatment with PHMB 0.08% was 100 days (range 35-222). Seven eyes (58.3%) reached a final visual acuity of 20/50 Snellen or better. Two subject reported worsening of conjunctival hyperaemia during the intensive phase of the treatment. No other adverse drug reactions were observed. topical treatment with PHMB 0.08% monotherapy successfully cured AK in 11 of 12 eyes when used in real-world clinical practice, thereby confirming that results observed in the clinical trial could be obtained in this setting.

Corneal asymmetry contributes decentration in both sphericaland toric orthokeratology lenses.

To discuss the characteristics of anterior corneal elevation asymmetry in myopic eyes and clarify which kind of asymmetry most influenced lens position. In this retrospective study of 199 consecutive myopic participants, corneal topography was used to analyse asymmetry in anterior corneal elevation. Amongst them, 65 participants (65 eyes) who underwent orthokeratology (31 and 34 with spherical and toric lenses, respectively) were re-evaluated. Stepwise multiple linear regression analysis was used to identify the contributing factors that influenced lens decentration. Receiver operating characteristic curve (ROC) analysis was employed to assess how the corneal asymmetry vector could predict decentration. There were no significant differences in treatment zone decentration (TZDec) between participants wearing toric and spherical lenses (p = 0.60 and 0.64 for 1 week and 1 month of wear, respectively). Amongst the underlying factors, the magnitude of TZDec was only correlated with the amount of corneal asymmetry vector (standardised β = 0.44, 0.48, p < 0.001 for all) after 1 week and 1 month of wear, and the direction of TZDec after 1 month of lens wear was associated with the angle of the asymmetry vector (r = 0.25, p = 0.04). ROC analysis showed that the magnitude of corneal asymmetry vector produced accurate discrimination between non-severe and severe decentration for 1 week and 1 month of wear (area under the curve was 0.93 ± 0.04 and 0.89 ± 0.05, respectively, p < 0.001). Amongst participants whose corneal asymmetry vector exceeded 41.06 μm and was oriented inferiorly, 35.29% showed severe decentration after 1 month of lens wear. In myopic participants, corneal asymmetry existed in the 8.0 mm chord diameter. If the asymmetry vector >41.06 μm and the direction was oriented inferiorly, then practitioners must be vigilant about severe decentration which would not be alleviated by a toric design.

Influence of Lifestyle Factors on Ocular Surface Parameters in Relation to Age.

To evaluate how Video Display Terminal (VDT) use, Contact Lens (CL) wear, and eyedrop use affect ocular surface parameters in participants with ocular discomfort and how these factors may vary across different age groups. The current cross-sectional study initially involved a total of 252 participants who completed a self-administered survey to collect information about ocular discomfort and lifestyle factors. This online survey was composed of an Ocular Surface Disease Index (OSDI) questionnaire and three extra questions regarding lifestyle factors (VDT use, CL wear, and eyedrop use). Only 185 symptomatic participants, those with OSDI values > 12, were scheduled to undergo a comprehensive ocular examination that included tear film osmolarity, Fluorescein Break-Up Time (FBUT), Maximum Blink Interval (MBI), and corneal staining. Differences in ocular parameters and lifestyle factors across age groups (<40 years, 40-60 years, >60 years) were analyzed, along with their correlations and regression. Significant age group differences were found in OSDI, osmolarity, FBUT, and MBI (One-way ANOVA, all p ≤ 0.029). Correlations were observed between CL wear and osmolarity and MBI (Pearson's correlation, both p ≤ 0.049). Multiple regression confirmed age associations with OSDI, osmolarity, FBUT, and MBI (Multiple linear regression, all p ≤ 0.040) and found links between VDT use and osmolarity and MBI (Multiple linear regression, both p ≤ 0.038) and between eyedrop use and OSDI (Multiple linear regression, p = 0.040). Aging is a primary factor affecting ocular homeostasis, with older adults showing lower FBUT and MBI values and higher osmolarity. Prolonged use of VDTs exacerbates this effect, further contributing to ocular discomfort and destabilized tear film. No associations between CL wear and any of the ocular parameters were found. Eyedrop use shows varied effects on ocular comfort across age groups, emphasizing the need for age-specific ocular care. Overall, these findings confirm that aging and extended VDT use play a significant role in ocular surface discomfort.

Clinical Outcomes of Infectious Keratitis Associated with Contact Lens Wear Following Penetrating Keratoplasty: A Case Series.

To report on the clinical characteristics, and outcomes of patients who developed infectious keratitis associated with contact lens (CL) wear following penetrating keratoplasty (PK). A retrospective chart review was performed to identify all patients who underwent PK between November 2012 and January 2023 at a single tertiary referral practice, and subsequently developed CL related infectious keratitis. 74 patients using CL following PK were identified. Charts were reviewed to obtain data about demographics, ocular history, CL usage, microbial culture reports, visual acuity, treatment, and clinical outcomes. CL-associated infectious keratitis occurred in 9 patients, more frequently in males (66%), and patients had a mean age of 54.5 ± 11.8years old. The identified causative organisms included: Stenotrophomonas maltophilia (N = 3), Candida parapsilosis (N = 2), Moraxella nonliquefaciens (N = 1), Pseudomonas aeruginosa (N = 1), Staphylococcus epidermidis (N = 1), Streptococcus mitis (N = 1), Candida albicans (N = 1), and Acanthamoeba (N = 1). Contact lenses were used following PK for an average of 9.1 ± 10.8months before development of keratitis. Patients were followed for 31.8 ± 30.2months after infection. The mean best corrected visual acuity without CL prior to infection was 20/150 and decreased to 20/260 post-infection. Complications following the contact-lens-associated infectious keratitis included: central corneal haze (N = 8), chronic corneal epithelial defects (N = 3), perforation (N = 3), endophthalmitis (N = 1), and enucleation (N = 1). Three grafts required repeat PK. CL-associated infectious keratitis following PK have high rates of complication. Patients should be monitored closely for signs of infection.

Evaluation of meibomian gland morphology in keratoconus patients wearing scleral contact lenses.

We aimed to evaluate the morphological changes in meibomian glands in keratoconus patients using scleral contact lenses and compare them with keratoconus and healthy controls. The study included 34 eyes of 20 patients who were wearing scleral contact lenses due to keratoconus, as well as 31 age- and sex-matched keratoconus controls and 31 healthy controls. Slit-lamp biomicroscopy, non-invasive tear film break-up time assessment, Schirmer I test, meibography, and corneal staining with fluorescein were performed. Subjective symptoms were assessed using the Ocular Surface Disease Index. In this study, the lower and upper percentage meibomian gland loss was statistically higher in the scleral contact lens group than in the keratoconus and healthy control groups (p < 0.001 and p = 0.013, respectively). There was a positive correlation between scleral contact lens wear duration and the lower eyelid percentage meibomian gland loss and upper eyelid gland curling scores (rho: 0.396; p = 0.021 and rho: 0.344; p = 0.047, respectively). The lower and upper eyelid percentage meibomian gland loss, and upper eyelid gland curling values were higher, and the Schirmer 1 values were found to be lower in patients who used scleral contact lenses for more than three years than those who wore them less than three years. In patients using scleral contact lenses for more than three years, meibomian gland curling values and percentages of meibomian gland loss in both eyelids are higher.

Microbial keratitis in north-western Spain: a review of risk factors, microbiological profile and resistance patterns.

To review the risk factors, clinical characteristics, and microbiological profiles of microbial keratitis cases, as well as the antibiotic resistance patterns of bacterial isolates in the region of Galicia, Spain. This retrospective case series includes patients with culture-positive non-viral microbial keratitis between 2010 and 2020, treated at nine hospitals within the region of Galicia, North-West Spain. The standard protocol involved Gram staining for bacterial infections and calcofluor white staining for fungal or amoebal infections, identification by MALDI-TOF mass spectrometry or microscopy, and antimicrobial susceptibility interpreted according to EUCAST or CLSI guidelines. 780 microorganisms were isolated from corneal scraping cultures from 654 patients. 36.9% resided in urban areas, and 63.1% in rural areas. Isolates were more frequently collected in spring and summer. The median time to corneal scraping was 0 days (IQR 0-2), and the median time to epithelialisation was 24.0 days (IQR 11-49). Most cases had a single corneal infiltrate (509 cases; 77.8%) and affected the stroma (432; 66.1%), with small (< 3mm) epithelial defects (347; 53.1%). Significant risk factors included contact lens wear (24.2%) and exposure to organic matter (4.9%). The most frequent bacteria was CoNS (207; 26.4). Fungi (77; 9.9%) and amoebae (6; 0.8%) were less common. Steroid use and eyelid disease increased resistance in CoNS species. An increase in the percentage of MRSA (compared to MSSA) was detected over the study period (p = 0.045). In Galicia (Spain), microbial keratitis was mostly attributed to CoNS. An increase in MRSA keratitis was observed. Analysis of risk factors may help in suspecting antibiotic resistance. Surveillance programs for detecting the development of antimicrobial resistance are necessary to provide treatment guidelines based on local data.

How Can We Better Inform Patients of the Importance of Contact Lens Compliance?: Current Perspectives.

Compliance with contact lens care is important for successful contact lens wear and for minimizing the risk of complications related to lens wear. There are many components of overall lens care guidelines that may potentially be disregarded, forgotten, or misunderstood. Literature has reported copious data on rates of poor compliance for separate lens care recommendations. Knowing the areas of contact lens care where lens wearers perform poorly is helpful when creating strategies for improving patient education. As science evolves and new best-practices are determined, eye care providers must be engaged in educating new lens wearers and reeducating existing wearers. It is vital to make wearers mindful of proper lens care and why proper lens care should be important to them. Various educational strategies can help practitioners to communicate with their patients more effectively. The purpose of this narrative review is to discuss studies of noncompliance with contact lens wear; consequences of these noncompliant behaviors; and studies of lens care education which were found with a literature search. The resulting discussion also includes strategies to improve compliance with patient contact lens wear.

Subjective Wearing Experience of Lehfilcon A Among Satisfied Comfilcon A Toric Lens Wearers.

To evaluate the subjective wearing experience of lehfilcon A toric lenses among subjects who were already satisfied with their comfilcon A toric lenses. This was an open-label, single arm study of currently satisfied comfilcon A soft toric contact lens (Biofinity Toric, CooperVision, Pleasanton, CA) wearers that were refit with lehfilcon A soft toric lenses (Total30® for Astigmatism; Alcon Vision LLC, Fort Worth, TX). Subjects were administered a questionnaire about satisfaction with comfort, visual performance, end of day comfort, and ease of handling with lehfilcon A toric lenses. A total of 40 subjects completed the study. After one month of wear the median and interquartile range (IQR) was 8 (2) for overall satisfaction with lehfilcon A comfort, 8 (1.25) for visual performance, 7 (3.25) for end of day comfort, 9 (2) for ease of handling, and finally 8 (2) for overall satisfaction. A high proportion of subjects were satisfied with the subjective wearing experience with lehfilcon A toric lenses, including satisfaction with comfort, visual performance, end of day comfort, and ease of handling.

Effect of text messages designed to change contact lens compliance: A randomised controlled trial

PurposeContact 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. MethodsThe 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. ResultsParticipants 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 %). ConclusionThis customised text message intervention was a feasible and acceptable method for improving contact lens compliance.

Comparison of trial lens-fitting and software-fitting in orthokeratology for myopia control in children with high corneal eccentric value

PurposeTo compare the safety and efficacy of the trial lens-fitting and software-fitting in orthokeratology for myopia control in children with high corneal eccentric value. MethodsMyopic children with high corneal eccentric value (≥0.65) receiving treatment for orthokeratology from July 2020 to January 2022 were included in this retrospective study. Only the right eyes were included. The participants were allocated into two groups: the trial lens-fitting group (n = 41) and the software-fitting group (n = 48). The uncorrected visual acuity (UCVA), corneal topography, and ocular health (Efron grading scales) were recorded at baseline, one week, two weeks, one, three, six, and 12 months afterthe initiation of lens wear. The axial length and endothelial cell density were assessed at baseline and after 12 months of lens wear. ResultsThe success rate of the first fit in the software-fitting group and trial lens-fitting group reached 98 % and 95 %, respectively. The difference in UCVA and corneal staining were statistically insignificant between the two groups during all visits. The software-fitting group exhibited a smaller treatment zone size (radius 1.69 ± 0.21 mm vs 1.81 ± 0.16 mm, p = 0.004; area 9.13 ± 2.15 mm2 vs 10.36 ± 1.82 mm2, p = 0.005) and less decentration (0.58 ± 0.31 mm vs 0.74 ± 0.39 mm, p = 0.036) compared with the trial lens-fitting group. There were no significant differences in axial elongation (0.15 ± 0.12 mm vs. 0.17 ± 0.14 mm, p = 0.534) or changes in endothelial cell density (−36.63 ± 99.37/mm2 vs − 13.71 ± 87.72/mm2, p = 0.256) between the software-fitting group and the trial lens-fitting group at one-year follow-up visit. ConclusionBoth fitting methods were effective and safe. However, the software-fitting method resulted in a smaller treatment zone size and less decentration.

Candida parapsilosis keratitis: A case series

Purposeto describe the diagnosis and management of Candida parapsilosis keratitis Designa retrospective, observational case series. Methodsthis study was carried out in a single-centre tertiary referral eye hospital and includes 20 eyes of 19 patients. Electronic case notes and in vivo confocal microscopy (IVCM) records were searched for the keyword ‘parapsilosis’, with inclusion if there was keratitis with either a corresponding positive polymerase chain reaction (PCR) or microbial culture result for Candida parapsilosis. Individual case notes were reviewed to obtain information regarding diagnosis, treatment, and final visual outcomes. Cases were excluded if a patient was lost to follow-up before the end of antifungal treatment. Resultsthe risk factors for C. parapsilosis keratitis were: ocular surface disease, concurrent topical steroid use, previous corneal surgery and long-term contact lens wear. The mean presenting corrected distance visual acuity (CDVA) was LogMAR 1.49 (range 0.2 – 2.3), with a final CDVA of LogMAR 1.11 (-0.2 – 2.3). Where used, microbiological culture was positive in 19 out of 20 cases, PCR in 6 out of 11 cases, and IVCM in 8 out of 13 cases. Two-thirds of cases were managed with either topical voriconazole or amphotericin B, with four cases surgically managed by therapeutic keratoplasty and two cases requiring evisceration. ConclusionsPatients presenting with microbial keratitis with risk factors for C. parapsilosis keratitis should be managed with a high degree of clinical suspicion. Post-infection visual outcomes are poor but reflect pre-existing ocular comorbidities. Delays in diagnosis can be reduced by through the use of ICVM and PCR.

The impact of extended contact lens wear on corneal health

The impact of extended contact lens wear on corneal health

Raman spectroscopy to investigate early biochemical alterations in human tears caused by contact lenses

ABSTRACT Clinical relevance The interaction between contact lenses and tear film plays a critical role in lens biocompatibility and can influence discomfort during wear. Early detection of biochemical changes is important for improving ocular surface health, preventing complications, and developing advanced lens materials to enhance long-term comfort. Background The pursuit of biocompatible lens materials requires a thorough understanding of their interaction with tear environment. The aim of this study is to evaluate different approaches to investigate early alterations in tear biomolecular profiles induced by lens wear. Methods Two participants wore different CLs and underwent ocular analysis before CL insertion (T0), after 2-hour wear (T2), and two hours after removing the CL (T4), evaluating non-invasive tear break-up time (NIBUT), tear meniscus height (TMH), and osmolarity. Forty CLs were used. At the same time points, tears were collected and analysed by Raman spectroscopy. Results Tear film stability, as measured by NIBUT, decreased post-lens wear (T0 vs T2, p = 0.034 and 0.025 for S1 and S2, respectively) but showed recovery within 2 hours (T0 vs T4, p > 0.05 for both S1 and S2), while TMH and osmolarity remained unchanged (T0 vs T2 vs T4, p > 0.05 for both S1 and S2). Raman spectroscopy highlighted notable changes in the biomolecular profile of tears after lens wear, particularly in the 2700–3200 cm−1 spectral window related to C-H stretching, which is sensitive to CH, CH2 and CH3 groups, their functional chemistry group, and the surrounding microenvironment. Conclusions Contact lens wear induces subtle biochemical, subclinical alterations in tears that can be detected early by Raman spectroscopy. The method is promising for analysing the subject-specific responses to lenses, also with possible individual variability in the timing of these changes. In addition, this approach can provide insights for designing biocompatible materials and for the early detection of subclinical biomarkers.

Orthokeratology for high myopia

Purpose. With an increasing proportion of children with myopia especially in Asia, efforts have been made to reduce chances of preventable sight loss related to high myopia in the future. Orthokeratology lens has been used as one of the modalities not just to correct myopia, but also to slow down myopic progression and axial elongation. This case report reviews a patient with clinically significantly high myopia, whose refractive errors was partially corrected with orthokeratology lens and spectacle lenses. Material and Methods. A now 14-year-old patient with a history of fast progressing myopia, was prescribed and commended orthokeratology to manage myopia, while regularly monitoring her refractive errors, axial length, binocular vision status, corneal topography, and anterior eye health was monitored regularly at the author’s practice. Results. Over a two year follow up period, a partial correction of high myopia with orthokeratology lenses and residual refractive errors with additional spectacle lenses was effective in managing this patient’s myopia, as well as slowing of axial elongation. An updated pair of orthokeratology lens with a steeper back optic zone radii were prescribed to reduce superficial corneal staining and to maintain corneal health. Conclusion. Patient commitment and adherence to close monitoring of eyes in terms refractive errors, axial length, and anterior eye health, are vital in achieving a successful orthokeratology lens wear for high myopia. A dual fitting strategy consisting of orthokeratology lens and spectacle wear can be a safe management strategy that is acceptable for patients with high myopia. It would be helpful for practitioners to be able to rely on robust evidence-based guidance when determining whether lens wear can be ceased, i.e. when further axial elongation and myopic progression are no longer likely.

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.